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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
//! A picture represents a dynamically rendered image.
//!
//! # Overview
//!
//! Pictures consists of:
//!
//! - A number of primitives that are drawn onto the picture.
//! - A composite operation describing how to composite this
//! picture into its parent.
//! - A configuration describing how to draw the primitives on
//! this picture (e.g. in screen space or local space).
//!
//! The tree of pictures are generated during scene building.
//!
//! Depending on their composite operations pictures can be rendered into
//! intermediate targets or folded into their parent picture.
//!
//! ## Picture caching
//!
//! Pictures can be cached to reduce the amount of rasterization happening per
//! frame.
//!
//! When picture caching is enabled, the scene is cut into a small number of slices,
//! typically:
//!
//! - content slice
//! - UI slice
//! - background UI slice which is hidden by the other two slices most of the time.
//!
//! Each of these slice is made up of fixed-size large tiles of 2048x512 pixels
//! (or 128x128 for the UI slice).
//!
//! Tiles can be either cached rasterized content into a texture or "clear tiles"
//! that contain only a solid color rectangle rendered directly during the composite
//! pass.
//!
//! ## Invalidation
//!
//! Each tile keeps track of the elements that affect it, which can be:
//!
//! - primitives
//! - clips
//! - image keys
//! - opacity bindings
//! - transforms
//!
//! These dependency lists are built each frame and compared to the previous frame to
//! see if the tile changed.
//!
//! The tile's primitive dependency information is organized in a quadtree, each node
//! storing an index buffer of tile primitive dependencies.
//!
//! The union of the invalidated leaves of each quadtree produces a per-tile dirty rect
//! which defines the scissor rect used when replaying the tile's drawing commands and
//! can be used for partial present.
//!
//! ## Display List shape
//!
//! WR will first look for an iframe item in the root stacking context to apply
//! picture caching to. If that's not found, it will apply to the entire root
//! stacking context of the display list. Apart from that, the format of the
//! display list is not important to picture caching. Each time a new scroll root
//! is encountered, a new picture cache slice will be created. If the display
//! list contains more than some arbitrary number of slices (currently 8), the
//! content will all be squashed into a single slice, in order to save GPU memory
//! and compositing performance.
//!
//! ## Compositor Surfaces
//!
//! Sometimes, a primitive would prefer to exist as a native compositor surface.
//! This allows a large and/or regularly changing primitive (such as a video, or
//! webgl canvas) to be updated each frame without invalidating the content of
//! tiles, and can provide a significant performance win and battery saving.
//!
//! Since drawing a primitive as a compositor surface alters the ordering of
//! primitives in a tile, we use 'overlay tiles' to ensure correctness. If a
//! tile has a compositor surface, _and_ that tile has primitives that overlap
//! the compositor surface rect, the tile switches to be drawn in alpha mode.
//!
//! We rely on only promoting compositor surfaces that are opaque primitives.
//! With this assumption, the tile(s) that intersect the compositor surface get
//! a 'cutout' in the rectangle where the compositor surface exists (not the
//! entire tile), allowing that tile to be drawn as an alpha tile after the
//! compositor surface.
//!
//! Tiles are only drawn in overlay mode if there is content that exists on top
//! of the compositor surface. Otherwise, we can draw the tiles in the normal fast
//! path before the compositor surface is drawn. Use of the per-tile valid and
//! dirty rects ensure that we do a minimal amount of per-pixel work here to
//! blend the overlay tile (this is not always optimal right now, but will be
//! improved as a follow up).
use api::{MixBlendMode, PremultipliedColorF, FilterPrimitiveKind};
use api::{PropertyBinding, PropertyBindingId, FilterPrimitive, RasterSpace};
use api::{DebugFlags, ImageKey, ColorF, ColorU, PrimitiveFlags};
use api::{ImageRendering, ColorDepth, YuvRangedColorSpace, YuvFormat, AlphaType};
use api::units::*;
use crate::command_buffer::PrimitiveCommand;
use crate::box_shadow::BLUR_SAMPLE_SCALE;
use crate::clip::{ClipStore, ClipChainInstance, ClipLeafId, ClipNodeId, ClipTreeBuilder};
use crate::spatial_tree::{SpatialTree, CoordinateSpaceMapping, SpatialNodeIndex, VisibleFace};
use crate::composite::{CompositorKind, CompositeState, NativeSurfaceId, NativeTileId, CompositeTileSurface, tile_kind};
use crate::composite::{ExternalSurfaceDescriptor, ExternalSurfaceDependency, CompositeTileDescriptor, CompositeTile};
use crate::composite::{CompositorTransformIndex, CompositorSurfaceKind};
use crate::debug_colors;
use euclid::{vec3, Point2D, Scale, Vector2D, Box2D};
use euclid::approxeq::ApproxEq;
use crate::filterdata::SFilterData;
use crate::intern::ItemUid;
use crate::internal_types::{FastHashMap, FastHashSet, PlaneSplitter, Filter, FrameId};
use crate::internal_types::{PlaneSplitterIndex, PlaneSplitAnchor, TextureSource};
use crate::frame_builder::{FrameBuildingContext, FrameBuildingState, PictureState, PictureContext};
use crate::gpu_cache::{GpuCache, GpuCacheAddress, GpuCacheHandle};
use crate::gpu_types::{UvRectKind, ZBufferId};
use peek_poke::{PeekPoke, poke_into_vec, peek_from_slice, ensure_red_zone};
use plane_split::{Clipper, Polygon};
use crate::prim_store::{PrimitiveTemplateKind, PictureIndex, PrimitiveInstance, PrimitiveInstanceKind};
use crate::prim_store::{ColorBindingStorage, ColorBindingIndex, PrimitiveScratchBuffer};
use crate::print_tree::{PrintTree, PrintTreePrinter};
use crate::render_backend::DataStores;
use crate::render_task_graph::RenderTaskId;
use crate::render_target::RenderTargetKind;
use crate::render_task::{BlurTask, RenderTask, RenderTaskLocation, BlurTaskCache};
use crate::render_task::{StaticRenderTaskSurface, RenderTaskKind};
use crate::renderer::BlendMode;
use crate::resource_cache::{ResourceCache, ImageGeneration, ImageRequest};
use crate::space::SpaceMapper;
use crate::scene::SceneProperties;
use crate::spatial_tree::CoordinateSystemId;
use crate::surface::{SurfaceDescriptor, SurfaceTileDescriptor};
use smallvec::SmallVec;
use std::{mem, u8, marker, u32};
use std::sync::atomic::{AtomicUsize, Ordering};
use std::collections::hash_map::Entry;
use std::ops::Range;
use crate::picture_textures::PictureCacheTextureHandle;
use crate::util::{MaxRect, VecHelper, MatrixHelpers, Recycler, ScaleOffset};
use crate::filterdata::FilterDataHandle;
use crate::tile_cache::{SliceDebugInfo, TileDebugInfo, DirtyTileDebugInfo};
use crate::visibility::{PrimitiveVisibilityFlags, FrameVisibilityContext};
use crate::visibility::{VisibilityState, FrameVisibilityState};
use crate::scene_building::SliceFlags;
// Maximum blur radius for blur filter (different than box-shadow blur).
// Taken from FilterNodeSoftware.cpp in Gecko.
const MAX_BLUR_RADIUS: f32 = 100.;
/// Specify whether a surface allows subpixel AA text rendering.
#[derive(Debug, Copy, Clone)]
pub enum SubpixelMode {
/// This surface allows subpixel AA text
Allow,
/// Subpixel AA text cannot be drawn on this surface
Deny,
/// Subpixel AA can be drawn on this surface, if not intersecting
/// with the excluded regions, and inside the allowed rect.
Conditional {
allowed_rect: PictureRect,
prohibited_rect: PictureRect,
},
}
/// A comparable transform matrix, that compares with epsilon checks.
#[derive(Debug, Clone)]
struct MatrixKey {
m: [f32; 16],
}
impl PartialEq for MatrixKey {
fn eq(&self, other: &Self) -> bool {
const EPSILON: f32 = 0.001;
// TODO(gw): It's possible that we may need to adjust the epsilon
// to be tighter on most of the matrix, except the
// translation parts?
for (i, j) in self.m.iter().zip(other.m.iter()) {
if !i.approx_eq_eps(j, &EPSILON) {
return false;
}
}
true
}
}
/// A comparable scale-offset, that compares with epsilon checks.
#[derive(Debug, Clone)]
struct ScaleOffsetKey {
sx: f32,
sy: f32,
tx: f32,
ty: f32,
}
impl PartialEq for ScaleOffsetKey {
fn eq(&self, other: &Self) -> bool {
const EPSILON: f32 = 0.001;
self.sx.approx_eq_eps(&other.sx, &EPSILON) &&
self.sy.approx_eq_eps(&other.sy, &EPSILON) &&
self.tx.approx_eq_eps(&other.tx, &EPSILON) &&
self.ty.approx_eq_eps(&other.ty, &EPSILON)
}
}
/// A comparable / hashable version of a coordinate space mapping. Used to determine
/// if a transform dependency for a tile has changed.
#[derive(Debug, PartialEq, Clone)]
enum TransformKey {
Local,
ScaleOffset {
so: ScaleOffsetKey,
},
Transform {
m: MatrixKey,
}
}
impl<Src, Dst> From<CoordinateSpaceMapping<Src, Dst>> for TransformKey {
fn from(transform: CoordinateSpaceMapping<Src, Dst>) -> TransformKey {
match transform {
CoordinateSpaceMapping::Local => {
TransformKey::Local
}
CoordinateSpaceMapping::ScaleOffset(ref scale_offset) => {
TransformKey::ScaleOffset {
so: ScaleOffsetKey {
sx: scale_offset.scale.x,
sy: scale_offset.scale.y,
tx: scale_offset.offset.x,
ty: scale_offset.offset.y,
}
}
}
CoordinateSpaceMapping::Transform(ref m) => {
TransformKey::Transform {
m: MatrixKey {
m: m.to_array(),
},
}
}
}
}
}
/// Unit for tile coordinates.
#[derive(Hash, Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd)]
pub struct TileCoordinate;
// Geometry types for tile coordinates.
pub type TileOffset = Point2D<i32, TileCoordinate>;
pub type TileRect = Box2D<i32, TileCoordinate>;
/// The maximum number of compositor surfaces that are allowed per picture cache. This
/// is an arbitrary number that should be enough for common cases, but low enough to
/// prevent performance and memory usage drastically degrading in pathological cases.
pub const MAX_COMPOSITOR_SURFACES: usize = 4;
/// The size in device pixels of a normal cached tile.
pub const TILE_SIZE_DEFAULT: DeviceIntSize = DeviceIntSize {
width: 1024,
height: 512,
_unit: marker::PhantomData,
};
/// The size in device pixels of a tile for horizontal scroll bars
pub const TILE_SIZE_SCROLLBAR_HORIZONTAL: DeviceIntSize = DeviceIntSize {
width: 1024,
height: 32,
_unit: marker::PhantomData,
};
/// The size in device pixels of a tile for vertical scroll bars
pub const TILE_SIZE_SCROLLBAR_VERTICAL: DeviceIntSize = DeviceIntSize {
width: 32,
height: 1024,
_unit: marker::PhantomData,
};
/// The maximum size per axis of a surface,
/// in WorldPixel coordinates.
const MAX_SURFACE_SIZE: usize = 4096;
/// Maximum size of a compositor surface.
const MAX_COMPOSITOR_SURFACES_SIZE: f32 = 8192.0;
/// Used to get unique tile IDs, even when the tile cache is
/// destroyed between display lists / scenes.
static NEXT_TILE_ID: AtomicUsize = AtomicUsize::new(0);
fn clamp(value: i32, low: i32, high: i32) -> i32 {
value.max(low).min(high)
}
fn clampf(value: f32, low: f32, high: f32) -> f32 {
value.max(low).min(high)
}
/// An index into the prims array in a TileDescriptor.
#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct PrimitiveDependencyIndex(pub u32);
/// Information about the state of a binding.
#[derive(Debug)]
pub struct BindingInfo<T> {
/// The current value retrieved from dynamic scene properties.
value: T,
/// True if it was changed (or is new) since the last frame build.
changed: bool,
}
/// Information stored in a tile descriptor for a binding.
#[derive(Debug, PartialEq, Clone, Copy, PeekPoke)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub enum Binding<T> {
Value(T),
Binding(PropertyBindingId),
}
impl<T: Default> Default for Binding<T> {
fn default() -> Self {
Binding::Value(T::default())
}
}
impl<T> From<PropertyBinding<T>> for Binding<T> {
fn from(binding: PropertyBinding<T>) -> Binding<T> {
match binding {
PropertyBinding::Binding(key, _) => Binding::Binding(key.id),
PropertyBinding::Value(value) => Binding::Value(value),
}
}
}
pub type OpacityBinding = Binding<f32>;
pub type OpacityBindingInfo = BindingInfo<f32>;
pub type ColorBinding = Binding<ColorU>;
pub type ColorBindingInfo = BindingInfo<ColorU>;
#[derive(PeekPoke)]
enum PrimitiveDependency {
OpacityBinding {
binding: OpacityBinding,
},
ColorBinding {
binding: ColorBinding,
},
SpatialNode {
index: SpatialNodeIndex,
},
Clip {
clip: ItemUid,
},
Image {
image: ImageDependency,
},
}
/// A dependency for a transform is defined by the spatial node index + frame it was used
#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash, PeekPoke, Default)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct SpatialNodeKey {
spatial_node_index: SpatialNodeIndex,
frame_id: FrameId,
}
/// A helper for comparing spatial nodes between frames. The comparisons
/// are done by-value, so that if the shape of the spatial node tree
/// changes, invalidations aren't done simply due to the spatial node
/// index changing between display lists.
struct SpatialNodeComparer {
/// The root spatial node index of the tile cache
ref_spatial_node_index: SpatialNodeIndex,
/// Maintains a map of currently active transform keys
spatial_nodes: FastHashMap<SpatialNodeKey, TransformKey>,
/// A cache of recent comparisons between prev and current spatial nodes
compare_cache: FastHashMap<(SpatialNodeKey, SpatialNodeKey), bool>,
/// A set of frames that we need to retain spatial node entries for
referenced_frames: FastHashSet<FrameId>,
}
impl SpatialNodeComparer {
/// Construct a new comparer
fn new() -> Self {
SpatialNodeComparer {
ref_spatial_node_index: SpatialNodeIndex::INVALID,
spatial_nodes: FastHashMap::default(),
compare_cache: FastHashMap::default(),
referenced_frames: FastHashSet::default(),
}
}
/// Advance to the next frame
fn next_frame(
&mut self,
ref_spatial_node_index: SpatialNodeIndex,
) {
// Drop any node information for unreferenced frames, to ensure that the
// hashmap doesn't grow indefinitely!
let referenced_frames = &self.referenced_frames;
self.spatial_nodes.retain(|key, _| {
referenced_frames.contains(&key.frame_id)
});
// Update the root spatial node for this comparer
self.ref_spatial_node_index = ref_spatial_node_index;
self.compare_cache.clear();
self.referenced_frames.clear();
}
/// Register a transform that is used, and build the transform key for it if new.
fn register_used_transform(
&mut self,
spatial_node_index: SpatialNodeIndex,
frame_id: FrameId,
spatial_tree: &SpatialTree,
) {
let key = SpatialNodeKey {
spatial_node_index,
frame_id,
};
if let Entry::Vacant(entry) = self.spatial_nodes.entry(key) {
entry.insert(
get_transform_key(
spatial_node_index,
self.ref_spatial_node_index,
spatial_tree,
)
);
}
}
/// Return true if the transforms for two given spatial nodes are considered equivalent
fn are_transforms_equivalent(
&mut self,
prev_spatial_node_key: &SpatialNodeKey,
curr_spatial_node_key: &SpatialNodeKey,
) -> bool {
let key = (*prev_spatial_node_key, *curr_spatial_node_key);
let spatial_nodes = &self.spatial_nodes;
*self.compare_cache
.entry(key)
.or_insert_with(|| {
let prev = &spatial_nodes[&prev_spatial_node_key];
let curr = &spatial_nodes[&curr_spatial_node_key];
curr == prev
})
}
/// Ensure that the comparer won't GC any nodes for a given frame id
fn retain_for_frame(&mut self, frame_id: FrameId) {
self.referenced_frames.insert(frame_id);
}
}
// Immutable context passed to picture cache tiles during pre_update
struct TilePreUpdateContext {
/// Maps from picture cache coords -> world space coords.
pic_to_world_mapper: SpaceMapper<PicturePixel, WorldPixel>,
/// The optional background color of the picture cache instance
background_color: Option<ColorF>,
/// The visible part of the screen in world coords.
global_screen_world_rect: WorldRect,
/// Current size of tiles in picture units.
tile_size: PictureSize,
/// The current frame id for this picture cache
frame_id: FrameId,
}
// Immutable context passed to picture cache tiles during update_dirty_and_valid_rects
struct TileUpdateDirtyContext<'a> {
/// Maps from picture cache coords -> world space coords.
pic_to_world_mapper: SpaceMapper<PicturePixel, WorldPixel>,
/// Global scale factor from world -> device pixels.
global_device_pixel_scale: DevicePixelScale,
/// Information about opacity bindings from the picture cache.
opacity_bindings: &'a FastHashMap<PropertyBindingId, OpacityBindingInfo>,
/// Information about color bindings from the picture cache.
color_bindings: &'a FastHashMap<PropertyBindingId, ColorBindingInfo>,
/// The local rect of the overall picture cache
local_rect: PictureRect,
/// If true, the scale factor of the root transform for this picture
/// cache changed, so we need to invalidate the tile and re-render.
invalidate_all: bool,
}
// Mutable state passed to picture cache tiles during update_dirty_and_valid_rects
struct TileUpdateDirtyState<'a> {
/// Allow access to the texture cache for requesting tiles
resource_cache: &'a mut ResourceCache,
/// Current configuration and setup for compositing all the picture cache tiles in renderer.
composite_state: &'a mut CompositeState,
/// A cache of comparison results to avoid re-computation during invalidation.
compare_cache: &'a mut FastHashMap<PrimitiveComparisonKey, PrimitiveCompareResult>,
/// Information about transform node differences from last frame.
spatial_node_comparer: &'a mut SpatialNodeComparer,
}
// Immutable context passed to picture cache tiles during post_update
struct TilePostUpdateContext<'a> {
/// The local clip rect (in picture space) of the entire picture cache
local_clip_rect: PictureRect,
/// The calculated backdrop information for this cache instance.
backdrop: Option<BackdropInfo>,
/// Current size in device pixels of tiles for this cache
current_tile_size: DeviceIntSize,
/// Pre-allocated z-id to assign to tiles during post_update.
z_id: ZBufferId,
/// The list of compositor underlays for this picture cache
underlays: &'a [ExternalSurfaceDescriptor],
}
// Mutable state passed to picture cache tiles during post_update
struct TilePostUpdateState<'a> {
/// Allow access to the texture cache for requesting tiles
resource_cache: &'a mut ResourceCache,
/// Current configuration and setup for compositing all the picture cache tiles in renderer.
composite_state: &'a mut CompositeState,
}
/// Information about the dependencies of a single primitive instance.
struct PrimitiveDependencyInfo {
/// Unique content identifier of the primitive.
prim_uid: ItemUid,
/// The (conservative) clipped area in picture space this primitive occupies.
prim_clip_box: PictureBox2D,
/// Image keys this primitive depends on.
images: SmallVec<[ImageDependency; 8]>,
/// Opacity bindings this primitive depends on.
opacity_bindings: SmallVec<[OpacityBinding; 4]>,
/// Color binding this primitive depends on.
color_binding: Option<ColorBinding>,
/// Clips that this primitive depends on.
clips: SmallVec<[ItemUid; 8]>,
/// Spatial nodes references by the clip dependencies of this primitive.
spatial_nodes: SmallVec<[SpatialNodeIndex; 4]>,
}
impl PrimitiveDependencyInfo {
/// Construct dependency info for a new primitive.
fn new(
prim_uid: ItemUid,
prim_clip_box: PictureBox2D,
) -> Self {
PrimitiveDependencyInfo {
prim_uid,
images: SmallVec::new(),
opacity_bindings: SmallVec::new(),
color_binding: None,
prim_clip_box,
clips: SmallVec::new(),
spatial_nodes: SmallVec::new(),
}
}
}
/// A stable ID for a given tile, to help debugging. These are also used
/// as unique identifiers for tile surfaces when using a native compositor.
#[derive(Debug, Copy, Clone, PartialEq, PartialOrd, Ord, Eq)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct TileId(pub usize);
/// Uniquely identifies a tile within a picture cache slice
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
#[derive(Debug, Copy, Clone, PartialEq, Hash, Eq)]
pub struct TileKey {
// Tile index (x,y)
pub tile_offset: TileOffset,
// Sub-slice (z)
pub sub_slice_index: SubSliceIndex,
}
/// A descriptor for the kind of texture that a picture cache tile will
/// be drawn into.
#[derive(Debug)]
pub enum SurfaceTextureDescriptor {
/// When using the WR compositor, the tile is drawn into an entry
/// in the WR texture cache.
TextureCache {
handle: Option<PictureCacheTextureHandle>,
},
/// When using an OS compositor, the tile is drawn into a native
/// surface identified by arbitrary id.
Native {
/// The arbitrary id of this tile.
id: Option<NativeTileId>,
},
}
/// This is the same as a `SurfaceTextureDescriptor` but has been resolved
/// into a texture cache handle (if appropriate) that can be used by the
/// batching and compositing code in the renderer.
#[derive(Clone, Debug, Eq, PartialEq, Hash)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub enum ResolvedSurfaceTexture {
TextureCache {
/// The texture ID to draw to.
texture: TextureSource,
},
Native {
/// The arbitrary id of this tile.
id: NativeTileId,
/// The size of the tile in device pixels.
size: DeviceIntSize,
}
}
impl SurfaceTextureDescriptor {
/// Create a resolved surface texture for this descriptor
pub fn resolve(
&self,
resource_cache: &ResourceCache,
size: DeviceIntSize,
) -> ResolvedSurfaceTexture {
match self {
SurfaceTextureDescriptor::TextureCache { handle } => {
let texture = resource_cache
.picture_textures
.get_texture_source(handle.as_ref().unwrap());
ResolvedSurfaceTexture::TextureCache { texture }
}
SurfaceTextureDescriptor::Native { id } => {
ResolvedSurfaceTexture::Native {
id: id.expect("bug: native surface not allocated"),
size,
}
}
}
}
}
/// The backing surface for this tile.
#[derive(Debug)]
pub enum TileSurface {
Texture {
/// Descriptor for the surface that this tile draws into.
descriptor: SurfaceTextureDescriptor,
},
Color {
color: ColorF,
},
Clear,
}
impl TileSurface {
fn kind(&self) -> &'static str {
match *self {
TileSurface::Color { .. } => "Color",
TileSurface::Texture { .. } => "Texture",
TileSurface::Clear => "Clear",
}
}
}
/// Optional extra information returned by is_same when
/// logging is enabled.
#[derive(Debug, Copy, Clone, PartialEq)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub enum CompareHelperResult<T> {
/// Primitives match
Equal,
/// Counts differ
Count {
prev_count: u8,
curr_count: u8,
},
/// Sentinel
Sentinel,
/// Two items are not equal
NotEqual {
prev: T,
curr: T,
},
/// User callback returned true on item
PredicateTrue {
curr: T
},
}
/// The result of a primitive dependency comparison. Size is a u8
/// since this is a hot path in the code, and keeping the data small
/// is a performance win.
#[derive(Debug, Copy, Clone, PartialEq)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
#[repr(u8)]
pub enum PrimitiveCompareResult {
/// Primitives match
Equal,
/// Something in the PrimitiveDescriptor was different
Descriptor,
/// The clip node content or spatial node changed
Clip,
/// The value of the transform changed
Transform,
/// An image dependency was dirty
Image,
/// The value of an opacity binding changed
OpacityBinding,
/// The value of a color binding changed
ColorBinding,
}
/// Debugging information about why a tile was invalidated
#[derive(Debug,Clone)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub enum InvalidationReason {
/// The background color changed
BackgroundColor,
/// The opaque state of the backing native surface changed
SurfaceOpacityChanged,
/// There was no backing texture (evicted or never rendered)
NoTexture,
/// There was no backing native surface (never rendered, or recreated)
NoSurface,
/// The primitive count in the dependency list was different
PrimCount,
/// The content of one of the primitives was different
Content,
// The compositor type changed
CompositorKindChanged,
// The valid region of the tile changed
ValidRectChanged,
// The overall scale of the picture cache changed
ScaleChanged,
// The content of the sampling surface changed
SurfaceContentChanged,
}
/// Information about a cached tile.
pub struct Tile {
/// The grid position of this tile within the picture cache
pub tile_offset: TileOffset,
/// The current world rect of this tile.
pub world_tile_rect: WorldRect,
/// The current local rect of this tile.
pub local_tile_rect: PictureRect,
/// The picture space dirty rect for this tile.
pub local_dirty_rect: PictureRect,
/// The device space dirty rect for this tile.
/// TODO(gw): We have multiple dirty rects available due to the quadtree above. In future,
/// expose these as multiple dirty rects, which will help in some cases.
pub device_dirty_rect: DeviceRect,
/// World space rect that contains valid pixels region of this tile.
pub world_valid_rect: WorldRect,
/// Device space rect that contains valid pixels region of this tile.
pub device_valid_rect: DeviceRect,
/// Uniquely describes the content of this tile, in a way that can be
/// (reasonably) efficiently hashed and compared.
pub current_descriptor: TileDescriptor,
/// The content descriptor for this tile from the previous frame.
pub prev_descriptor: TileDescriptor,
/// Handle to the backing surface for this tile.
pub surface: Option<TileSurface>,
/// If true, this tile is marked valid, and the existing texture
/// cache handle can be used. Tiles are invalidated during the
/// build_dirty_regions method.
pub is_valid: bool,
/// If true, this tile intersects with the currently visible screen
/// rect, and will be drawn.
pub is_visible: bool,
/// The tile id is stable between display lists and / or frames,
/// if the tile is retained. Useful for debugging tile evictions.
pub id: TileId,
/// If true, the tile was determined to be opaque, which means blending
/// can be disabled when drawing it.
pub is_opaque: bool,
/// Root node of the quadtree dirty rect tracker.
root: TileNode,
/// The last rendered background color on this tile.
background_color: Option<ColorF>,
/// The first reason the tile was invalidated this frame.
invalidation_reason: Option<InvalidationReason>,
/// The local space valid rect for all primitives that affect this tile.
pub local_valid_rect: PictureBox2D,
/// z-buffer id for this tile
pub z_id: ZBufferId,
pub sub_graphs: Vec<(PictureRect, Vec<(PictureCompositeMode, SurfaceIndex)>)>,
}
impl Tile {
/// Construct a new, invalid tile.
fn new(tile_offset: TileOffset) -> Self {
let id = TileId(NEXT_TILE_ID.fetch_add(1, Ordering::Relaxed));
Tile {
tile_offset,
local_tile_rect: PictureRect::zero(),
world_tile_rect: WorldRect::zero(),
world_valid_rect: WorldRect::zero(),
device_valid_rect: DeviceRect::zero(),
local_dirty_rect: PictureRect::zero(),
device_dirty_rect: DeviceRect::zero(),
surface: None,
current_descriptor: TileDescriptor::new(),
prev_descriptor: TileDescriptor::new(),
is_valid: false,
is_visible: false,
id,
is_opaque: false,
root: TileNode::new_leaf(Vec::new()),
background_color: None,
invalidation_reason: None,
local_valid_rect: PictureBox2D::zero(),
z_id: ZBufferId::invalid(),
sub_graphs: Vec::new(),
}
}
/// Print debug information about this tile to a tree printer.
fn print(&self, pt: &mut dyn PrintTreePrinter) {
pt.new_level(format!("Tile {:?}", self.id));
pt.add_item(format!("local_tile_rect: {:?}", self.local_tile_rect));
pt.add_item(format!("background_color: {:?}", self.background_color));
pt.add_item(format!("invalidation_reason: {:?}", self.invalidation_reason));
self.current_descriptor.print(pt);
pt.end_level();
}
/// Check if the content of the previous and current tile descriptors match
fn update_dirty_rects(
&mut self,
ctx: &TileUpdateDirtyContext,
state: &mut TileUpdateDirtyState,
invalidation_reason: &mut Option<InvalidationReason>,
frame_context: &FrameVisibilityContext,
) -> PictureRect {
let mut prim_comparer = PrimitiveComparer::new(
&self.prev_descriptor,
&self.current_descriptor,
state.resource_cache,
state.spatial_node_comparer,
ctx.opacity_bindings,
ctx.color_bindings,
);
let mut dirty_rect = PictureBox2D::zero();
self.root.update_dirty_rects(
&self.prev_descriptor.prims,
&self.current_descriptor.prims,
&mut prim_comparer,
&mut dirty_rect,
state.compare_cache,
invalidation_reason,
frame_context,
);
dirty_rect
}
/// Invalidate a tile based on change in content. This
/// must be called even if the tile is not currently
/// visible on screen. We might be able to improve this
/// later by changing how ComparableVec is used.
fn update_content_validity(
&mut self,
ctx: &TileUpdateDirtyContext,
state: &mut TileUpdateDirtyState,
frame_context: &FrameVisibilityContext,
) {
// Check if the contents of the primitives, clips, and
// other dependencies are the same.
state.compare_cache.clear();
let mut invalidation_reason = None;
let dirty_rect = self.update_dirty_rects(
ctx,
state,
&mut invalidation_reason,
frame_context,
);
if !dirty_rect.is_empty() {
self.invalidate(
Some(dirty_rect),
invalidation_reason.expect("bug: no invalidation_reason"),
);
}
if ctx.invalidate_all {
self.invalidate(None, InvalidationReason::ScaleChanged);
}
// TODO(gw): We can avoid invalidating the whole tile in some cases here,
// but it should be a fairly rare invalidation case.
if self.current_descriptor.local_valid_rect != self.prev_descriptor.local_valid_rect {
self.invalidate(None, InvalidationReason::ValidRectChanged);
state.composite_state.dirty_rects_are_valid = false;
}
}
/// Invalidate this tile. If `invalidation_rect` is None, the entire
/// tile is invalidated.
fn invalidate(
&mut self,
invalidation_rect: Option<PictureRect>,
reason: InvalidationReason,
) {
self.is_valid = false;
match invalidation_rect {
Some(rect) => {
self.local_dirty_rect = self.local_dirty_rect.union(&rect);
}
None => {
self.local_dirty_rect = self.local_tile_rect;
}
}
if self.invalidation_reason.is_none() {
self.invalidation_reason = Some(reason);
}
}
/// Called during pre_update of a tile cache instance. Allows the
/// tile to setup state before primitive dependency calculations.
fn pre_update(
&mut self,
ctx: &TilePreUpdateContext,
) {
self.local_tile_rect = PictureRect::from_origin_and_size(
PicturePoint::new(
self.tile_offset.x as f32 * ctx.tile_size.width,
self.tile_offset.y as f32 * ctx.tile_size.height,
),
ctx.tile_size,
);
// TODO(gw): This is a hack / fix for Box2D::union in euclid not working with
// zero sized rect accumulation. Once that lands, we'll revert this
// to be zero.
self.local_valid_rect = PictureBox2D::new(
PicturePoint::new( 1.0e32, 1.0e32),
PicturePoint::new(-1.0e32, -1.0e32),
);
self.invalidation_reason = None;
self.sub_graphs.clear();
self.world_tile_rect = ctx.pic_to_world_mapper
.map(&self.local_tile_rect)
.expect("bug: map local tile rect");
// Check if this tile is currently on screen.
self.is_visible = self.world_tile_rect.intersects(&ctx.global_screen_world_rect);
// If the tile isn't visible, early exit, skipping the normal set up to
// validate dependencies. Instead, we will only compare the current tile
// dependencies the next time it comes into view.
if !self.is_visible {
return;
}
if ctx.background_color != self.background_color {
self.invalidate(None, InvalidationReason::BackgroundColor);
self.background_color = ctx.background_color;
}
// Clear any dependencies so that when we rebuild them we
// can compare if the tile has the same content.
mem::swap(
&mut self.current_descriptor,
&mut self.prev_descriptor,
);
self.current_descriptor.clear();
self.root.clear(self.local_tile_rect);
// Since this tile is determined to be visible, it will get updated
// dependencies, so update the frame id we are storing dependencies for.
self.current_descriptor.last_updated_frame_id = ctx.frame_id;
}
/// Add dependencies for a given primitive to this tile.
fn add_prim_dependency(
&mut self,
info: &PrimitiveDependencyInfo,
) {
// If this tile isn't currently visible, we don't want to update the dependencies
// for this tile, as an optimization, since it won't be drawn anyway.
if !self.is_visible {
return;
}
// Incorporate the bounding rect of the primitive in the local valid rect
// for this tile. This is used to minimize the size of the scissor rect
// during rasterization and the draw rect during composition of partial tiles.
self.local_valid_rect = self.local_valid_rect.union(&info.prim_clip_box);
// TODO(gw): The prim_clip_rect can be impacted by the clip rect of the display port,
// which can cause invalidations when a new display list with changed
// display port is received. To work around this, clamp the prim clip rect
// to the tile boundaries - if the clip hasn't affected the tile, then the
// changed clip can't affect the content of the primitive on this tile.
// In future, we could consider supplying the display port clip from Gecko
// in a different way (e.g. as a scroll frame clip) which still provides
// the desired clip for checkerboarding, but doesn't require this extra
// work below.
// TODO(gw): This is a hot part of the code - we could probably optimize further by:
// - Using min/max instead of clamps below (if we guarantee the rects are well formed)
let tile_p0 = self.local_tile_rect.min;
let tile_p1 = self.local_tile_rect.max;
let prim_clip_box = PictureBox2D::new(
PicturePoint::new(
clampf(info.prim_clip_box.min.x, tile_p0.x, tile_p1.x),
clampf(info.prim_clip_box.min.y, tile_p0.y, tile_p1.y),
),
PicturePoint::new(
clampf(info.prim_clip_box.max.x, tile_p0.x, tile_p1.x),
clampf(info.prim_clip_box.max.y, tile_p0.y, tile_p1.y),
),
);
// Update the tile descriptor, used for tile comparison during scene swaps.
let prim_index = PrimitiveDependencyIndex(self.current_descriptor.prims.len() as u32);
// Encode the deps for this primitive in the `dep_data` byte buffer
let dep_offset = self.current_descriptor.dep_data.len() as u32;
let mut dep_count = 0;
for clip in &info.clips {
dep_count += 1;
poke_into_vec(
&PrimitiveDependency::Clip {
clip: *clip,
},
&mut self.current_descriptor.dep_data,
);
}
for spatial_node_index in &info.spatial_nodes {
dep_count += 1;
poke_into_vec(
&PrimitiveDependency::SpatialNode {
index: *spatial_node_index,
},
&mut self.current_descriptor.dep_data,
);
}
for image in &info.images {
dep_count += 1;
poke_into_vec(
&PrimitiveDependency::Image {
image: *image,
},
&mut self.current_descriptor.dep_data,
);
}
for binding in &info.opacity_bindings {
dep_count += 1;
poke_into_vec(
&PrimitiveDependency::OpacityBinding {
binding: *binding,
},
&mut self.current_descriptor.dep_data,
);
}
if let Some(ref binding) = info.color_binding {
dep_count += 1;
poke_into_vec(
&PrimitiveDependency::ColorBinding {
binding: *binding,
},
&mut self.current_descriptor.dep_data,
);
}
self.current_descriptor.prims.push(PrimitiveDescriptor {
prim_uid: info.prim_uid,
prim_clip_box,
dep_offset,
dep_count,
});
// Add this primitive to the dirty rect quadtree.
self.root.add_prim(prim_index, &info.prim_clip_box);
}
/// Called during tile cache instance post_update. Allows invalidation and dirty
/// rect calculation after primitive dependencies have been updated.
fn update_dirty_and_valid_rects(
&mut self,
ctx: &TileUpdateDirtyContext,
state: &mut TileUpdateDirtyState,
frame_context: &FrameVisibilityContext,
) {
// Ensure peek-poke constraint is met, that `dep_data` is large enough
ensure_red_zone::<PrimitiveDependency>(&mut self.current_descriptor.dep_data);
// Register the frame id of this tile with the spatial node comparer, to ensure
// that it doesn't GC any spatial nodes from the comparer that are referenced
// by this tile. Must be done before we early exit below, so that we retain
// spatial node info even for tiles that are currently not visible.
state.spatial_node_comparer.retain_for_frame(self.current_descriptor.last_updated_frame_id);
// If tile is not visible, just early out from here - we don't update dependencies
// so don't want to invalidate, merge, split etc. The tile won't need to be drawn
// (and thus updated / invalidated) until it is on screen again.
if !self.is_visible {
return;
}
// Calculate the overall valid rect for this tile.
self.current_descriptor.local_valid_rect = self.local_valid_rect;
// TODO(gw): In theory, the local tile rect should always have an
// intersection with the overall picture rect. In practice,
// due to some accuracy issues with how fract_offset (and
// fp accuracy) are used in the calling method, this isn't
// always true. In this case, it's safe to set the local
// valid rect to zero, which means it will be clipped out
// and not affect the scene. In future, we should fix the
// accuracy issue above, so that this assumption holds, but
// it shouldn't have any noticeable effect on performance
// or memory usage (textures should never get allocated).
self.current_descriptor.local_valid_rect = self.local_tile_rect
.intersection(&ctx.local_rect)
.and_then(|r| r.intersection(&self.current_descriptor.local_valid_rect))
.unwrap_or_else(PictureRect::zero);
// The device_valid_rect is referenced during `update_content_validity` so it
// must be updated here first.
self.world_valid_rect = ctx.pic_to_world_mapper
.map(&self.current_descriptor.local_valid_rect)
.expect("bug: map local valid rect");
// The device rect is guaranteed to be aligned on a device pixel - the round
// is just to deal with float accuracy. However, the valid rect is not
// always aligned to a device pixel. To handle this, round out to get all
// required pixels, and intersect with the tile device rect.
let device_rect = (self.world_tile_rect * ctx.global_device_pixel_scale).round();
self.device_valid_rect = (self.world_valid_rect * ctx.global_device_pixel_scale)
.round_out()
.intersection(&device_rect)
.unwrap_or_else(DeviceRect::zero);
// Invalidate the tile based on the content changing.
self.update_content_validity(ctx, state, frame_context);
}
/// Called during tile cache instance post_update. Allows invalidation and dirty
/// rect calculation after primitive dependencies have been updated.
fn post_update(
&mut self,
ctx: &TilePostUpdateContext,
state: &mut TilePostUpdateState,
frame_context: &FrameVisibilityContext,
) {
// If tile is not visible, just early out from here - we don't update dependencies
// so don't want to invalidate, merge, split etc. The tile won't need to be drawn
// (and thus updated / invalidated) until it is on screen again.
if !self.is_visible {
return;
}
// If there are no primitives there is no need to draw or cache it.
// region. Cull the tile as a workaround.
if self.current_descriptor.prims.is_empty() || self.device_valid_rect.is_empty() {
// If there is a native compositor surface allocated for this (now empty) tile
// it must be freed here, otherwise the stale tile with previous contents will
// be composited. If the tile subsequently gets new primitives added to it, the
// surface will be re-allocated when it's added to the composite draw list.
if let Some(TileSurface::Texture { descriptor: SurfaceTextureDescriptor::Native { mut id, .. }, .. }) = self.surface.take() {
if let Some(id) = id.take() {
state.resource_cache.destroy_compositor_tile(id);
}
}
self.is_visible = false;
return;
}
// Check if this tile can be considered opaque. Opacity state must be updated only
// after all early out checks have been performed. Otherwise, we might miss updating
// the native surface next time this tile becomes visible.
let clipped_rect = self.current_descriptor.local_valid_rect
.intersection(&ctx.local_clip_rect)
.unwrap_or_else(PictureRect::zero);
let has_opaque_bg_color = self.background_color.map_or(false, |c| c.a >= 1.0);
let has_opaque_backdrop = ctx.backdrop.map_or(false, |b| b.opaque_rect.contains_box(&clipped_rect));
let mut is_opaque = has_opaque_bg_color || has_opaque_backdrop;
// If this tile intersects with any underlay surfaces, we need to consider it
// translucent, since it will contain an alpha cutout
for underlay in ctx.underlays {
if clipped_rect.intersects(&underlay.local_rect) {
is_opaque = false;
break;
}
}
// Set the correct z_id for this tile
self.z_id = ctx.z_id;
if is_opaque != self.is_opaque {
// If opacity changed, the native compositor surface and all tiles get invalidated.
// (this does nothing if not using native compositor mode).
// TODO(gw): This property probably changes very rarely, so it is OK to invalidate
// everything in this case. If it turns out that this isn't true, we could
// consider other options, such as per-tile opacity (natively supported
// on CoreAnimation, and supported if backed by non-virtual surfaces in
// DirectComposition).
if let Some(TileSurface::Texture { descriptor: SurfaceTextureDescriptor::Native { ref mut id, .. }, .. }) = self.surface {
if let Some(id) = id.take() {
state.resource_cache.destroy_compositor_tile(id);
}
}
// Invalidate the entire tile to force a redraw.
self.invalidate(None, InvalidationReason::SurfaceOpacityChanged);
self.is_opaque = is_opaque;
}
// Check if the selected composite mode supports dirty rect updates. For Draw composite
// mode, we can always update the content with smaller dirty rects, unless there is a
// driver bug to workaround. For native composite mode, we can only use dirty rects if
// the compositor supports partial surface updates.
let (supports_dirty_rects, supports_simple_prims) = match state.composite_state.compositor_kind {
CompositorKind::Draw { .. } => {
(frame_context.config.gpu_supports_render_target_partial_update, true)
}
CompositorKind::Native { capabilities, .. } => {
(capabilities.max_update_rects > 0, false)
}
};
// TODO(gw): Consider using smaller tiles and/or tile splits for
// native compositors that don't support dirty rects.
if supports_dirty_rects {
// Only allow splitting for normal content sized tiles
if ctx.current_tile_size == state.resource_cache.picture_textures.default_tile_size() {
let max_split_level = 3;
// Consider splitting / merging dirty regions
self.root.maybe_merge_or_split(
0,
&self.current_descriptor.prims,
max_split_level,
);
}
}
// The dirty rect will be set correctly by now. If the underlying platform
// doesn't support partial updates, and this tile isn't valid, force the dirty
// rect to be the size of the entire tile.
if !self.is_valid && !supports_dirty_rects {
self.local_dirty_rect = self.local_tile_rect;
}
// See if this tile is a simple color, in which case we can just draw
// it as a rect, and avoid allocating a texture surface and drawing it.
// TODO(gw): Initial native compositor interface doesn't support simple
// color tiles. We can definitely support this in DC, so this
// should be added as a follow up.
let is_simple_prim =
ctx.backdrop.map_or(false, |b| b.kind.is_some()) &&
self.current_descriptor.prims.len() == 1 &&
self.is_opaque &&
supports_simple_prims;
// Set up the backing surface for this tile.
let surface = if is_simple_prim {
// If we determine the tile can be represented by a color, set the
// surface unconditionally (this will drop any previously used
// texture cache backing surface).
match ctx.backdrop.unwrap().kind {
Some(BackdropKind::Color { color }) => {
TileSurface::Color {
color,
}
}
Some(BackdropKind::Clear) => {
TileSurface::Clear
}
None => {
// This should be prevented by the is_simple_prim check above.
unreachable!();
}
}
} else {
// If this tile will be backed by a surface, we want to retain
// the texture handle from the previous frame, if possible. If
// the tile was previously a color, or not set, then just set
// up a new texture cache handle.
match self.surface.take() {
Some(TileSurface::Texture { descriptor }) => {
// Reuse the existing descriptor and vis mask
TileSurface::Texture {
descriptor,
}
}
Some(TileSurface::Color { .. }) | Some(TileSurface::Clear) | None => {
// This is the case where we are constructing a tile surface that
// involves drawing to a texture. Create the correct surface
// descriptor depending on the compositing mode that will read
// the output.
let descriptor = match state.composite_state.compositor_kind {
CompositorKind::Draw { .. } => {
// For a texture cache entry, create an invalid handle that
// will be allocated when update_picture_cache is called.
SurfaceTextureDescriptor::TextureCache {
handle: None,
}
}
CompositorKind::Native { .. } => {
// Create a native surface surface descriptor, but don't allocate
// a surface yet. The surface is allocated *after* occlusion
// culling occurs, so that only visible tiles allocate GPU memory.
SurfaceTextureDescriptor::Native {
id: None,
}
}
};
TileSurface::Texture {
descriptor,
}
}
}
};
// Store the current surface backing info for use during batching.
self.surface = Some(surface);
}
}
/// Defines a key that uniquely identifies a primitive instance.
#[derive(Debug, Clone)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct PrimitiveDescriptor {
pub prim_uid: ItemUid,
pub prim_clip_box: PictureBox2D,
// TODO(gw): These two fields could be packed as a u24/u8
pub dep_offset: u32,
pub dep_count: u32,
}
impl PartialEq for PrimitiveDescriptor {
fn eq(&self, other: &Self) -> bool {
const EPSILON: f32 = 0.001;
if self.prim_uid != other.prim_uid {
return false;
}
if !self.prim_clip_box.min.x.approx_eq_eps(&other.prim_clip_box.min.x, &EPSILON) {
return false;
}
if !self.prim_clip_box.min.y.approx_eq_eps(&other.prim_clip_box.min.y, &EPSILON) {
return false;
}
if !self.prim_clip_box.max.x.approx_eq_eps(&other.prim_clip_box.max.x, &EPSILON) {
return false;
}
if !self.prim_clip_box.max.y.approx_eq_eps(&other.prim_clip_box.max.y, &EPSILON) {
return false;
}
if self.dep_count != other.dep_count {
return false;
}
true
}
}
/// Uniquely describes the content of this tile, in a way that can be
/// (reasonably) efficiently hashed and compared.
#[cfg_attr(any(feature="capture",feature="replay"), derive(Clone))]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct TileDescriptor {
/// List of primitive instance unique identifiers. The uid is guaranteed
/// to uniquely describe the content of the primitive template, while
/// the other parameters describe the clip chain and instance params.
prims: Vec<PrimitiveDescriptor>,
/// Picture space rect that contains valid pixels region of this tile.
pub local_valid_rect: PictureRect,
/// The last frame this tile had its dependencies updated (dependency updating is
/// skipped if a tile is off-screen).
last_updated_frame_id: FrameId,
/// Packed per-prim dependency information
dep_data: Vec<u8>,
}
impl TileDescriptor {
fn new() -> Self {
TileDescriptor {
local_valid_rect: PictureRect::zero(),
dep_data: Vec::new(),
prims: Vec::new(),
last_updated_frame_id: FrameId::INVALID,
}
}
/// Print debug information about this tile descriptor to a tree printer.
fn print(&self, pt: &mut dyn PrintTreePrinter) {
pt.new_level("current_descriptor".to_string());
pt.new_level("prims".to_string());
for prim in &self.prims {
pt.new_level(format!("prim uid={}", prim.prim_uid.get_uid()));
pt.add_item(format!("clip: p0={},{} p1={},{}",
prim.prim_clip_box.min.x,
prim.prim_clip_box.min.y,
prim.prim_clip_box.max.x,
prim.prim_clip_box.max.y,
));
pt.end_level();
}
pt.end_level();
pt.end_level();
}
/// Clear the dependency information for a tile, when the dependencies
/// are being rebuilt.
fn clear(&mut self) {
self.local_valid_rect = PictureRect::zero();
self.prims.clear();
self.dep_data.clear();
}
}
/// Represents the dirty region of a tile cache picture.
#[derive(Clone)]
pub struct DirtyRegion {
/// The overall dirty rect, a combination of dirty_rects
pub combined: WorldRect,
/// Spatial node of the picture cache this region represents
spatial_node_index: SpatialNodeIndex,
}
impl DirtyRegion {
/// Construct a new dirty region tracker.
pub fn new(
spatial_node_index: SpatialNodeIndex,
) -> Self {
DirtyRegion {
combined: WorldRect::zero(),
spatial_node_index,
}
}
/// Reset the dirty regions back to empty
pub fn reset(
&mut self,
spatial_node_index: SpatialNodeIndex,
) {
self.combined = WorldRect::zero();
self.spatial_node_index = spatial_node_index;
}
/// Add a dirty region to the tracker. Returns the visibility mask that corresponds to
/// this region in the tracker.
pub fn add_dirty_region(
&mut self,
rect_in_pic_space: PictureRect,
spatial_tree: &SpatialTree,
) {
let map_pic_to_world = SpaceMapper::new_with_target(
spatial_tree.root_reference_frame_index(),
self.spatial_node_index,
WorldRect::max_rect(),
spatial_tree,
);
let world_rect = map_pic_to_world
.map(&rect_in_pic_space)
.expect("bug");
// Include this in the overall dirty rect
self.combined = self.combined.union(&world_rect);
}
}
// TODO(gw): Tidy this up by:
// - Rename Clear variant to something more appropriate to what it does
// - Add an Other variant for things like opaque gradient backdrops
#[derive(Debug, Copy, Clone)]
pub enum BackdropKind {
Color {
color: ColorF,
},
Clear,
}
/// Stores information about the calculated opaque backdrop of this slice.
#[derive(Debug, Copy, Clone)]
pub struct BackdropInfo {
/// The picture space rectangle that is known to be opaque. This is used
/// to determine where subpixel AA can be used, and where alpha blending
/// can be disabled.
pub opaque_rect: PictureRect,
/// If the backdrop covers the entire slice with an opaque color, this
/// will be set and can be used as a clear color for the slice's tiles.
pub spanning_opaque_color: Option<ColorF>,
/// Kind of the backdrop
pub kind: Option<BackdropKind>,
/// The picture space rectangle of the backdrop, if kind is set.
pub backdrop_rect: PictureRect,
}
impl BackdropInfo {
fn empty() -> Self {
BackdropInfo {
opaque_rect: PictureRect::zero(),
spanning_opaque_color: None,
kind: None,
backdrop_rect: PictureRect::zero(),
}
}
}
/// Represents the native surfaces created for a picture cache, if using
/// a native compositor. An opaque and alpha surface is always created,
/// but tiles are added to a surface based on current opacity. If the
/// calculated opacity of a tile changes, the tile is invalidated and
/// attached to a different native surface. This means that we don't
/// need to invalidate the entire surface if only some tiles are changing
/// opacity. It also means we can take advantage of opaque tiles on cache
/// slices where only some of the tiles are opaque. There is an assumption
/// that creating a native surface is cheap, and only when a tile is added
/// to a surface is there a significant cost. This assumption holds true
/// for the current native compositor implementations on Windows and Mac.
pub struct NativeSurface {
/// Native surface for opaque tiles
pub opaque: NativeSurfaceId,
/// Native surface for alpha tiles
pub alpha: NativeSurfaceId,
}
/// Hash key for an external native compositor surface
#[derive(PartialEq, Eq, Hash)]
pub struct ExternalNativeSurfaceKey {
/// The YUV/RGB image keys that are used to draw this surface.
pub image_keys: [ImageKey; 3],
/// If this is not an 'external' compositor surface created via
/// Compositor::create_external_surface, this is set to the
/// current device size of the surface.
pub size: Option<DeviceIntSize>,
}
/// Information about a native compositor surface cached between frames.
pub struct ExternalNativeSurface {
/// If true, the surface was used this frame. Used for a simple form
/// of GC to remove old surfaces.
pub used_this_frame: bool,
/// The native compositor surface handle
pub native_surface_id: NativeSurfaceId,
/// List of image keys, and current image generations, that are drawn in this surface.
/// The image generations are used to check if the compositor surface is dirty and
/// needs to be updated.
pub image_dependencies: [ImageDependency; 3],
}
/// The key that identifies a tile cache instance. For now, it's simple the index of
/// the slice as it was created during scene building.
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct SliceId(usize);
impl SliceId {
pub fn new(index: usize) -> Self {
SliceId(index)
}
}
/// Information that is required to reuse or create a new tile cache. Created
/// during scene building and passed to the render backend / frame builder.
pub struct TileCacheParams {
// Index of the slice (also effectively the key of the tile cache, though we use SliceId where that matters)
pub slice: usize,
// Flags describing content of this cache (e.g. scrollbars)
pub slice_flags: SliceFlags,
// The anchoring spatial node / scroll root
pub spatial_node_index: SpatialNodeIndex,
// Optional background color of this tilecache. If present, can be used as an optimization
// to enable opaque blending and/or subpixel AA in more places.
pub background_color: Option<ColorF>,
// Node in the clip-tree that defines where we exclude clips from child prims
pub shared_clip_node_id: ClipNodeId,
// Clip leaf that is used to build the clip-chain for this tile cache.
pub shared_clip_leaf_id: Option<ClipLeafId>,
// Virtual surface sizes are always square, so this represents both the width and height
pub virtual_surface_size: i32,
// The number of compositor surfaces that are being requested for this tile cache.
// This is only a suggestion - the tile cache will clamp this as a reasonable number
// and only promote a limited number of surfaces.
pub overlay_surface_count: usize,
}
/// Defines which sub-slice (effectively a z-index) a primitive exists on within
/// a picture cache instance.
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
pub struct SubSliceIndex(u8);
impl SubSliceIndex {
pub const DEFAULT: SubSliceIndex = SubSliceIndex(0);
pub fn new(index: usize) -> Self {
SubSliceIndex(index as u8)
}
/// Return true if this sub-slice is the primary sub-slice (for now, we assume
/// that only the primary sub-slice may be opaque and support subpixel AA, for example).
pub fn is_primary(&self) -> bool {
self.0 == 0
}
/// Get an array index for this sub-slice
pub fn as_usize(&self) -> usize {
self.0 as usize
}
}
/// Wrapper struct around an external surface descriptor with a little more information
/// that the picture caching code needs.
pub struct CompositorSurface {
// External surface descriptor used by compositing logic
pub descriptor: ExternalSurfaceDescriptor,
// The compositor surface rect + any intersecting prims. Later prims that intersect
// with this must be added to the next sub-slice.
prohibited_rect: PictureRect,
// If the compositor surface content is opaque.
pub is_opaque: bool,
}
/// A SubSlice represents a potentially overlapping set of tiles within a picture cache. Most
/// picture cache instances will have only a single sub-slice. The exception to this is when
/// a picture cache has compositor surfaces, in which case sub slices are used to interleave
/// content under or order the compositor surface(s).
pub struct SubSlice {
/// Hash of tiles present in this picture.
pub tiles: FastHashMap<TileOffset, Box<Tile>>,
/// The allocated compositor surfaces for this picture cache. May be None if
/// not using native compositor, or if the surface was destroyed and needs
/// to be reallocated next time this surface contains valid tiles.
pub native_surface: Option<NativeSurface>,
/// List of compositor surfaces that have been promoted from primitives
/// in this tile cache.
pub compositor_surfaces: Vec<CompositorSurface>,
/// List of visible tiles to be composited for this subslice
pub composite_tiles: Vec<CompositeTile>,
/// Compositor descriptors of visible, opaque tiles (used by composite_state.push_surface)
pub opaque_tile_descriptors: Vec<CompositeTileDescriptor>,
/// Compositor descriptors of visible, alpha tiles (used by composite_state.push_surface)
pub alpha_tile_descriptors: Vec<CompositeTileDescriptor>,
}
impl SubSlice {
/// Construct a new sub-slice
fn new() -> Self {
SubSlice {
tiles: FastHashMap::default(),
native_surface: None,
compositor_surfaces: Vec::new(),
composite_tiles: Vec::new(),
opaque_tile_descriptors: Vec::new(),
alpha_tile_descriptors: Vec::new(),
}
}
/// Reset the list of compositor surfaces that follow this sub-slice.
/// Built per-frame, since APZ may change whether an image is suitable to be a compositor surface.
fn reset(&mut self) {
self.compositor_surfaces.clear();
self.composite_tiles.clear();
self.opaque_tile_descriptors.clear();
self.alpha_tile_descriptors.clear();
}
/// Resize the tile grid to match a new tile bounds
fn resize(&mut self, new_tile_rect: TileRect) -> FastHashMap<TileOffset, Box<Tile>> {
let mut old_tiles = mem::replace(&mut self.tiles, FastHashMap::default());
self.tiles.reserve(new_tile_rect.area() as usize);
for y in new_tile_rect.min.y .. new_tile_rect.max.y {
for x in new_tile_rect.min.x .. new_tile_rect.max.x {
let key = TileOffset::new(x, y);
let tile = old_tiles
.remove(&key)
.unwrap_or_else(|| {
Box::new(Tile::new(key))
});
self.tiles.insert(key, tile);
}
}
old_tiles
}
}
pub struct BackdropSurface {
pub id: NativeSurfaceId,
color: ColorF,
pub device_rect: DeviceRect,
}
/// Represents a cache of tiles that make up a picture primitives.
pub struct TileCacheInstance {
/// Index of the tile cache / slice for this frame builder. It's determined
/// by the setup_picture_caching method during flattening, which splits the
/// picture tree into multiple slices. It's used as a simple input to the tile
/// keys. It does mean we invalidate tiles if a new layer gets inserted / removed
/// between display lists - this seems very unlikely to occur on most pages, but
/// can be revisited if we ever notice that.
pub slice: usize,
/// Propagated information about the slice
pub slice_flags: SliceFlags,
/// The currently selected tile size to use for this cache
pub current_tile_size: DeviceIntSize,
/// The list of sub-slices in this tile cache
pub sub_slices: Vec<SubSlice>,
/// The positioning node for this tile cache.
pub spatial_node_index: SpatialNodeIndex,
/// List of opacity bindings, with some extra information
/// about whether they changed since last frame.
opacity_bindings: FastHashMap<PropertyBindingId, OpacityBindingInfo>,
/// Switch back and forth between old and new bindings hashmaps to avoid re-allocating.
old_opacity_bindings: FastHashMap<PropertyBindingId, OpacityBindingInfo>,
/// A helper to compare transforms between previous and current frame.
spatial_node_comparer: SpatialNodeComparer,
/// List of color bindings, with some extra information
/// about whether they changed since last frame.
color_bindings: FastHashMap<PropertyBindingId, ColorBindingInfo>,
/// Switch back and forth between old and new bindings hashmaps to avoid re-allocating.
old_color_bindings: FastHashMap<PropertyBindingId, ColorBindingInfo>,
/// The current dirty region tracker for this picture.
pub dirty_region: DirtyRegion,
/// Current size of tiles in picture units.
tile_size: PictureSize,
/// Tile coords of the currently allocated grid.
tile_rect: TileRect,
/// Pre-calculated versions of the tile_rect above, used to speed up the
/// calculations in get_tile_coords_for_rect.
tile_bounds_p0: TileOffset,
tile_bounds_p1: TileOffset,
/// Local rect (unclipped) of the picture this cache covers.
pub local_rect: PictureRect,
/// The local clip rect, from the shared clips of this picture.
pub local_clip_rect: PictureRect,
/// The screen rect, transformed to local picture space.
pub screen_rect_in_pic_space: PictureRect,
/// The surface index that this tile cache will be drawn into.
surface_index: SurfaceIndex,
/// The background color from the renderer. If this is set opaque, we know it's
/// fine to clear the tiles to this and allow subpixel text on the first slice.
pub background_color: Option<ColorF>,
/// Information about the calculated backdrop content of this cache.
pub backdrop: BackdropInfo,
/// The allowed subpixel mode for this surface, which depends on the detected
/// opacity of the background.
pub subpixel_mode: SubpixelMode,
// Node in the clip-tree that defines where we exclude clips from child prims
pub shared_clip_node_id: ClipNodeId,
// Clip leaf that is used to build the clip-chain for this tile cache.
pub shared_clip_leaf_id: Option<ClipLeafId>,
/// The number of frames until this cache next evaluates what tile size to use.
/// If a picture rect size is regularly changing just around a size threshold,
/// we don't want to constantly invalidate and reallocate different tile size
/// configuration each frame.
frames_until_size_eval: usize,
/// For DirectComposition, virtual surfaces don't support negative coordinates. However,
/// picture cache tile coordinates can be negative. To handle this, we apply an offset
/// to each tile in DirectComposition. We want to change this as little as possible,
/// to avoid invalidating tiles. However, if we have a picture cache tile coordinate
/// which is outside the virtual surface bounds, we must change this to allow
/// correct remapping of the coordinates passed to BeginDraw in DC.
virtual_offset: DeviceIntPoint,
/// keep around the hash map used as compare_cache to avoid reallocating it each
/// frame.
compare_cache: FastHashMap<PrimitiveComparisonKey, PrimitiveCompareResult>,
/// The currently considered tile size override. Used to check if we should
/// re-evaluate tile size, even if the frame timer hasn't expired.
tile_size_override: Option<DeviceIntSize>,
/// A cache of compositor surfaces that are retained between frames
pub external_native_surface_cache: FastHashMap<ExternalNativeSurfaceKey, ExternalNativeSurface>,
/// Current frame ID of this tile cache instance. Used for book-keeping / garbage collecting
frame_id: FrameId,
/// Registered transform in CompositeState for this picture cache
pub transform_index: CompositorTransformIndex,
/// Current transform mapping local picture space to compositor surface space
local_to_surface: ScaleOffset,
/// If true, we need to invalidate all tiles during `post_update`
invalidate_all_tiles: bool,
/// Current transform mapping compositor surface space to final device space
surface_to_device: ScaleOffset,
/// The current raster scale for tiles in this cache
current_raster_scale: f32,
/// Depth of off-screen surfaces that are currently pushed during dependency updates
current_surface_traversal_depth: usize,
/// A list of extra dirty invalidation tests that can only be checked once we
/// know the dirty rect of all tiles
deferred_dirty_tests: Vec<DeferredDirtyTest>,
/// Is there a backdrop associated with this cache
found_prims_after_backdrop: bool,
pub backdrop_surface: Option<BackdropSurface>,
/// List of underlay compositor surfaces that exist in this picture cache
pub underlays: Vec<ExternalSurfaceDescriptor>,
}
enum SurfacePromotionResult {
Failed,
Success,
}
impl TileCacheInstance {
pub fn new(params: TileCacheParams) -> Self {
// Determine how many sub-slices we need. Clamp to an arbitrary limit to ensure
// we don't create a huge number of OS compositor tiles and sub-slices.
let sub_slice_count = params.overlay_surface_count.min(MAX_COMPOSITOR_SURFACES) + 1;
let mut sub_slices = Vec::with_capacity(sub_slice_count);
for _ in 0 .. sub_slice_count {
sub_slices.push(SubSlice::new());
}
TileCacheInstance {
slice: params.slice,
slice_flags: params.slice_flags,
spatial_node_index: params.spatial_node_index,
sub_slices,
opacity_bindings: FastHashMap::default(),
old_opacity_bindings: FastHashMap::default(),
spatial_node_comparer: SpatialNodeComparer::new(),
color_bindings: FastHashMap::default(),
old_color_bindings: FastHashMap::default(),
dirty_region: DirtyRegion::new(params.spatial_node_index),
tile_size: PictureSize::zero(),
tile_rect: TileRect::zero(),
tile_bounds_p0: TileOffset::zero(),
tile_bounds_p1: TileOffset::zero(),
local_rect: PictureRect::zero(),
local_clip_rect: PictureRect::zero(),
screen_rect_in_pic_space: PictureRect::zero(),
surface_index: SurfaceIndex(0),
background_color: params.background_color,
backdrop: BackdropInfo::empty(),
subpixel_mode: SubpixelMode::Allow,
shared_clip_node_id: params.shared_clip_node_id,
shared_clip_leaf_id: params.shared_clip_leaf_id,
current_tile_size: DeviceIntSize::zero(),
frames_until_size_eval: 0,
// Default to centering the virtual offset in the middle of the DC virtual surface
virtual_offset: DeviceIntPoint::new(
params.virtual_surface_size / 2,
params.virtual_surface_size / 2,
),
compare_cache: FastHashMap::default(),
tile_size_override: None,
external_native_surface_cache: FastHashMap::default(),
frame_id: FrameId::INVALID,
transform_index: CompositorTransformIndex::INVALID,
surface_to_device: ScaleOffset::identity(),
local_to_surface: ScaleOffset::identity(),
invalidate_all_tiles: true,
current_raster_scale: 1.0,
current_surface_traversal_depth: 0,
deferred_dirty_tests: Vec::new(),
found_prims_after_backdrop: false,
backdrop_surface: None,
underlays: Vec::new(),
}
}
/// Return the total number of tiles allocated by this tile cache
pub fn tile_count(&self) -> usize {
self.tile_rect.area() as usize * self.sub_slices.len()
}
/// Trims memory held by the tile cache, such as native surfaces.
pub fn memory_pressure(&mut self, resource_cache: &mut ResourceCache) {
for sub_slice in &mut self.sub_slices {
for tile in sub_slice.tiles.values_mut() {
if let Some(TileSurface::Texture { descriptor: SurfaceTextureDescriptor::Native { ref mut id, .. }, .. }) = tile.surface {
// Reseting the id to None with take() ensures that a new
// tile will be allocated during the next frame build.
if let Some(id) = id.take() {
resource_cache.destroy_compositor_tile(id);
}
}
}
if let Some(native_surface) = sub_slice.native_surface.take() {
resource_cache.destroy_compositor_surface(native_surface.opaque);
resource_cache.destroy_compositor_surface(native_surface.alpha);
}
}
}
/// Reset this tile cache with the updated parameters from a new scene
/// that has arrived. This allows the tile cache to be retained across
/// new scenes.
pub fn prepare_for_new_scene(
&mut self,
params: TileCacheParams,
resource_cache: &mut ResourceCache,
) {
// We should only receive updated state for matching slice key
assert_eq!(self.slice, params.slice);
// Determine how many sub-slices we need, based on how many compositor surface prims are
// in the supplied primitive list.
let required_sub_slice_count = params.overlay_surface_count.min(MAX_COMPOSITOR_SURFACES) + 1;
if self.sub_slices.len() != required_sub_slice_count {
self.tile_rect = TileRect::zero();
if self.sub_slices.len() > required_sub_slice_count {
let old_sub_slices = self.sub_slices.split_off(required_sub_slice_count);
for mut sub_slice in old_sub_slices {
for tile in sub_slice.tiles.values_mut() {
if let Some(TileSurface::Texture { descriptor: SurfaceTextureDescriptor::Native { ref mut id, .. }, .. }) = tile.surface {
if let Some(id) = id.take() {
resource_cache.destroy_compositor_tile(id);
}
}
}
if let Some(native_surface) = sub_slice.native_surface {
resource_cache.destroy_compositor_surface(native_surface.opaque);
resource_cache.destroy_compositor_surface(native_surface.alpha);
}
}
} else {
while self.sub_slices.len() < required_sub_slice_count {
self.sub_slices.push(SubSlice::new());
}
}
}
// Store the parameters from the scene builder for this slice. Other
// params in the tile cache are retained and reused, or are always
// updated during pre/post_update.
self.slice_flags = params.slice_flags;
self.spatial_node_index = params.spatial_node_index;
self.background_color = params.background_color;
self.shared_clip_leaf_id = params.shared_clip_leaf_id;
self.shared_clip_node_id = params.shared_clip_node_id;
// Since the slice flags may have changed, ensure we re-evaluate the
// appropriate tile size for this cache next update.
self.frames_until_size_eval = 0;
}
/// Destroy any manually managed resources before this picture cache is
/// destroyed, such as native compositor surfaces.
pub fn destroy(
self,
resource_cache: &mut ResourceCache,
) {
for sub_slice in self.sub_slices {
if let Some(native_surface) = sub_slice.native_surface {
resource_cache.destroy_compositor_surface(native_surface.opaque);
resource_cache.destroy_compositor_surface(native_surface.alpha);
}
}
for (_, external_surface) in self.external_native_surface_cache {
resource_cache.destroy_compositor_surface(external_surface.native_surface_id)
}
if let Some(backdrop_surface) = &self.backdrop_surface {
resource_cache.destroy_compositor_surface(backdrop_surface.id);
}
}
/// Get the tile coordinates for a given rectangle.
fn get_tile_coords_for_rect(
&self,
rect: &PictureRect,
) -> (TileOffset, TileOffset) {
// Get the tile coordinates in the picture space.
let mut p0 = TileOffset::new(
(rect.min.x / self.tile_size.width).floor() as i32,
(rect.min.y / self.tile_size.height).floor() as i32,
);
let mut p1 = TileOffset::new(
(rect.max.x / self.tile_size.width).ceil() as i32,
(rect.max.y / self.tile_size.height).ceil() as i32,
);
// Clamp the tile coordinates here to avoid looping over irrelevant tiles later on.
p0.x = clamp(p0.x, self.tile_bounds_p0.x, self.tile_bounds_p1.x);
p0.y = clamp(p0.y, self.tile_bounds_p0.y, self.tile_bounds_p1.y);
p1.x = clamp(p1.x, self.tile_bounds_p0.x, self.tile_bounds_p1.x);
p1.y = clamp(p1.y, self.tile_bounds_p0.y, self.tile_bounds_p1.y);
(p0, p1)
}
/// Update transforms, opacity, color bindings and tile rects.
pub fn pre_update(
&mut self,
pic_rect: PictureRect,
surface_index: SurfaceIndex,
frame_context: &FrameVisibilityContext,
frame_state: &mut FrameVisibilityState,
) -> WorldRect {
self.surface_index = surface_index;
self.local_rect = pic_rect;
self.local_clip_rect = PictureRect::max_rect();
self.deferred_dirty_tests.clear();
self.underlays.clear();
for sub_slice in &mut self.sub_slices {
sub_slice.reset();
}
// Reset the opaque rect + subpixel mode, as they are calculated
// during the prim dependency checks.
self.backdrop = BackdropInfo::empty();
// Calculate the screen rect in picture space, for later comparison against
// backdrops, and prims potentially covering backdrops.
let pic_to_world_mapper = SpaceMapper::new_with_target(
frame_context.root_spatial_node_index,
self.spatial_node_index,
frame_context.global_screen_world_rect,
frame_context.spatial_tree,
);
self.screen_rect_in_pic_space = pic_to_world_mapper
.unmap(&frame_context.global_screen_world_rect)
.expect("unable to unmap screen rect");
// If there is a valid set of shared clips, build a clip chain instance for this,
// which will provide a local clip rect. This is useful for establishing things
// like whether the backdrop rect supplied by Gecko can be considered opaque.
if let Some(shared_clip_leaf_id) = self.shared_clip_leaf_id {
let map_local_to_surface = SpaceMapper::new(
self.spatial_node_index,
pic_rect,
);
frame_state.clip_store.set_active_clips(
self.spatial_node_index,
map_local_to_surface.ref_spatial_node_index,
shared_clip_leaf_id,
frame_context.spatial_tree,
&mut frame_state.data_stores.clip,
&frame_state.clip_tree,
);
let clip_chain_instance = frame_state.clip_store.build_clip_chain_instance(
pic_rect.cast_unit(),
&map_local_to_surface,
&pic_to_world_mapper,
frame_context.spatial_tree,
frame_state.gpu_cache,
frame_state.resource_cache,
frame_context.global_device_pixel_scale,
&frame_context.global_screen_world_rect,
&mut frame_state.data_stores.clip,
frame_state.rg_builder,
true,
);
// Ensure that if the entire picture cache is clipped out, the local
// clip rect is zero. This makes sure we don't register any occluders
// that are actually off-screen.
self.local_clip_rect = clip_chain_instance.map_or(PictureRect::zero(), |clip_chain_instance| {
clip_chain_instance.pic_coverage_rect
});
}
// Advance the current frame ID counter for this picture cache (must be done
// after any retained prev state is taken above).
self.frame_id.advance();
// Notify the spatial node comparer that a new frame has started, and the
// current reference spatial node for this tile cache.
self.spatial_node_comparer.next_frame(self.spatial_node_index);
// At the start of the frame, step through each current compositor surface
// and mark it as unused. Later, this is used to free old compositor surfaces.
// TODO(gw): In future, we might make this more sophisticated - for example,
// retaining them for >1 frame if unused, or retaining them in some
// kind of pool to reduce future allocations.
for external_native_surface in self.external_native_surface_cache.values_mut() {
external_native_surface.used_this_frame = false;
}
// Only evaluate what tile size to use fairly infrequently, so that we don't end
// up constantly invalidating and reallocating tiles if the picture rect size is
// changing near a threshold value.
if self.frames_until_size_eval == 0 ||
self.tile_size_override != frame_context.config.tile_size_override {
// Work out what size tile is appropriate for this picture cache.
let desired_tile_size = match frame_context.config.tile_size_override {
Some(tile_size_override) => {
tile_size_override
}
None => {
if self.slice_flags.contains(SliceFlags::IS_SCROLLBAR) {
if pic_rect.width() <= pic_rect.height() {
TILE_SIZE_SCROLLBAR_VERTICAL
} else {
TILE_SIZE_SCROLLBAR_HORIZONTAL
}
} else {
frame_state.resource_cache.picture_textures.default_tile_size()
}
}
};
// If the desired tile size has changed, then invalidate and drop any
// existing tiles.
if desired_tile_size != self.current_tile_size {
for sub_slice in &mut self.sub_slices {
// Destroy any native surfaces on the tiles that will be dropped due
// to resizing.
if let Some(native_surface) = sub_slice.native_surface.take() {
frame_state.resource_cache.destroy_compositor_surface(native_surface.opaque);
frame_state.resource_cache.destroy_compositor_surface(native_surface.alpha);
}
sub_slice.tiles.clear();
}
self.tile_rect = TileRect::zero();
self.current_tile_size = desired_tile_size;
}
// Reset counter until next evaluating the desired tile size. This is an
// arbitrary value.
self.frames_until_size_eval = 120;
self.tile_size_override = frame_context.config.tile_size_override;
}
// Get the complete scale-offset from local space to device space
let local_to_device = get_relative_scale_offset(
self.spatial_node_index,
frame_context.root_spatial_node_index,
frame_context.spatial_tree,
);
// Get the compositor transform, which depends on pinch-zoom mode
let mut surface_to_device = local_to_device;
if frame_context.config.low_quality_pinch_zoom {
surface_to_device.scale.x /= self.current_raster_scale;
surface_to_device.scale.y /= self.current_raster_scale;
} else {
surface_to_device.scale.x = 1.0;
surface_to_device.scale.y = 1.0;
}
// Use that compositor transform to calculate a relative local to surface
let local_to_surface = local_to_device.accumulate(&surface_to_device.inverse());
const EPSILON: f32 = 0.001;
let compositor_translation_changed =
!surface_to_device.offset.x.approx_eq_eps(&self.surface_to_device.offset.x, &EPSILON) ||
!surface_to_device.offset.y.approx_eq_eps(&self.surface_to_device.offset.y, &EPSILON);
let compositor_scale_changed =
!surface_to_device.scale.x.approx_eq_eps(&self.surface_to_device.scale.x, &EPSILON) ||
!surface_to_device.scale.y.approx_eq_eps(&self.surface_to_device.scale.y, &EPSILON);
let surface_scale_changed =
!local_to_surface.scale.x.approx_eq_eps(&self.local_to_surface.scale.x, &EPSILON) ||
!local_to_surface.scale.y.approx_eq_eps(&self.local_to_surface.scale.y, &EPSILON);
if compositor_translation_changed ||
compositor_scale_changed ||
surface_scale_changed ||
frame_context.config.force_invalidation {
frame_state.composite_state.dirty_rects_are_valid = false;
}
self.surface_to_device = surface_to_device;
self.local_to_surface = local_to_surface;
self.invalidate_all_tiles = surface_scale_changed || frame_context.config.force_invalidation;
// Do a hacky diff of opacity binding values from the last frame. This is
// used later on during tile invalidation tests.
let current_properties = frame_context.scene_properties.float_properties();
mem::swap(&mut self.opacity_bindings, &mut self.old_opacity_bindings);
self.opacity_bindings.clear();
for (id, value) in current_properties {
let changed = match self.old_opacity_bindings.get(id) {
Some(old_property) => !old_property.value.approx_eq(value),
None => true,
};
self.opacity_bindings.insert(*id, OpacityBindingInfo {
value: *value,
changed,
});
}
// Do a hacky diff of color binding values from the last frame. This is
// used later on during tile invalidation tests.
let current_properties = frame_context.scene_properties.color_properties();
mem::swap(&mut self.color_bindings, &mut self.old_color_bindings);
self.color_bindings.clear();
for (id, value) in current_properties {
let changed = match self.old_color_bindings.get(id) {
Some(old_property) => old_property.value != (*value).into(),
None => true,
};
self.color_bindings.insert(*id, ColorBindingInfo {
value: (*value).into(),
changed,
});
}
let world_tile_size = WorldSize::new(
self.current_tile_size.width as f32 / frame_context.global_device_pixel_scale.0,
self.current_tile_size.height as f32 / frame_context.global_device_pixel_scale.0,
);
self.tile_size = PictureSize::new(
world_tile_size.width / self.local_to_surface.scale.x,
world_tile_size.height / self.local_to_surface.scale.y,
);
// Inflate the needed rect a bit, so that we retain tiles that we have drawn
// but have just recently gone off-screen. This means that we avoid re-drawing
// tiles if the user is scrolling up and down small amounts, at the cost of
// a bit of extra texture memory.
let desired_rect_in_pic_space = self.screen_rect_in_pic_space
.inflate(0.0, 1.0 * self.tile_size.height);
let needed_rect_in_pic_space = desired_rect_in_pic_space
.intersection(&pic_rect)
.unwrap_or_else(Box2D::zero);
let p0 = needed_rect_in_pic_space.min;
let p1 = needed_rect_in_pic_space.max;
let x0 = (p0.x / self.tile_size.width).floor() as i32;
let x1 = (p1.x / self.tile_size.width).ceil() as i32;
let y0 = (p0.y / self.tile_size.height).floor() as i32;
let y1 = (p1.y / self.tile_size.height).ceil() as i32;
let new_tile_rect = TileRect {
min: TileOffset::new(x0, y0),
max: TileOffset::new(x1, y1),
};
// Determine whether the current bounds of the tile grid will exceed the
// bounds of the DC virtual surface, taking into account the current
// virtual offset. If so, we need to invalidate all tiles, and set up
// a new virtual offset, centered around the current tile grid.
let virtual_surface_size = frame_context.config.compositor_kind.get_virtual_surface_size();
// We only need to invalidate in this case if the underlying platform
// uses virtual surfaces.
if virtual_surface_size > 0 {
// Get the extremities of the tile grid after virtual offset is applied
let tx0 = self.virtual_offset.x + x0 * self.current_tile_size.width;
let ty0 = self.virtual_offset.y + y0 * self.current_tile_size.height;
let tx1 = self.virtual_offset.x + (x1+1) * self.current_tile_size.width;
let ty1 = self.virtual_offset.y + (y1+1) * self.current_tile_size.height;
let need_new_virtual_offset = tx0 < 0 ||
ty0 < 0 ||
tx1 >= virtual_surface_size ||
ty1 >= virtual_surface_size;
if need_new_virtual_offset {
// Calculate a new virtual offset, centered around the middle of the
// current tile grid. This means we won't need to invalidate and get
// a new offset for a long time!
self.virtual_offset = DeviceIntPoint::new(
(virtual_surface_size/2) - ((x0 + x1) / 2) * self.current_tile_size.width,
(virtual_surface_size/2) - ((y0 + y1) / 2) * self.current_tile_size.height,
);
// Invalidate all native tile surfaces. They will be re-allocated next time
// they are scheduled to be rasterized.
for sub_slice in &mut self.sub_slices {
for tile in sub_slice.tiles.values_mut() {
if let Some(TileSurface::Texture { descriptor: SurfaceTextureDescriptor::Native { ref mut id, .. }, .. }) = tile.surface {
if let Some(id) = id.take() {
frame_state.resource_cache.destroy_compositor_tile(id);
tile.surface = None;
// Invalidate the entire tile to force a redraw.
// TODO(gw): Add a new invalidation reason for virtual offset changing
tile.invalidate(None, InvalidationReason::CompositorKindChanged);
}
}
}
// Destroy the native virtual surfaces. They will be re-allocated next time a tile
// that references them is scheduled to draw.
if let Some(native_surface) = sub_slice.native_surface.take() {
frame_state.resource_cache.destroy_compositor_surface(native_surface.opaque);
frame_state.resource_cache.destroy_compositor_surface(native_surface.alpha);
}
}
}
}
// Rebuild the tile grid if the picture cache rect has changed.
if new_tile_rect != self.tile_rect {
for sub_slice in &mut self.sub_slices {
let mut old_tiles = sub_slice.resize(new_tile_rect);
// When old tiles that remain after the loop, dirty rects are not valid.
if !old_tiles.is_empty() {
frame_state.composite_state.dirty_rects_are_valid = false;
}
// Any old tiles that remain after the loop above are going to be dropped. For
// simple composite mode, the texture cache handle will expire and be collected
// by the texture cache. For native compositor mode, we need to explicitly
// invoke a callback to the client to destroy that surface.
frame_state.composite_state.destroy_native_tiles(
old_tiles.values_mut(),
frame_state.resource_cache,
);
}
}
// This is duplicated information from tile_rect, but cached here to avoid
// redundant calculations during get_tile_coords_for_rect
self.tile_bounds_p0 = TileOffset::new(x0, y0);
self.tile_bounds_p1 = TileOffset::new(x1, y1);
self.tile_rect = new_tile_rect;
let mut world_culling_rect = WorldRect::zero();
let mut ctx = TilePreUpdateContext {
pic_to_world_mapper,
background_color: self.background_color,
global_screen_world_rect: frame_context.global_screen_world_rect,
tile_size: self.tile_size,
frame_id: self.frame_id,
};
// Pre-update each tile
for sub_slice in &mut self.sub_slices {
for tile in sub_slice.tiles.values_mut() {
tile.pre_update(&ctx);
// Only include the tiles that are currently in view into the world culling
// rect. This is a very important optimization for a couple of reasons:
// (1) Primitives that intersect with tiles in the grid that are not currently
// visible can be skipped from primitive preparation, clip chain building
// and tile dependency updates.
// (2) When we need to allocate an off-screen surface for a child picture (for
// example a CSS filter) we clip the size of the GPU surface to the world
// culling rect below (to ensure we draw enough of it to be sampled by any
// tiles that reference it). Making the world culling rect only affected
// by visible tiles (rather than the entire virtual tile display port) can
// result in allocating _much_ smaller GPU surfaces for cases where the
// true off-screen surface size is very large.
if tile.is_visible {
world_culling_rect = world_culling_rect.union(&tile.world_tile_rect);
}
}
// The background color can only be applied to the first sub-slice.
ctx.background_color = None;
}
// If compositor mode is changed, need to drop all incompatible tiles.
match frame_context.config.compositor_kind {
CompositorKind::Draw { .. } => {
for sub_slice in &mut self.sub_slices {
for tile in sub_slice.tiles.values_mut() {
if let Some(TileSurface::Texture { descriptor: SurfaceTextureDescriptor::Native { ref mut id, .. }, .. }) = tile.surface {
if let Some(id) = id.take() {
frame_state.resource_cache.destroy_compositor_tile(id);
}
tile.surface = None;
// Invalidate the entire tile to force a redraw.
tile.invalidate(None, InvalidationReason::CompositorKindChanged);
}
}
if let Some(native_surface) = sub_slice.native_surface.take() {
frame_state.resource_cache.destroy_compositor_surface(native_surface.opaque);
frame_state.resource_cache.destroy_compositor_surface(native_surface.alpha);
}
}
for (_, external_surface) in self.external_native_surface_cache.drain() {
frame_state.resource_cache.destroy_compositor_surface(external_surface.native_surface_id)
}
}
CompositorKind::Native { .. } => {
// This could hit even when compositor mode is not changed,
// then we need to check if there are incompatible tiles.
for sub_slice in &mut self.sub_slices {
for tile in sub_slice.tiles.values_mut() {
if let Some(TileSurface::Texture { descriptor: SurfaceTextureDescriptor::TextureCache { .. }, .. }) = tile.surface {
tile.surface = None;
// Invalidate the entire tile to force a redraw.
tile.invalidate(None, InvalidationReason::CompositorKindChanged);
}
}
}
}
}
world_culling_rect
}
fn can_promote_to_surface(
&mut self,
flags: PrimitiveFlags,
prim_clip_chain: &ClipChainInstance,
prim_spatial_node_index: SpatialNodeIndex,
is_root_tile_cache: bool,
sub_slice_index: usize,
surface_kind: CompositorSurfaceKind,
frame_context: &FrameVisibilityContext,
) -> SurfacePromotionResult {
// Check if this primitive _wants_ to be promoted to a compositor surface.
if !flags.contains(PrimitiveFlags::PREFER_COMPOSITOR_SURFACE) {
return SurfacePromotionResult::Failed;
}
// Each strategy has different restrictions on whether we can promote
match surface_kind {
CompositorSurfaceKind::Overlay => {
// For now, only support a small (arbitrary) number of compositor surfaces.
// Non-opaque compositor surfaces require sub-slices, as they are drawn
// as overlays.
if sub_slice_index == self.sub_slices.len() - 1 {
return SurfacePromotionResult::Failed;
}
// If a complex clip is being applied to this primitive, it can't be
// promoted directly to a compositor surface unless it's opaque (in
// which case we draw as an underlay + alpha cutout)
if prim_clip_chain.needs_mask {
return SurfacePromotionResult::Failed;
}
}
CompositorSurfaceKind::Underlay => {
// Underlay strategy relies on the slice being opaque if a mask is needed,
// and only one underlay can rely on a mask.
if prim_clip_chain.needs_mask && (self.backdrop.kind.is_none() || !self.underlays.is_empty()) {
return SurfacePromotionResult::Failed;
}
}
CompositorSurfaceKind::Blit => unreachable!(),
}
// If not on the root picture cache, it has some kind of
// complex effect (such as a filter, mix-blend-mode or 3d transform).
if !is_root_tile_cache {
return SurfacePromotionResult::Failed;
}
let mapper : SpaceMapper<PicturePixel, WorldPixel> = SpaceMapper::new_with_target(
frame_context.root_spatial_node_index,
prim_spatial_node_index,
frame_context.global_screen_world_rect,
&frame_context.spatial_tree);
let transform = mapper.get_transform();
if !transform.is_2d_scale_translation() {
return SurfacePromotionResult::Failed;
}
if self.slice_flags.contains(SliceFlags::IS_ATOMIC) {
return SurfacePromotionResult::Failed;
}
SurfacePromotionResult::Success
}
fn setup_compositor_surfaces_yuv(
&mut self,
sub_slice_index: usize,
prim_info: &mut PrimitiveDependencyInfo,
flags: PrimitiveFlags,
local_prim_rect: LayoutRect,
prim_spatial_node_index: SpatialNodeIndex,
pic_coverage_rect: PictureRect,
frame_context: &FrameVisibilityContext,
image_dependencies: &[ImageDependency;3],
api_keys: &[ImageKey; 3],
resource_cache: &mut ResourceCache,
composite_state: &mut CompositeState,
gpu_cache: &mut GpuCache,
image_rendering: ImageRendering,
color_depth: ColorDepth,
color_space: YuvRangedColorSpace,
format: YuvFormat,
) -> bool {
for &key in api_keys {
if key != ImageKey::DUMMY {
// TODO: See comment in setup_compositor_surfaces_rgb.
resource_cache.request_image(ImageRequest {
key,
rendering: image_rendering,
tile: None,
},
gpu_cache,
);
}
}
self.setup_compositor_surfaces_impl(
sub_slice_index,
prim_info,
flags,
local_prim_rect,
prim_spatial_node_index,
pic_coverage_rect,
frame_context,
ExternalSurfaceDependency::Yuv {
image_dependencies: *image_dependencies,
color_space,
format,
channel_bit_depth: color_depth.bit_depth(),
},
api_keys,
resource_cache,
composite_state,
image_rendering,
true,
CompositorSurfaceKind::Underlay,
)
}
fn setup_compositor_surfaces_rgb(
&mut self,
sub_slice_index: usize,
prim_info: &mut PrimitiveDependencyInfo,
flags: PrimitiveFlags,
local_prim_rect: LayoutRect,
prim_spatial_node_index: SpatialNodeIndex,
pic_coverage_rect: PictureRect,
frame_context: &FrameVisibilityContext,
image_dependency: ImageDependency,
api_key: ImageKey,
resource_cache: &mut ResourceCache,
composite_state: &mut CompositeState,
gpu_cache: &mut GpuCache,
image_rendering: ImageRendering,
is_opaque: bool,
surface_kind: CompositorSurfaceKind,
) -> bool {
let mut api_keys = [ImageKey::DUMMY; 3];
api_keys[0] = api_key;
// TODO: The picture compositing code requires images promoted
// into their own picture cache slices to be requested every
// frame even if they are not visible. However the image updates
// are only reached on the prepare pass for visible primitives.
// So we make sure to trigger an image request when promoting
// the image here.
resource_cache.request_image(ImageRequest {
key: api_key,
rendering: image_rendering,
tile: None,
},
gpu_cache,
);
self.setup_compositor_surfaces_impl(
sub_slice_index,
prim_info,
flags,
local_prim_rect,
prim_spatial_node_index,
pic_coverage_rect,
frame_context,
ExternalSurfaceDependency::Rgb {
image_dependency,
},
&api_keys,
resource_cache,
composite_state,
image_rendering,
is_opaque,
surface_kind,
)
}
// returns false if composition is not available for this surface,
// and the non-compositor path should be used to draw it instead.
fn setup_compositor_surfaces_impl(
&mut self,
sub_slice_index: usize,
prim_info: &mut PrimitiveDependencyInfo,
flags: PrimitiveFlags,
local_prim_rect: LayoutRect,
prim_spatial_node_index: SpatialNodeIndex,
pic_coverage_rect: PictureRect,
frame_context: &FrameVisibilityContext,
dependency: ExternalSurfaceDependency,
api_keys: &[ImageKey; 3],
resource_cache: &mut ResourceCache,
composite_state: &mut CompositeState,
image_rendering: ImageRendering,
is_opaque: bool,
surface_kind: CompositorSurfaceKind,
) -> bool {
let map_local_to_surface = SpaceMapper::new_with_target(
self.spatial_node_index,
prim_spatial_node_index,
self.local_rect,
frame_context.spatial_tree,
);
// Map the primitive local rect into picture space.
let prim_rect = match map_local_to_surface.map(&local_prim_rect) {
Some(rect) => rect,
None => return true,
};
// If the rect is invalid, no need to create dependencies.
if prim_rect.is_empty() {
return true;
}
let pic_to_world_mapper = SpaceMapper::new_with_target(
frame_context.root_spatial_node_index,
self.spatial_node_index,
frame_context.global_screen_world_rect,
frame_context.spatial_tree,
);
let world_clip_rect = pic_to_world_mapper
.map(&prim_info.prim_clip_box)
.expect("bug: unable to map clip to world space");
let is_visible = world_clip_rect.intersects(&frame_context.global_screen_world_rect);
if !is_visible {
return true;
}
let prim_offset = ScaleOffset::from_offset(local_prim_rect.min.to_vector().cast_unit());
let local_prim_to_device = get_relative_scale_offset(
prim_spatial_node_index,
frame_context.root_spatial_node_index,
frame_context.spatial_tree,
);
let normalized_prim_to_device = prim_offset.accumulate(&local_prim_to_device);
let local_to_surface = ScaleOffset::identity();
let surface_to_device = normalized_prim_to_device;
// If this primitive is an external image, and supports being used
// directly by a native compositor, then lookup the external image id
// so we can pass that through.
let mut external_image_id = if flags.contains(PrimitiveFlags::SUPPORTS_EXTERNAL_COMPOSITOR_SURFACE)
&& image_rendering == ImageRendering::Auto {
resource_cache.get_image_properties(api_keys[0])
.and_then(|properties| properties.external_image)
.and_then(|image| Some(image.id))
} else {
None
};
if let CompositorKind::Native { capabilities, .. } = composite_state.compositor_kind {
if external_image_id.is_some() &&
!capabilities.supports_external_compositor_surface_negative_scaling &&
(surface_to_device.scale.x < 0.0 || surface_to_device.scale.y < 0.0) {
external_image_id = None;
}
}
let compositor_transform_index = composite_state.register_transform(
local_to_surface,
surface_to_device,
);
let surface_size = composite_state.get_surface_rect(
&local_prim_rect,
&local_prim_rect,
compositor_transform_index,
).size();
let clip_rect = (world_clip_rect * frame_context.global_device_pixel_scale).round();
if surface_size.width >= MAX_COMPOSITOR_SURFACES_SIZE ||
surface_size.height >= MAX_COMPOSITOR_SURFACES_SIZE {
return false;
}
// When using native compositing, we need to find an existing native surface
// handle to use, or allocate a new one. For existing native surfaces, we can
// also determine whether this needs to be updated, depending on whether the
// image generation(s) of the planes have changed since last composite.
let (native_surface_id, update_params) = match composite_state.compositor_kind {
CompositorKind::Draw { .. } => {
(None, None)
}
CompositorKind::Native { .. } => {
let native_surface_size = surface_size.to_i32();
let key = ExternalNativeSurfaceKey {
image_keys: *api_keys,
size: if external_image_id.is_some() { None } else { Some(native_surface_size) },
};
let native_surface = self.external_native_surface_cache
.entry(key)
.or_insert_with(|| {
// No existing surface, so allocate a new compositor surface.
let native_surface_id = match external_image_id {
Some(_external_image) => {
// If we have a suitable external image, then create an external
// surface to attach to.
resource_cache.create_compositor_external_surface(is_opaque)
}
None => {
// Otherwise create a normal compositor surface and a single
// compositor tile that covers the entire surface.
let native_surface_id =
resource_cache.create_compositor_surface(
DeviceIntPoint::zero(),
native_surface_size,
is_opaque,
);
let tile_id = NativeTileId {
surface_id: native_surface_id,
x: 0,
y: 0,
};
resource_cache.create_compositor_tile(tile_id);
native_surface_id
}
};
ExternalNativeSurface {
used_this_frame: true,
native_surface_id,
image_dependencies: [ImageDependency::INVALID; 3],
}
});
// Mark that the surface is referenced this frame so that the
// backing native surface handle isn't freed.
native_surface.used_this_frame = true;
let update_params = match external_image_id {
Some(external_image) => {
// If this is an external image surface, then there's no update
// to be done. Just attach the current external image to the surface
// and we're done.
resource_cache.attach_compositor_external_image(
native_surface.native_surface_id,
external_image,
);
None
}
None => {
// If the image dependencies match, there is no need to update
// the backing native surface.
match dependency {
ExternalSurfaceDependency::Yuv{ image_dependencies, .. } => {
if image_dependencies == native_surface.image_dependencies {
None
} else {
Some(native_surface_size)
}
},
ExternalSurfaceDependency::Rgb{ image_dependency, .. } => {
if image_dependency == native_surface.image_dependencies[0] {
None
} else {
Some(native_surface_size)
}
},
}
}
};
(Some(native_surface.native_surface_id), update_params)
}
};
let descriptor = ExternalSurfaceDescriptor {
local_surface_size: local_prim_rect.size(),
local_rect: prim_rect,
local_clip_rect: prim_info.prim_clip_box,
dependency,
image_rendering,
clip_rect,
transform_index: compositor_transform_index,
z_id: ZBufferId::invalid(),
native_surface_id,
update_params,
};
// If the surface is opaque, we can draw it an an underlay (which avoids
// additional sub-slice surfaces, and supports clip masks)
match surface_kind {
CompositorSurfaceKind::Underlay => {
self.underlays.push(descriptor);
}
CompositorSurfaceKind::Overlay => {
// For compositor surfaces, if we didn't find an earlier sub-slice to add to,
// we know we can append to the current slice.
assert!(sub_slice_index < self.sub_slices.len() - 1);
let sub_slice = &mut self.sub_slices[sub_slice_index];
// Each compositor surface allocates a unique z-id
sub_slice.compositor_surfaces.push(CompositorSurface {
prohibited_rect: pic_coverage_rect,
is_opaque,
descriptor,
});
}
CompositorSurfaceKind::Blit => unreachable!(),
}
true
}
/// Push an estimated rect for an off-screen surface during dependency updates. This is
/// a workaround / hack that allows the picture cache code to know when it should be
/// processing primitive dependencies as a single atomic unit. In future, we aim to remove
/// this hack by having the primitive dependencies stored _within_ each owning picture.
/// This is part of the work required to support child picture caching anyway!
pub fn push_surface(
&mut self,
estimated_local_rect: LayoutRect,
surface_spatial_node_index: SpatialNodeIndex,
spatial_tree: &SpatialTree,
) {
// Only need to evaluate sub-slice regions if we have compositor surfaces present
if self.current_surface_traversal_depth == 0 && self.sub_slices.len() > 1 {
let map_local_to_surface = SpaceMapper::new_with_target(
self.spatial_node_index,
surface_spatial_node_index,
self.local_rect,
spatial_tree,
);
if let Some(pic_rect) = map_local_to_surface.map(&estimated_local_rect) {
// Find the first sub-slice we can add this primitive to (we want to add
// prims to the primary surface if possible, so they get subpixel AA).
for sub_slice in &mut self.sub_slices {
let mut intersects_prohibited_region = false;
for surface in &mut sub_slice.compositor_surfaces {
if pic_rect.intersects(&surface.prohibited_rect) {
surface.prohibited_rect = surface.prohibited_rect.union(&pic_rect);
intersects_prohibited_region = true;
}
}
if !intersects_prohibited_region {
break;
}
}
}
}
self.current_surface_traversal_depth += 1;
}
/// Pop an off-screen surface off the stack during dependency updates
pub fn pop_surface(&mut self) {
self.current_surface_traversal_depth -= 1;
}
/// Update the dependencies for each tile for a given primitive instance.
pub fn update_prim_dependencies(
&mut self,
prim_instance: &mut PrimitiveInstance,
prim_spatial_node_index: SpatialNodeIndex,
local_prim_rect: LayoutRect,
frame_context: &FrameVisibilityContext,
data_stores: &DataStores,
clip_store: &ClipStore,
pictures: &[PicturePrimitive],
resource_cache: &mut ResourceCache,
color_bindings: &ColorBindingStorage,
surface_stack: &[(PictureIndex, SurfaceIndex)],
composite_state: &mut CompositeState,
gpu_cache: &mut GpuCache,
scratch: &mut PrimitiveScratchBuffer,
is_root_tile_cache: bool,
surfaces: &mut [SurfaceInfo],
) {
// This primitive exists on the last element on the current surface stack.
profile_scope!("update_prim_dependencies");
let prim_surface_index = surface_stack.last().unwrap().1;
let prim_clip_chain = &prim_instance.vis.clip_chain;
// Accumulate the exact (clipped) local rect in to the parent surface
let surface = &mut surfaces[prim_surface_index.0];
surface.clipped_local_rect = surface.clipped_local_rect.union(&prim_clip_chain.pic_coverage_rect);
// If the primitive is directly drawn onto this picture cache surface, then
// the pic_coverage_rect is in the same space. If not, we need to map it from
// the surface space into the picture cache space.
let on_picture_surface = prim_surface_index == self.surface_index;
let pic_coverage_rect = if on_picture_surface {
prim_clip_chain.pic_coverage_rect
} else {
// We want to get the rect in the tile cache surface space that this primitive
// occupies, in order to enable correct invalidation regions. Each surface
// that exists in the chain between this primitive and the tile cache surface
// may have an arbitrary inflation factor (for example, in the case of a series
// of nested blur elements). To account for this, step through the current
// surface stack, mapping the primitive rect into each surface space, including
// the inflation factor from each intermediate surface.
let mut current_pic_coverage_rect = prim_clip_chain.pic_coverage_rect;
let mut current_spatial_node_index = surfaces[prim_surface_index.0]
.surface_spatial_node_index;
for (pic_index, surface_index) in surface_stack.iter().rev() {
let surface = &surfaces[surface_index.0];
let pic = &pictures[pic_index.0];
let map_local_to_surface = SpaceMapper::new_with_target(
surface.surface_spatial_node_index,
current_spatial_node_index,
surface.unclipped_local_rect,
frame_context.spatial_tree,
);
// Map the rect into the parent surface, and inflate if this surface requires
// it. If the rect can't be mapping (e.g. due to an invalid transform) then
// just bail out from the dependencies and cull this primitive.
current_pic_coverage_rect = match map_local_to_surface.map(¤t_pic_coverage_rect) {
Some(rect) => {
// TODO(gw): The casts here are a hack. We have some interface inconsistencies
// between layout/picture rects which don't really work with the
// current unit system, since sometimes the local rect of a picture
// is a LayoutRect, and sometimes it's a PictureRect. Consider how
// we can improve this?
pic.composite_mode.as_ref().unwrap().get_coverage(
surface,
Some(rect.cast_unit()),
).cast_unit()
}
None => {
return;
}
};
current_spatial_node_index = surface.surface_spatial_node_index;
}
current_pic_coverage_rect
};
// Get the tile coordinates in the picture space.
let (p0, p1) = self.get_tile_coords_for_rect(&pic_coverage_rect);
// If the primitive is outside the tiling rects, it's known to not
// be visible.
if p0.x == p1.x || p0.y == p1.y {
return;
}
// Build the list of resources that this primitive has dependencies on.
let mut prim_info = PrimitiveDependencyInfo::new(
prim_instance.uid(),
pic_coverage_rect,
);
let mut sub_slice_index = self.sub_slices.len() - 1;
// Only need to evaluate sub-slice regions if we have compositor surfaces present
if sub_slice_index > 0 {
// Find the first sub-slice we can add this primitive to (we want to add
// prims to the primary surface if possible, so they get subpixel AA).
for (i, sub_slice) in self.sub_slices.iter_mut().enumerate() {
let mut intersects_prohibited_region = false;
for surface in &mut sub_slice.compositor_surfaces {
if pic_coverage_rect.intersects(&surface.prohibited_rect) {
surface.prohibited_rect = surface.prohibited_rect.union(&pic_coverage_rect);
intersects_prohibited_region = true;
}
}
if !intersects_prohibited_region {
sub_slice_index = i;
break;
}
}
}
// Include the prim spatial node, if differs relative to cache root.
if prim_spatial_node_index != self.spatial_node_index {
prim_info.spatial_nodes.push(prim_spatial_node_index);
}
// If there was a clip chain, add any clip dependencies to the list for this tile.
let clip_instances = &clip_store
.clip_node_instances[prim_clip_chain.clips_range.to_range()];
for clip_instance in clip_instances {
let clip = &data_stores.clip[clip_instance.handle];
prim_info.clips.push(clip_instance.handle.uid());
// If the clip has the same spatial node, the relative transform
// will always be the same, so there's no need to depend on it.
if clip.item.spatial_node_index != self.spatial_node_index
&& !prim_info.spatial_nodes.contains(&clip.item.spatial_node_index) {
prim_info.spatial_nodes.push(clip.item.spatial_node_index);
}
}
// Certain primitives may select themselves to be a backdrop candidate, which is
// then applied below.
let mut backdrop_candidate = None;
// For pictures, we don't (yet) know the valid clip rect, so we can't correctly
// use it to calculate the local bounding rect for the tiles. If we include them
// then we may calculate a bounding rect that is too large, since it won't include
// the clip bounds of the picture. Excluding them from the bounding rect here
// fixes any correctness issues (the clips themselves are considered when we
// consider the bounds of the primitives that are *children* of the picture),
// however it does potentially result in some un-necessary invalidations of a
// tile (in cases where the picture local rect affects the tile, but the clip
// rect eventually means it doesn't affect that tile).
// TODO(gw): Get picture clips earlier (during the initial picture traversal
// pass) so that we can calculate these correctly.
match prim_instance.kind {
PrimitiveInstanceKind::Picture { pic_index,.. } => {
// Pictures can depend on animated opacity bindings.
let pic = &pictures[pic_index.0];
if let Some(PictureCompositeMode::Filter(Filter::Opacity(binding, _))) = pic.composite_mode {
prim_info.opacity_bindings.push(binding.into());
}
}
PrimitiveInstanceKind::Rectangle { data_handle, color_binding_index, .. } => {
// Rectangles can only form a backdrop candidate if they are known opaque.
// TODO(gw): We could resolve the opacity binding here, but the common
// case for background rects is that they don't have animated opacity.
let color = match data_stores.prim[data_handle].kind {
PrimitiveTemplateKind::Rectangle { color, .. } => {
frame_context.scene_properties.resolve_color(&color)
}
_ => unreachable!(),
};
if color.a >= 1.0 {
backdrop_candidate = Some(BackdropInfo {
opaque_rect: pic_coverage_rect,
spanning_opaque_color: None,
kind: Some(BackdropKind::Color { color }),
backdrop_rect: pic_coverage_rect,
});
}
if color_binding_index != ColorBindingIndex::INVALID {
prim_info.color_binding = Some(color_bindings[color_binding_index].into());
}
}
PrimitiveInstanceKind::Image { data_handle, ref mut compositor_surface_kind, .. } => {
let image_key = &data_stores.image[data_handle];
let image_data = &image_key.kind;
// For now, assume that for compositor surface purposes, any RGBA image may be
// translucent. See the comment in `add_prim` in this source file for more
// details. We'll leave the `is_opaque` code branches here, but disabled, as
// in future we will want to support this case correctly.
let mut is_opaque = false;
if let Some(image_properties) = resource_cache.get_image_properties(image_data.key) {
// For an image to be a possible opaque backdrop, it must:
// - Have a valid, opaque image descriptor
// - Not use tiling (since they can fail to draw)
// - Not having any spacing / padding
// - Have opaque alpha in the instance (flattened) color
if image_properties.descriptor.is_opaque() &&
image_properties.tiling.is_none() &&
image_data.tile_spacing == LayoutSize::zero() &&
image_data.color.a >= 1.0 {
backdrop_candidate = Some(BackdropInfo {
opaque_rect: pic_coverage_rect,
spanning_opaque_color: None,
kind: None,
backdrop_rect: PictureRect::zero(),
});
}
is_opaque = image_properties.descriptor.is_opaque();
}
let mut promote_to_surface = false;
match self.can_promote_to_surface(image_key.common.flags,
prim_clip_chain,
prim_spatial_node_index,
is_root_tile_cache,
sub_slice_index,
CompositorSurfaceKind::Overlay,
frame_context) {
SurfacePromotionResult::Failed => {
}
SurfacePromotionResult::Success => {
promote_to_surface = true;
}
}
// Native OS compositors (DC and CA, at least) support premultiplied alpha
// only. If we have an image that's not pre-multiplied alpha, we can't promote it.
if image_data.alpha_type == AlphaType::Alpha {
promote_to_surface = false;
}
if promote_to_surface {
promote_to_surface = self.setup_compositor_surfaces_rgb(
sub_slice_index,
&mut prim_info,
image_key.common.flags,
local_prim_rect,
prim_spatial_node_index,
pic_coverage_rect,
frame_context,
ImageDependency {
key: image_data.key,
generation: resource_cache.get_image_generation(image_data.key),
},
image_data.key,
resource_cache,
composite_state,
gpu_cache,
image_data.image_rendering,
is_opaque,
CompositorSurfaceKind::Overlay,
);
}
if promote_to_surface {
*compositor_surface_kind = CompositorSurfaceKind::Overlay;
prim_instance.vis.state = VisibilityState::Culled;
return;
} else {
*compositor_surface_kind = CompositorSurfaceKind::Blit;
prim_info.images.push(ImageDependency {
key: image_data.key,
generation: resource_cache.get_image_generation(image_data.key),
});
}
}
PrimitiveInstanceKind::YuvImage { data_handle, ref mut compositor_surface_kind, .. } => {
let prim_data = &data_stores.yuv_image[data_handle];
let mut promote_to_surface = match self.can_promote_to_surface(
prim_data.common.flags,
prim_clip_chain,
prim_spatial_node_index,
is_root_tile_cache,
sub_slice_index,
CompositorSurfaceKind::Underlay,
frame_context) {
SurfacePromotionResult::Failed => false,
SurfacePromotionResult::Success => true,
};
// TODO(gw): When we support RGBA images for external surfaces, we also
// need to check if opaque (YUV images are implicitly opaque).
// If this primitive is being promoted to a surface, construct an external
// surface descriptor for use later during batching and compositing. We only
// add the image keys for this primitive as a dependency if this is _not_
// a promoted surface, since we don't want the tiles to invalidate when the
// video content changes, if it's a compositor surface!
if promote_to_surface {
// Build dependency for each YUV plane, with current image generation for
// later detection of when the composited surface has changed.
let mut image_dependencies = [ImageDependency::INVALID; 3];
for (key, dep) in prim_data.kind.yuv_key.iter().cloned().zip(image_dependencies.iter_mut()) {
*dep = ImageDependency {
key,
generation: resource_cache.get_image_generation(key),
}
}
promote_to_surface = self.setup_compositor_surfaces_yuv(
sub_slice_index,
&mut prim_info,
prim_data.common.flags,
local_prim_rect,
prim_spatial_node_index,
pic_coverage_rect,
frame_context,
&image_dependencies,
&prim_data.kind.yuv_key,
resource_cache,
composite_state,
gpu_cache,
prim_data.kind.image_rendering,
prim_data.kind.color_depth,
prim_data.kind.color_space.with_range(prim_data.kind.color_range),
prim_data.kind.format,
);
}
// Store on the YUV primitive instance whether this is a promoted surface.
// This is used by the batching code to determine whether to draw the
// image to the content tiles, or just a transparent z-write.
if promote_to_surface {
*compositor_surface_kind = CompositorSurfaceKind::Underlay;
} else {
*compositor_surface_kind = CompositorSurfaceKind::Blit;
prim_info.images.extend(
prim_data.kind.yuv_key.iter().map(|key| {
ImageDependency {
key: *key,
generation: resource_cache.get_image_generation(*key),
}
})
);
}
}
PrimitiveInstanceKind::ImageBorder { data_handle, .. } => {
let border_data = &data_stores.image_border[data_handle].kind;
prim_info.images.push(ImageDependency {
key: border_data.request.key,
generation: resource_cache.get_image_generation(border_data.request.key),
});
}
PrimitiveInstanceKind::Clear { .. } => {
backdrop_candidate = Some(BackdropInfo {
opaque_rect: pic_coverage_rect,
spanning_opaque_color: None,
kind: Some(BackdropKind::Clear),
backdrop_rect: pic_coverage_rect,
});
}
PrimitiveInstanceKind::LinearGradient { data_handle, .. }
| PrimitiveInstanceKind::CachedLinearGradient { data_handle, .. } => {
let gradient_data = &data_stores.linear_grad[data_handle];
if gradient_data.stops_opacity.is_opaque
&& gradient_data.tile_spacing == LayoutSize::zero()
{
backdrop_candidate = Some(BackdropInfo {
opaque_rect: pic_coverage_rect,
spanning_opaque_color: None,
kind: None,
backdrop_rect: PictureRect::zero(),
});
}
}
PrimitiveInstanceKind::ConicGradient { data_handle, .. } => {
let gradient_data = &data_stores.conic_grad[data_handle];
if gradient_data.stops_opacity.is_opaque
&& gradient_data.tile_spacing == LayoutSize::zero()
{
backdrop_candidate = Some(BackdropInfo {
opaque_rect: pic_coverage_rect,
spanning_opaque_color: None,
kind: None,
backdrop_rect: PictureRect::zero(),
});
}
}
PrimitiveInstanceKind::RadialGradient { data_handle, .. } => {
let gradient_data = &data_stores.radial_grad[data_handle];
if gradient_data.stops_opacity.is_opaque
&& gradient_data.tile_spacing == LayoutSize::zero()
{
backdrop_candidate = Some(BackdropInfo {
opaque_rect: pic_coverage_rect,
spanning_opaque_color: None,
kind: None,
backdrop_rect: PictureRect::zero(),
});
}
}
PrimitiveInstanceKind::BackdropCapture { .. } => {}
PrimitiveInstanceKind::BackdropRender { pic_index, .. } => {
// If the area that the backdrop covers in the space of the surface it draws on
// is empty, skip any sub-graph processing. This is not just a performance win,
// it also ensures that we don't do a deferred dirty test that invalidates a tile
// even if the tile isn't actually dirty, which can cause panics later in the
// WR pipeline.
if !pic_coverage_rect.is_empty() {
// Mark that we need the sub-graph this render depends on so that
// we don't skip it during the prepare pass
scratch.required_sub_graphs.insert(pic_index);
// If this is a sub-graph, register the bounds on any affected tiles
// so we know how much to expand the content tile by.
let sub_slice = &mut self.sub_slices[sub_slice_index];
let mut surface_info = Vec::new();
for (pic_index, surface_index) in surface_stack.iter().rev() {
let pic = &pictures[pic_index.0];
surface_info.push((pic.composite_mode.as_ref().unwrap().clone(), *surface_index));
}
for y in p0.y .. p1.y {
for x in p0.x .. p1.x {
let key = TileOffset::new(x, y);
let tile = sub_slice.tiles.get_mut(&key).expect("bug: no tile");
tile.sub_graphs.push((pic_coverage_rect, surface_info.clone()));
}
}
// For backdrop-filter, we need to check if any of the dirty rects
// in tiles that are affected by the filter primitive are dirty.
self.deferred_dirty_tests.push(DeferredDirtyTest {
tile_rect: TileRect::new(p0, p1),
prim_rect: pic_coverage_rect,
});
}
}
PrimitiveInstanceKind::LineDecoration { .. } |
PrimitiveInstanceKind::NormalBorder { .. } |
PrimitiveInstanceKind::TextRun { .. } => {
// These don't contribute dependencies
}
};
// Calculate the screen rect in local space. When we calculate backdrops, we
// care only that they cover the visible rect, and don't have any overlapping
// prims in the visible rect.
let visible_local_rect = self.local_rect.intersection(&self.screen_rect_in_pic_space).unwrap_or_default();
if pic_coverage_rect.intersects(&visible_local_rect) {
self.found_prims_after_backdrop = true;
}
// If this primitive considers itself a backdrop candidate, apply further
// checks to see if it matches all conditions to be a backdrop.
let mut vis_flags = PrimitiveVisibilityFlags::empty();
let sub_slice = &mut self.sub_slices[sub_slice_index];
if let Some(mut backdrop_candidate) = backdrop_candidate {
// Update whether the surface that this primitive exists on
// can be considered opaque. Any backdrop kind other than
// a clear primitive (e.g. color, gradient, image) can be
// considered.
match backdrop_candidate.kind {
Some(BackdropKind::Color { .. }) | None => {
let surface = &mut surfaces[prim_surface_index.0];
let is_same_coord_system = frame_context.spatial_tree.is_matching_coord_system(
prim_spatial_node_index,
surface.surface_spatial_node_index,
);
// To be an opaque backdrop, it must:
// - Be the same coordinate system (axis-aligned)
// - Have no clip mask
// - Have a rect that covers the surface local rect
if is_same_coord_system &&
!prim_clip_chain.needs_mask &&
prim_clip_chain.pic_coverage_rect.contains_box(&surface.unclipped_local_rect)
{
// Note that we use `prim_clip_chain.pic_clip_rect` here rather
// than `backdrop_candidate.opaque_rect`. The former is in the
// local space of the surface, the latter is in the local space
// of the top level tile-cache.
surface.is_opaque = true;
}
}
Some(BackdropKind::Clear) => {}
}
let is_suitable_backdrop = match backdrop_candidate.kind {
Some(BackdropKind::Clear) => {
// Clear prims are special - they always end up in their own slice,
// and always set the backdrop. In future, we hope to completely
// remove clear prims, since they don't integrate with the compositing
// system cleanly.
true
}
Some(BackdropKind::Color { .. }) | None => {
// Check a number of conditions to see if we can consider this
// primitive as an opaque backdrop rect. Several of these are conservative
// checks and could be relaxed in future. However, these checks
// are quick and capture the common cases of background rects and images.
// Specifically, we currently require:
// - The primitive is on the main picture cache surface.
// - Same coord system as picture cache (ensures rects are axis-aligned).
// - No clip masks exist.
let same_coord_system = frame_context.spatial_tree.is_matching_coord_system(
prim_spatial_node_index,
self.spatial_node_index,
);
same_coord_system && on_picture_surface
}
};
if sub_slice_index == 0 &&
is_suitable_backdrop &&
sub_slice.compositor_surfaces.is_empty() {
// If the backdrop candidate has a clip-mask, try to extract an opaque inner
// rect that is safe to use for subpixel rendering
if prim_clip_chain.needs_mask {
backdrop_candidate.opaque_rect = clip_store
.get_inner_rect_for_clip_chain(
prim_clip_chain,
&data_stores.clip,
frame_context.spatial_tree,
)
.unwrap_or(PictureRect::zero());
}
// We set the backdrop opaque_rect here, indicating the coverage area, which
// is useful for calculate_subpixel_mode. We will only set the backdrop kind
// if it covers the visible rect.
if backdrop_candidate.opaque_rect.contains_box(&self.backdrop.opaque_rect) {
self.backdrop.opaque_rect = backdrop_candidate.opaque_rect;
}
if let Some(kind) = backdrop_candidate.kind {
if backdrop_candidate.opaque_rect.contains_box(&visible_local_rect) {
self.found_prims_after_backdrop = false;
self.backdrop.kind = Some(kind);
self.backdrop.backdrop_rect = backdrop_candidate.opaque_rect;
// If we have a color backdrop that spans the entire local rect, mark
// the visibility flags of the primitive so it is skipped during batching
// (and also clears any previous primitives). Additionally, update our
// background color to match the backdrop color, which will ensure that
// our tiles are cleared to this color.
if let BackdropKind::Color { color } = kind {
if backdrop_candidate.opaque_rect.contains_box(&self.local_rect) {
vis_flags |= PrimitiveVisibilityFlags::IS_BACKDROP;
self.backdrop.spanning_opaque_color = Some(color);
}
}
}
}
}
}
// Record any new spatial nodes in the used list.
for spatial_node_index in &prim_info.spatial_nodes {
self.spatial_node_comparer.register_used_transform(
*spatial_node_index,
self.frame_id,
frame_context.spatial_tree,
);
}
// Normalize the tile coordinates before adding to tile dependencies.
// For each affected tile, mark any of the primitive dependencies.
for y in p0.y .. p1.y {
for x in p0.x .. p1.x {
// TODO(gw): Convert to 2d array temporarily to avoid hash lookups per-tile?
let key = TileOffset::new(x, y);
let tile = sub_slice.tiles.get_mut(&key).expect("bug: no tile");
tile.add_prim_dependency(&prim_info);
}
}
prim_instance.vis.state = VisibilityState::Visible {
vis_flags,
sub_slice_index: SubSliceIndex::new(sub_slice_index),
};
}
/// Print debug information about this picture cache to a tree printer.
fn print(&self) {
// TODO(gw): This initial implementation is very basic - just printing
// the picture cache state to stdout. In future, we can
// make this dump each frame to a file, and produce a report
// stating which frames had invalidations. This will allow
// diff'ing the invalidation states in a visual tool.
let mut pt = PrintTree::new("Picture Cache");
pt.new_level(format!("Slice {:?}", self.slice));
pt.add_item(format!("background_color: {:?}", self.background_color));
for (sub_slice_index, sub_slice) in self.sub_slices.iter().enumerate() {
pt.new_level(format!("SubSlice {:?}", sub_slice_index));
for y in self.tile_bounds_p0.y .. self.tile_bounds_p1.y {
for x in self.tile_bounds_p0.x .. self.tile_bounds_p1.x {
let key = TileOffset::new(x, y);
let tile = &sub_slice.tiles[&key];
tile.print(&mut pt);
}
}
pt.end_level();
}
pt.end_level();
}
fn calculate_subpixel_mode(&self) -> SubpixelMode {
// We can only consider the full opaque cases if there's no underlays
if self.underlays.is_empty() {
let has_opaque_bg_color = self.background_color.map_or(false, |c| c.a >= 1.0);
// If the overall tile cache is known opaque, subpixel AA is allowed everywhere
if has_opaque_bg_color {
return SubpixelMode::Allow;
}
// If the opaque backdrop rect covers the entire tile cache surface,
// we can allow subpixel AA anywhere, skipping the per-text-run tests
// later on during primitive preparation.
if self.backdrop.opaque_rect.contains_box(&self.local_rect) {
return SubpixelMode::Allow;
}
}
// If we didn't find any valid opaque backdrop, no subpixel AA allowed
if self.backdrop.opaque_rect.is_empty() {
return SubpixelMode::Deny;
}
// Calculate a prohibited rect where we won't allow subpixel AA.
// TODO(gw): This is conservative - it will disallow subpixel AA if there
// are two underlay surfaces with text placed in between them. That's
// probably unlikely to be an issue in practice, but maybe we should support
// an array of prohibted rects?
let prohibited_rect = self
.underlays
.iter()
.fold(
PictureRect::zero(),
|acc, underlay| {
acc.union(&underlay.local_rect)
}
);
// If none of the simple cases above match, we need test where we can support subpixel AA.
// TODO(gw): In future, it may make sense to have > 1 inclusion rect,
// but this handles the common cases.
// TODO(gw): If a text run gets animated such that it's moving in a way that is
// sometimes intersecting with the video rect, this can result in subpixel
// AA flicking on/off for that text run. It's probably very rare, but
// something we should handle in future.
SubpixelMode::Conditional {
allowed_rect: self.backdrop.opaque_rect,
prohibited_rect,
}
}
/// Apply any updates after prim dependency updates. This applies
/// any late tile invalidations, and sets up the dirty rect and
/// set of tile blits.
pub fn post_update(
&mut self,
frame_context: &FrameVisibilityContext,
frame_state: &mut FrameVisibilityState,
) {
assert!(self.current_surface_traversal_depth == 0);
self.dirty_region.reset(self.spatial_node_index);
self.subpixel_mode = self.calculate_subpixel_mode();
self.transform_index = frame_state.composite_state.register_transform(
self.local_to_surface,
// TODO(gw): Once we support scaling of picture cache tiles during compositing,
// that transform gets plugged in here!
self.surface_to_device,
);
let map_pic_to_world = SpaceMapper::new_with_target(
frame_context.root_spatial_node_index,
self.spatial_node_index,
frame_context.global_screen_world_rect,
frame_context.spatial_tree,
);
// A simple GC of the native external surface cache, to remove and free any
// surfaces that were not referenced during the update_prim_dependencies pass.
self.external_native_surface_cache.retain(|_, surface| {
if !surface.used_this_frame {
// If we removed an external surface, we need to mark the dirty rects as
// invalid so a full composite occurs on the next frame.
frame_state.composite_state.dirty_rects_are_valid = false;
frame_state.resource_cache.destroy_compositor_surface(surface.native_surface_id);
}
surface.used_this_frame
});
let pic_to_world_mapper = SpaceMapper::new_with_target(
frame_context.root_spatial_node_index,
self.spatial_node_index,
frame_context.global_screen_world_rect,
frame_context.spatial_tree,
);
let ctx = TileUpdateDirtyContext {
pic_to_world_mapper,
global_device_pixel_scale: frame_context.global_device_pixel_scale,
opacity_bindings: &self.opacity_bindings,
color_bindings: &self.color_bindings,
local_rect: self.local_rect,
invalidate_all: self.invalidate_all_tiles,
};
let mut state = TileUpdateDirtyState {
resource_cache: frame_state.resource_cache,
composite_state: frame_state.composite_state,
compare_cache: &mut self.compare_cache,
spatial_node_comparer: &mut self.spatial_node_comparer,
};
// Step through each tile and invalidate if the dependencies have changed. Determine
// the current opacity setting and whether it's changed.
for sub_slice in &mut self.sub_slices {
for tile in sub_slice.tiles.values_mut() {
tile.update_dirty_and_valid_rects(&ctx, &mut state, frame_context);
}
}
// Process any deferred dirty checks
for sub_slice in &mut self.sub_slices {
for dirty_test in self.deferred_dirty_tests.drain(..) {
// Calculate the total dirty rect from all tiles that this primitive affects
let mut total_dirty_rect = PictureRect::zero();
for y in dirty_test.tile_rect.min.y .. dirty_test.tile_rect.max.y {
for x in dirty_test.tile_rect.min.x .. dirty_test.tile_rect.max.x {
let key = TileOffset::new(x, y);
let tile = sub_slice.tiles.get_mut(&key).expect("bug: no tile");
total_dirty_rect = total_dirty_rect.union(&tile.local_dirty_rect);
}
}
// If that dirty rect intersects with the local rect of the primitive
// being checked, invalidate that region in all of the affected tiles.
// TODO(gw): This is somewhat conservative, we could be more clever
// here and avoid invalidating every tile when this changes.
// We could also store the dirty rect only when the prim
// is encountered, so that we don't invalidate if something
// *after* the query in the rendering order affects invalidation.
if total_dirty_rect.intersects(&dirty_test.prim_rect) {
for y in dirty_test.tile_rect.min.y .. dirty_test.tile_rect.max.y {
for x in dirty_test.tile_rect.min.x .. dirty_test.tile_rect.max.x {
let key = TileOffset::new(x, y);
let tile = sub_slice.tiles.get_mut(&key).expect("bug: no tile");
tile.invalidate(
Some(dirty_test.prim_rect),
InvalidationReason::SurfaceContentChanged,
);
}
}
}
}
}
let mut ctx = TilePostUpdateContext {
local_clip_rect: self.local_clip_rect,
backdrop: None,
current_tile_size: self.current_tile_size,
z_id: ZBufferId::invalid(),
underlays: &self.underlays,
};
let mut state = TilePostUpdateState {
resource_cache: frame_state.resource_cache,
composite_state: frame_state.composite_state,
};
for (i, sub_slice) in self.sub_slices.iter_mut().enumerate().rev() {
// The backdrop is only relevant for the first sub-slice
if i == 0 {
ctx.backdrop = Some(self.backdrop);
}
for compositor_surface in sub_slice.compositor_surfaces.iter_mut().rev() {
compositor_surface.descriptor.z_id = state.composite_state.z_generator.next();
}
ctx.z_id = state.composite_state.z_generator.next();
for tile in sub_slice.tiles.values_mut() {
tile.post_update(&ctx, &mut state, frame_context);
}
}
// Assign z-order for each underlay
for underlay in self.underlays.iter_mut().rev() {
underlay.z_id = state.composite_state.z_generator.next();
}
// Register any opaque external compositor surfaces as potential occluders. This
// is especially useful when viewing video in full-screen mode, as it is
// able to occlude every background tile (avoiding allocation, rasterizion
// and compositing).
// Register any underlays as occluders where possible
for underlay in &self.underlays {
if let Some(world_surface_rect) = underlay.get_occluder_rect(
&self.local_clip_rect,
&map_pic_to_world,
) {
frame_state.composite_state.register_occluder(
underlay.z_id,
world_surface_rect,
);
}
}
for sub_slice in &self.sub_slices {
for compositor_surface in &sub_slice.compositor_surfaces {
if compositor_surface.is_opaque {
if let Some(world_surface_rect) = compositor_surface.descriptor.get_occluder_rect(
&self.local_clip_rect,
&map_pic_to_world,
) {
frame_state.composite_state.register_occluder(
compositor_surface.descriptor.z_id,
world_surface_rect,
);
}
}
}
}
// Register the opaque region of this tile cache as an occluder, which
// is used later in the frame to occlude other tiles.
if !self.backdrop.opaque_rect.is_empty() {
let z_id_backdrop = frame_state.composite_state.z_generator.next();
let backdrop_rect = self.backdrop.opaque_rect
.intersection(&self.local_rect)
.and_then(|r| {
r.intersection(&self.local_clip_rect)
});
if let Some(backdrop_rect) = backdrop_rect {
let world_backdrop_rect = map_pic_to_world
.map(&backdrop_rect)
.expect("bug: unable to map backdrop to world space");
// Since we register the entire backdrop rect, use the opaque z-id for the
// picture cache slice.
frame_state.composite_state.register_occluder(
z_id_backdrop,
world_backdrop_rect,
);
}
}
}
}
pub struct PictureScratchBuffer {
surface_stack: Vec<SurfaceIndex>,
}
impl Default for PictureScratchBuffer {
fn default() -> Self {
PictureScratchBuffer {
surface_stack: Vec::new(),
}
}
}
impl PictureScratchBuffer {
pub fn begin_frame(&mut self) {
self.surface_stack.clear();
}
pub fn recycle(&mut self, recycler: &mut Recycler) {
recycler.recycle_vec(&mut self.surface_stack);
}
}
#[derive(Debug, Copy, Clone, PartialEq)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct SurfaceIndex(pub usize);
/// Information about an offscreen surface. For now,
/// it contains information about the size and coordinate
/// system of the surface. In the future, it will contain
/// information about the contents of the surface, which
/// will allow surfaces to be cached / retained between
/// frames and display lists.
pub struct SurfaceInfo {
/// A local rect defining the size of this surface, in the
/// coordinate system of the surface itself. This contains
/// the unclipped bounding rect of child primitives.
pub unclipped_local_rect: PictureRect,
/// The local space coverage of child primitives after they are
/// are clipped to their owning clip-chain.
pub clipped_local_rect: PictureRect,
/// If true, we know this surface is completely opaque
pub is_opaque: bool,
/// The (conservative) valid part of this surface rect. Used
/// to reduce the size of render target allocation.
pub clipping_rect: PictureRect,
/// Helper structs for mapping local rects in different
/// coordinate systems into the surface coordinates.
pub map_local_to_surface: SpaceMapper<LayoutPixel, PicturePixel>,
/// Defines the positioning node for the surface itself,
/// and the rasterization root for this surface.
pub raster_spatial_node_index: SpatialNodeIndex,
pub surface_spatial_node_index: SpatialNodeIndex,
/// The device pixel ratio specific to this surface.
pub device_pixel_scale: DevicePixelScale,
/// The scale factors of the surface to world transform.
pub world_scale_factors: (f32, f32),
/// Local scale factors surface to raster transform
pub local_scale: (f32, f32),
/// If true, allow snapping on this and child surfaces
pub allow_snapping: bool,
/// If true, the scissor rect must be set when drawing this surface
pub force_scissor_rect: bool,
}
impl SurfaceInfo {
pub fn new(
surface_spatial_node_index: SpatialNodeIndex,
raster_spatial_node_index: SpatialNodeIndex,
world_rect: WorldRect,
spatial_tree: &SpatialTree,
device_pixel_scale: DevicePixelScale,
world_scale_factors: (f32, f32),
local_scale: (f32, f32),
allow_snapping: bool,
force_scissor_rect: bool,
) -> Self {
let map_surface_to_world = SpaceMapper::new_with_target(
spatial_tree.root_reference_frame_index(),
surface_spatial_node_index,
world_rect,
spatial_tree,
);
let pic_bounds = map_surface_to_world
.unmap(&map_surface_to_world.bounds)
.unwrap_or_else(PictureRect::max_rect);
let map_local_to_surface = SpaceMapper::new(
surface_spatial_node_index,
pic_bounds,
);
SurfaceInfo {
unclipped_local_rect: PictureRect::zero(),
clipped_local_rect: PictureRect::zero(),
is_opaque: false,
clipping_rect: PictureRect::zero(),
map_local_to_surface,
raster_spatial_node_index,
surface_spatial_node_index,
device_pixel_scale,
world_scale_factors,
local_scale,
allow_snapping,
force_scissor_rect,
}
}
/// Clamps the blur radius depending on scale factors.
pub fn clamp_blur_radius(
&self,
x_blur_radius: f32,
y_blur_radius: f32,
) -> (f32, f32) {
// Clamping must occur after scale factors are applied, but scale factors are not applied
// until later on. To clamp the blur radius, we first apply the scale factors and then clamp
// and finally revert the scale factors.
let sx_blur_radius = x_blur_radius * self.local_scale.0;
let sy_blur_radius = y_blur_radius * self.local_scale.1;
let largest_scaled_blur_radius = f32::max(
sx_blur_radius * self.world_scale_factors.0,
sy_blur_radius * self.world_scale_factors.1,
);
if largest_scaled_blur_radius > MAX_BLUR_RADIUS {
let sf = MAX_BLUR_RADIUS / largest_scaled_blur_radius;
(x_blur_radius * sf, y_blur_radius * sf)
} else {
// Return the original blur radius to avoid any rounding errors
(x_blur_radius, y_blur_radius)
}
}
pub fn map_to_device_rect(
&self,
local_rect: &PictureRect,
spatial_tree: &SpatialTree,
) -> DeviceRect {
let raster_rect = if self.raster_spatial_node_index != self.surface_spatial_node_index {
assert_eq!(self.device_pixel_scale.0, 1.0);
let local_to_world = SpaceMapper::new_with_target(
spatial_tree.root_reference_frame_index(),
self.surface_spatial_node_index,
WorldRect::max_rect(),
spatial_tree,
);
local_to_world.map(&local_rect).unwrap()
} else {
local_rect.cast_unit()
};
raster_rect * self.device_pixel_scale
}
/// Clip and transform a local rect to a device rect suitable for allocating
/// a child off-screen surface of this surface (e.g. for clip-masks)
pub fn get_surface_rect(
&self,
local_rect: &PictureRect,
spatial_tree: &SpatialTree,
) -> Option<DeviceIntRect> {
let local_rect = match local_rect.intersection(&self.clipping_rect) {
Some(rect) => rect,
None => return None,
};
let raster_rect = if self.raster_spatial_node_index != self.surface_spatial_node_index {
assert_eq!(self.device_pixel_scale.0, 1.0);
let local_to_world = SpaceMapper::new_with_target(
spatial_tree.root_reference_frame_index(),
self.surface_spatial_node_index,
WorldRect::max_rect(),
spatial_tree,
);
local_to_world.map(&local_rect).unwrap()
} else {
// The content should have been culled out earlier.
assert!(self.device_pixel_scale.0 > 0.0);
local_rect.cast_unit()
};
let surface_rect = (raster_rect * self.device_pixel_scale).round_out().to_i32();
if surface_rect.is_empty() {
// The local_rect computed above may have non-empty size that is very
// close to zero. Due to limited arithmetic precision, the SpaceMapper
// might transform the near-zero-sized rect into a zero-sized one.
return None;
}
Some(surface_rect)
}
}
/// Information from `get_surface_rects` about the allocated size, UV sampling
/// parameters etc for an off-screen surface
#[derive(Debug)]
struct SurfaceAllocInfo {
task_size: DeviceIntSize,
needs_scissor_rect: bool,
clipped: DeviceRect,
unclipped: DeviceRect,
clipped_local: PictureRect,
uv_rect_kind: UvRectKind,
}
#[derive(Debug)]
#[cfg_attr(feature = "capture", derive(Serialize))]
pub struct RasterConfig {
/// How this picture should be composited into
/// the parent surface.
// TODO(gw): We should remove this and just use what is in PicturePrimitive
pub composite_mode: PictureCompositeMode,
/// Index to the surface descriptor for this
/// picture.
pub surface_index: SurfaceIndex,
}
bitflags! {
/// A set of flags describing why a picture may need a backing surface.
#[cfg_attr(feature = "capture", derive(Serialize))]
#[derive(Debug, Copy, PartialEq, Eq, Clone, PartialOrd, Ord, Hash)]
pub struct BlitReason: u32 {
/// Mix-blend-mode on a child that requires isolation.
const ISOLATE = 1;
/// Clip node that _might_ require a surface.
const CLIP = 2;
/// Preserve-3D requires a surface for plane-splitting.
const PRESERVE3D = 4;
/// A backdrop that is reused which requires a surface.
const BACKDROP = 8;
}
}
/// Specifies how this Picture should be composited
/// onto the target it belongs to.
#[allow(dead_code)]
#[derive(Debug, Clone)]
#[cfg_attr(feature = "capture", derive(Serialize))]
pub enum PictureCompositeMode {
/// Apply CSS mix-blend-mode effect.
MixBlend(MixBlendMode),
/// Apply a CSS filter (except component transfer).
Filter(Filter),
/// Apply a component transfer filter.
ComponentTransferFilter(FilterDataHandle),
/// Draw to intermediate surface, copy straight across. This
/// is used for CSS isolation, and plane splitting.
Blit(BlitReason),
/// Used to cache a picture as a series of tiles.
TileCache {
slice_id: SliceId,
},
/// Apply an SVG filter
SvgFilter(Vec<FilterPrimitive>, Vec<SFilterData>),
/// A surface that is used as an input to another primitive
IntermediateSurface,
}
impl PictureCompositeMode {
pub fn get_rect(
&self,
surface: &SurfaceInfo,
sub_rect: Option<LayoutRect>,
) -> LayoutRect {
let surface_rect = match sub_rect {
Some(sub_rect) => sub_rect,
None => surface.clipped_local_rect.cast_unit(),
};
match self {
PictureCompositeMode::Filter(Filter::Blur { width, height, should_inflate }) => {
if *should_inflate {
let (width_factor, height_factor) = surface.clamp_blur_radius(*width, *height);
surface_rect.inflate(
width_factor.ceil() * BLUR_SAMPLE_SCALE,
height_factor.ceil() * BLUR_SAMPLE_SCALE,
)
} else {
surface_rect
}
}
PictureCompositeMode::Filter(Filter::DropShadows(ref shadows)) => {
let mut max_blur_radius = 0.0;
for shadow in shadows {
max_blur_radius = f32::max(max_blur_radius, shadow.blur_radius);
}
let (max_blur_radius_x, max_blur_radius_y) = surface.clamp_blur_radius(
max_blur_radius,
max_blur_radius,
);
let blur_inflation_x = max_blur_radius_x * BLUR_SAMPLE_SCALE;
let blur_inflation_y = max_blur_radius_y * BLUR_SAMPLE_SCALE;
surface_rect.inflate(blur_inflation_x, blur_inflation_y)
}
PictureCompositeMode::SvgFilter(primitives, _) => {
let mut result_rect = surface_rect;
let mut output_rects = Vec::with_capacity(primitives.len());
for (cur_index, primitive) in primitives.iter().enumerate() {
let output_rect = match primitive.kind {
FilterPrimitiveKind::Blur(ref primitive) => {
let input = primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect);
let width_factor = primitive.width.round() * BLUR_SAMPLE_SCALE;
let height_factor = primitive.height.round() * BLUR_SAMPLE_SCALE;
input.inflate(width_factor, height_factor)
}
FilterPrimitiveKind::DropShadow(ref primitive) => {
let inflation_factor = primitive.shadow.blur_radius.ceil() * BLUR_SAMPLE_SCALE;
let input = primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect);
let shadow_rect = input.inflate(inflation_factor, inflation_factor);
input.union(&shadow_rect.translate(primitive.shadow.offset * Scale::new(1.0)))
}
FilterPrimitiveKind::Blend(ref primitive) => {
primitive.input1.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect)
.union(&primitive.input2.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect))
}
FilterPrimitiveKind::Composite(ref primitive) => {
primitive.input1.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect)
.union(&primitive.input2.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect))
}
FilterPrimitiveKind::Identity(ref primitive) =>
primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect),
FilterPrimitiveKind::Opacity(ref primitive) =>
primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect),
FilterPrimitiveKind::ColorMatrix(ref primitive) =>
primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect),
FilterPrimitiveKind::ComponentTransfer(ref primitive) =>
primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect),
FilterPrimitiveKind::Offset(ref primitive) => {
let input_rect = primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect);
input_rect.translate(primitive.offset * Scale::new(1.0))
},
FilterPrimitiveKind::Flood(..) => surface_rect,
};
output_rects.push(output_rect);
result_rect = result_rect.union(&output_rect);
}
result_rect
}
_ => {
surface_rect
}
}
}
pub fn get_coverage(
&self,
surface: &SurfaceInfo,
sub_rect: Option<LayoutRect>,
) -> LayoutRect {
let surface_rect = match sub_rect {
Some(sub_rect) => sub_rect,
None => surface.clipped_local_rect.cast_unit(),
};
match self {
PictureCompositeMode::Filter(Filter::Blur { width, height, should_inflate }) => {
if *should_inflate {
let (width_factor, height_factor) = surface.clamp_blur_radius(*width, *height);
surface_rect.inflate(
width_factor.ceil() * BLUR_SAMPLE_SCALE,
height_factor.ceil() * BLUR_SAMPLE_SCALE,
)
} else {
surface_rect
}
}
PictureCompositeMode::Filter(Filter::DropShadows(ref shadows)) => {
let mut rect = surface_rect;
for shadow in shadows {
let (blur_radius_x, blur_radius_y) = surface.clamp_blur_radius(
shadow.blur_radius,
shadow.blur_radius,
);
let blur_inflation_x = blur_radius_x * BLUR_SAMPLE_SCALE;
let blur_inflation_y = blur_radius_y * BLUR_SAMPLE_SCALE;
let shadow_rect = surface_rect
.translate(shadow.offset)
.inflate(blur_inflation_x, blur_inflation_y);
rect = rect.union(&shadow_rect);
}
rect
}
PictureCompositeMode::SvgFilter(primitives, _) => {
let mut result_rect = surface_rect;
let mut output_rects = Vec::with_capacity(primitives.len());
for (cur_index, primitive) in primitives.iter().enumerate() {
let output_rect = match primitive.kind {
FilterPrimitiveKind::Blur(ref primitive) => {
let input = primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect);
let width_factor = primitive.width.round() * BLUR_SAMPLE_SCALE;
let height_factor = primitive.height.round() * BLUR_SAMPLE_SCALE;
input.inflate(width_factor, height_factor)
}
FilterPrimitiveKind::DropShadow(ref primitive) => {
let inflation_factor = primitive.shadow.blur_radius.ceil() * BLUR_SAMPLE_SCALE;
let input = primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect);
let shadow_rect = input.inflate(inflation_factor, inflation_factor);
input.union(&shadow_rect.translate(primitive.shadow.offset * Scale::new(1.0)))
}
FilterPrimitiveKind::Blend(ref primitive) => {
primitive.input1.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect)
.union(&primitive.input2.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect))
}
FilterPrimitiveKind::Composite(ref primitive) => {
primitive.input1.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect)
.union(&primitive.input2.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect))
}
FilterPrimitiveKind::Identity(ref primitive) =>
primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect),
FilterPrimitiveKind::Opacity(ref primitive) =>
primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect),
FilterPrimitiveKind::ColorMatrix(ref primitive) =>
primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect),
FilterPrimitiveKind::ComponentTransfer(ref primitive) =>
primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect),
FilterPrimitiveKind::Offset(ref primitive) => {
let input_rect = primitive.input.to_index(cur_index).map(|index| output_rects[index]).unwrap_or(surface_rect);
input_rect.translate(primitive.offset * Scale::new(1.0))
},
FilterPrimitiveKind::Flood(..) => surface_rect,
};
output_rects.push(output_rect);
result_rect = result_rect.union(&output_rect);
}
result_rect
}
_ => {
surface_rect
}
}
}
}
/// Enum value describing the place of a picture in a 3D context.
#[derive(Clone, Debug)]
#[cfg_attr(feature = "capture", derive(Serialize))]
pub enum Picture3DContext<C> {
/// The picture is not a part of 3D context sub-hierarchy.
Out,
/// The picture is a part of 3D context.
In {
/// Additional data per child for the case of this a root of 3D hierarchy.
root_data: Option<Vec<C>>,
/// The spatial node index of an "ancestor" element, i.e. one
/// that establishes the transformed element's containing block.
///
/// See CSS spec draft for more details:
ancestor_index: SpatialNodeIndex,
/// Index in the built scene's array of plane splitters.
plane_splitter_index: PlaneSplitterIndex,
},
}
/// Information about a preserve-3D hierarchy child that has been plane-split
/// and ordered according to the view direction.
#[derive(Clone, Debug)]
#[cfg_attr(feature = "capture", derive(Serialize))]
pub struct OrderedPictureChild {
pub anchor: PlaneSplitAnchor,
pub gpu_address: GpuCacheAddress,
}
bitflags! {
/// A set of flags describing why a picture may need a backing surface.
#[cfg_attr(feature = "capture", derive(Serialize))]
#[derive(Debug, Copy, PartialEq, Eq, Clone, PartialOrd, Ord, Hash)]
pub struct ClusterFlags: u32 {
/// Whether this cluster is visible when the position node is a backface.
const IS_BACKFACE_VISIBLE = 1;
/// This flag is set during the first pass picture traversal, depending on whether
/// the cluster is visible or not. It's read during the second pass when primitives
/// consult their owning clusters to see if the primitive itself is visible.
const IS_VISIBLE = 2;
}
}
/// Descriptor for a cluster of primitives. For now, this is quite basic but will be
/// extended to handle more spatial clustering of primitives.
#[cfg_attr(feature = "capture", derive(Serialize))]
pub struct PrimitiveCluster {
/// The positioning node for this cluster.
pub spatial_node_index: SpatialNodeIndex,
/// The bounding rect of the cluster, in the local space of the spatial node.
/// This is used to quickly determine the overall bounding rect for a picture
/// during the first picture traversal, which is needed for local scale
/// determination, and render task size calculations.
bounding_rect: LayoutRect,
/// a part of the cluster that we know to be opaque if any. Does not always
/// describe the entire opaque region, but all content within that rect must
/// be opaque.
pub opaque_rect: LayoutRect,
/// The range of primitive instance indices associated with this cluster.
pub prim_range: Range<usize>,
/// Various flags / state for this cluster.
pub flags: ClusterFlags,
}
impl PrimitiveCluster {
/// Construct a new primitive cluster for a given positioning node.
fn new(
spatial_node_index: SpatialNodeIndex,
flags: ClusterFlags,
first_instance_index: usize,
) -> Self {
PrimitiveCluster {
bounding_rect: LayoutRect::zero(),
opaque_rect: LayoutRect::zero(),
spatial_node_index,
flags,
prim_range: first_instance_index..first_instance_index
}
}
/// Return true if this cluster is compatible with the given params
pub fn is_compatible(
&self,
spatial_node_index: SpatialNodeIndex,
flags: ClusterFlags,
instance_index: usize,
) -> bool {
self.flags == flags &&
self.spatial_node_index == spatial_node_index &&
instance_index == self.prim_range.end
}
pub fn prim_range(&self) -> Range<usize> {
self.prim_range.clone()
}
/// Add a primitive instance to this cluster, at the start or end
fn add_instance(
&mut self,
culling_rect: &LayoutRect,
instance_index: usize,
) {
debug_assert_eq!(instance_index, self.prim_range.end);
self.bounding_rect = self.bounding_rect.union(culling_rect);
self.prim_range.end += 1;
}
}
/// A list of primitive instances that are added to a picture
/// This ensures we can keep a list of primitives that
/// are pictures, for a fast initial traversal of the picture
/// tree without walking the instance list.
#[cfg_attr(feature = "capture", derive(Serialize))]
pub struct PrimitiveList {
/// List of primitives grouped into clusters.
pub clusters: Vec<PrimitiveCluster>,
pub child_pictures: Vec<PictureIndex>,
/// The number of preferred compositor surfaces that were found when
/// adding prims to this list, which would be rendered as overlays
pub overlay_surface_count: usize,
/// If true, we found an opaque compositor surface
pub has_opaque_compositor_surface: bool,
pub needs_scissor_rect: bool,
}
impl PrimitiveList {
/// Construct an empty primitive list. This is
/// just used during the take_context / restore_context
/// borrow check dance, which will be removed as the
/// picture traversal pass is completed.
pub fn empty() -> Self {
PrimitiveList {
clusters: Vec::new(),
child_pictures: Vec::new(),
overlay_surface_count: 0,
needs_scissor_rect: false,
has_opaque_compositor_surface: false,
}
}
pub fn merge(&mut self, other: PrimitiveList) {
self.clusters.extend(other.clusters);
self.child_pictures.extend(other.child_pictures);
self.overlay_surface_count += other.overlay_surface_count;
self.needs_scissor_rect |= other.needs_scissor_rect;
self.has_opaque_compositor_surface |= other.has_opaque_compositor_surface;
}
/// Add a primitive instance to the end of the list
pub fn add_prim(
&mut self,
prim_instance: PrimitiveInstance,
prim_rect: LayoutRect,
spatial_node_index: SpatialNodeIndex,
prim_flags: PrimitiveFlags,
prim_instances: &mut Vec<PrimitiveInstance>,
clip_tree_builder: &ClipTreeBuilder,
) {
let mut flags = ClusterFlags::empty();
// Pictures are always put into a new cluster, to make it faster to
// iterate all pictures in a given primitive list.
match prim_instance.kind {
PrimitiveInstanceKind::Picture { pic_index, .. } => {
self.child_pictures.push(pic_index);
}
PrimitiveInstanceKind::TextRun { .. } => {
self.needs_scissor_rect = true;
}
PrimitiveInstanceKind::YuvImage { .. } => {
// Any YUV image that requests a compositor surface is implicitly opaque
if prim_flags.contains(PrimitiveFlags::PREFER_COMPOSITOR_SURFACE) {
self.has_opaque_compositor_surface = true;
}
}
PrimitiveInstanceKind::Image { .. } => {
// For now, we assume that any image that wants a compositor surface
// is transparent, and uses the existing overlay compositor surface
// infrastructure. In future, we could detect opaque images, however
// it's a little bit of work, as scene building doesn't have access
// to the opacity state of an image key at this point.
if prim_flags.contains(PrimitiveFlags::PREFER_COMPOSITOR_SURFACE) {
self.overlay_surface_count += 1;
}
}
_ => {}
}
if prim_flags.contains(PrimitiveFlags::IS_BACKFACE_VISIBLE) {
flags.insert(ClusterFlags::IS_BACKFACE_VISIBLE);
}
let clip_leaf = clip_tree_builder.get_leaf(prim_instance.clip_leaf_id);
let culling_rect = clip_leaf.local_clip_rect
.intersection(&prim_rect)
.unwrap_or_else(LayoutRect::zero);
let instance_index = prim_instances.len();
prim_instances.push(prim_instance);
if let Some(cluster) = self.clusters.last_mut() {
if cluster.is_compatible(spatial_node_index, flags, instance_index) {
cluster.add_instance(&culling_rect, instance_index);
return;
}
}
// Same idea with clusters, using a different distribution.
let clusters_len = self.clusters.len();
if clusters_len == self.clusters.capacity() {
let next_alloc = match clusters_len {
1 ..= 15 => 16 - clusters_len,
16 ..= 127 => 128 - clusters_len,
_ => clusters_len * 2,
};
self.clusters.reserve(next_alloc);
}
let mut cluster = PrimitiveCluster::new(
spatial_node_index,
flags,
instance_index,
);
cluster.add_instance(&culling_rect, instance_index);
self.clusters.push(cluster);
}
/// Returns true if there are no clusters (and thus primitives)
pub fn is_empty(&self) -> bool {
self.clusters.is_empty()
}
}
bitflags! {
#[cfg_attr(feature = "capture", derive(Serialize))]
/// Flags describing properties for a given PicturePrimitive
#[derive(Debug, Copy, PartialEq, Eq, Clone, PartialOrd, Ord, Hash)]
pub struct PictureFlags : u8 {
/// This picture is a resolve target (doesn't actually render content itself,
/// will have content copied in to it)
const IS_RESOLVE_TARGET = 1 << 0;
/// This picture establishes a sub-graph, which affects how SurfaceBuilder will
/// set up dependencies in the render task graph
const IS_SUB_GRAPH = 1 << 1;
/// If set, this picture should not apply snapping via changing the raster root
const DISABLE_SNAPPING = 1 << 2;
}
}
#[cfg_attr(feature = "capture", derive(Serialize))]
pub struct PicturePrimitive {
/// List of primitives, and associated info for this picture.
pub prim_list: PrimitiveList,
/// If false and transform ends up showing the back of the picture,
/// it will be considered invisible.
pub is_backface_visible: bool,
pub primary_render_task_id: Option<RenderTaskId>,
/// If a mix-blend-mode, contains the render task for
/// the readback of the framebuffer that we use to sample
/// from in the mix-blend-mode shader.
/// For drop-shadow filter, this will store the original
/// picture task which would be rendered on screen after
/// blur pass.
pub secondary_render_task_id: Option<RenderTaskId>,
/// How this picture should be composited.
/// If None, don't composite - just draw directly on parent surface.
pub composite_mode: Option<PictureCompositeMode>,
pub raster_config: Option<RasterConfig>,
pub context_3d: Picture3DContext<OrderedPictureChild>,
// Optional cache handles for storing extra data
// in the GPU cache, depending on the type of
// picture.
pub extra_gpu_data_handles: SmallVec<[GpuCacheHandle; 1]>,
/// The spatial node index of this picture when it is
/// composited into the parent picture.
pub spatial_node_index: SpatialNodeIndex,
/// Store the state of the previous local rect
/// for this picture. We need this in order to know when
/// to invalidate segments / drop-shadow gpu cache handles.
pub prev_local_rect: LayoutRect,
/// If false, this picture needs to (re)build segments
/// if it supports segment rendering. This can occur
/// if the local rect of the picture changes due to
/// transform animation and/or scrolling.
pub segments_are_valid: bool,
/// Set to true if we know for sure the picture is fully opaque.
pub is_opaque: bool,
/// Requested raster space for this picture
pub raster_space: RasterSpace,
/// Flags for this picture primitive
pub flags: PictureFlags,
/// The lowest common ancestor clip of all of the primitives in this
/// picture, to be ignored when clipping those primitives and applied
/// later when compositing the picture.
pub clip_root: Option<ClipNodeId>,
}
impl PicturePrimitive {
pub fn print<T: PrintTreePrinter>(
&self,
pictures: &[Self],
self_index: PictureIndex,
pt: &mut T,
) {
pt.new_level(format!("{:?}", self_index));
pt.add_item(format!("cluster_count: {:?}", self.prim_list.clusters.len()));
pt.add_item(format!("spatial_node_index: {:?}", self.spatial_node_index));
pt.add_item(format!("raster_config: {:?}", self.raster_config));
pt.add_item(format!("composite_mode: {:?}", self.composite_mode));
pt.add_item(format!("flags: {:?}", self.flags));
for child_pic_index in &self.prim_list.child_pictures {
pictures[child_pic_index.0].print(pictures, *child_pic_index, pt);
}
pt.end_level();
}
fn resolve_scene_properties(&mut self, properties: &SceneProperties) {
match self.composite_mode {
Some(PictureCompositeMode::Filter(ref mut filter)) => {
match *filter {
Filter::Opacity(ref binding, ref mut value) => {
*value = properties.resolve_float(binding);
}
_ => {}
}
}
_ => {}
}
}
pub fn is_visible(
&self,
spatial_tree: &SpatialTree,
) -> bool {
if let Some(PictureCompositeMode::Filter(ref filter)) = self.composite_mode {
if !filter.is_visible() {
return false;
}
}
// For out-of-preserve-3d pictures, the backface visibility is determined by
// the local transform only.
// Note: we aren't taking the transform relative to the parent picture,
// since picture tree can be more dense than the corresponding spatial tree.
if !self.is_backface_visible {
if let Picture3DContext::Out = self.context_3d {
match spatial_tree.get_local_visible_face(self.spatial_node_index) {
VisibleFace::Front => {}
VisibleFace::Back => return false,
}
}
}
true
}
pub fn new_image(
composite_mode: Option<PictureCompositeMode>,
context_3d: Picture3DContext<OrderedPictureChild>,
prim_flags: PrimitiveFlags,
prim_list: PrimitiveList,
spatial_node_index: SpatialNodeIndex,
raster_space: RasterSpace,
flags: PictureFlags,
) -> Self {
PicturePrimitive {
prim_list,
primary_render_task_id: None,
secondary_render_task_id: None,
composite_mode,
raster_config: None,
context_3d,
extra_gpu_data_handles: SmallVec::new(),
is_backface_visible: prim_flags.contains(PrimitiveFlags::IS_BACKFACE_VISIBLE),
spatial_node_index,
prev_local_rect: LayoutRect::zero(),
segments_are_valid: false,
is_opaque: false,
raster_space,
flags,
clip_root: None,
}
}
pub fn take_context(
&mut self,
pic_index: PictureIndex,
parent_surface_index: Option<SurfaceIndex>,
parent_subpixel_mode: SubpixelMode,
frame_state: &mut FrameBuildingState,
frame_context: &FrameBuildingContext,
scratch: &mut PrimitiveScratchBuffer,
tile_caches: &mut FastHashMap<SliceId, Box<TileCacheInstance>>,
) -> Option<(PictureContext, PictureState, PrimitiveList)> {
self.primary_render_task_id = None;
self.secondary_render_task_id = None;
if !self.is_visible(frame_context.spatial_tree) {
return None;
}
profile_scope!("take_context");
let surface_index = match self.raster_config {
Some(ref raster_config) => raster_config.surface_index,
None => parent_surface_index.expect("bug: no parent"),
};
let surface_spatial_node_index = frame_state.surfaces[surface_index.0].surface_spatial_node_index;
let map_pic_to_world = SpaceMapper::new_with_target(
frame_context.root_spatial_node_index,
surface_spatial_node_index,
frame_context.global_screen_world_rect,
frame_context.spatial_tree,
);
let pic_bounds = map_pic_to_world
.unmap(&map_pic_to_world.bounds)
.unwrap_or_else(PictureRect::max_rect);
let map_local_to_pic = SpaceMapper::new(
surface_spatial_node_index,
pic_bounds,
);
match self.raster_config {
Some(RasterConfig { surface_index, composite_mode: PictureCompositeMode::TileCache { slice_id }, .. }) => {
let tile_cache = tile_caches.get_mut(&slice_id).unwrap();
let mut debug_info = SliceDebugInfo::new();
let mut surface_render_tasks = FastHashMap::default();
let mut surface_local_dirty_rect = PictureRect::zero();
let device_pixel_scale = frame_state
.surfaces[surface_index.0]
.device_pixel_scale;
let mut at_least_one_tile_visible = false;
// Get the overall world space rect of the picture cache. Used to clip
// the tile rects below for occlusion testing to the relevant area.
let world_clip_rect = map_pic_to_world
.map(&tile_cache.local_clip_rect)
.expect("bug: unable to map clip rect")
.round();
let device_clip_rect = (world_clip_rect * frame_context.global_device_pixel_scale).round();
for (sub_slice_index, sub_slice) in tile_cache.sub_slices.iter_mut().enumerate() {
for tile in sub_slice.tiles.values_mut() {
if tile.is_visible {
// Get the world space rect that this tile will actually occupy on screen
let world_draw_rect = world_clip_rect.intersection(&tile.world_valid_rect);
// If that draw rect is occluded by some set of tiles in front of it,
// then mark it as not visible and skip drawing. When it's not occluded
// it will fail this test, and get rasterized by the render task setup
// code below.
match world_draw_rect {
Some(world_draw_rect) => {
// Only check for occlusion on visible tiles that are fixed position.
if tile_cache.spatial_node_index == frame_context.root_spatial_node_index &&
frame_state.composite_state.occluders.is_tile_occluded(tile.z_id, world_draw_rect) {
// If this tile has an allocated native surface, free it, since it's completely
// occluded. We will need to re-allocate this surface if it becomes visible,
// but that's likely to be rare (e.g. when there is no content display list
// for a frame or two during a tab switch).
let surface = tile.surface.as_mut().expect("no tile surface set!");
if let TileSurface::Texture { descriptor: SurfaceTextureDescriptor::Native { id, .. }, .. } = surface {
if let Some(id) = id.take() {
frame_state.resource_cache.destroy_compositor_tile(id);
}
}
tile.is_visible = false;
if frame_context.fb_config.testing {
debug_info.tiles.insert(
tile.tile_offset,
TileDebugInfo::Occluded,
);
}
continue;
}
}
None => {
tile.is_visible = false;
}
}
}
// If we get here, we want to ensure that the surface remains valid in the texture
// cache, _even if_ it's not visible due to clipping or being scrolled off-screen.
// This ensures that we retain valid tiles that are off-screen, but still in the
// display port of this tile cache instance.
if let Some(TileSurface::Texture { descriptor, .. }) = tile.surface.as_ref() {
if let SurfaceTextureDescriptor::TextureCache { handle: Some(handle), .. } = descriptor {
frame_state.resource_cache
.picture_textures.request(handle, frame_state.gpu_cache);
}
}
// If the tile has been found to be off-screen / clipped, skip any further processing.
if !tile.is_visible {
if frame_context.fb_config.testing {
debug_info.tiles.insert(
tile.tile_offset,
TileDebugInfo::Culled,
);
}
continue;
}
at_least_one_tile_visible = true;
if frame_context.debug_flags.contains(DebugFlags::PICTURE_CACHING_DBG) {
tile.root.draw_debug_rects(
&map_pic_to_world,
tile.is_opaque,
tile.current_descriptor.local_valid_rect,
scratch,
frame_context.global_device_pixel_scale,
);
let label_offset = DeviceVector2D::new(
20.0 + sub_slice_index as f32 * 20.0,
30.0 + sub_slice_index as f32 * 20.0,
);
let tile_device_rect = tile.world_tile_rect * frame_context.global_device_pixel_scale;
if tile_device_rect.height() >= label_offset.y {
let surface = tile.surface.as_ref().expect("no tile surface set!");
scratch.push_debug_string(
tile_device_rect.min + label_offset,
debug_colors::RED,
format!("{:?}: s={} is_opaque={} surface={} sub={}",
tile.id,
tile_cache.slice,
tile.is_opaque,
surface.kind(),
sub_slice_index,
),
);
}
}
if let TileSurface::Texture { descriptor, .. } = tile.surface.as_mut().unwrap() {
match descriptor {
SurfaceTextureDescriptor::TextureCache { ref handle, .. } => {
let exists = handle.as_ref().map_or(false,
|handle| frame_state.resource_cache.picture_textures.entry_exists(handle)
);
// Invalidate if the backing texture was evicted.
if exists {
// Request the backing texture so it won't get evicted this frame.
// We specifically want to mark the tile texture as used, even
// if it's detected not visible below and skipped. This is because
// we maintain the set of tiles we care about based on visibility
// during pre_update. If a tile still exists after that, we are
// assuming that it's either visible or we want to retain it for
// a while in case it gets scrolled back onto screen soon.
// TODO(gw): Consider switching to manual eviction policy?
frame_state.resource_cache
.picture_textures
.request(handle.as_ref().unwrap(), frame_state.gpu_cache);
} else {
// If the texture was evicted on a previous frame, we need to assume
// that the entire tile rect is dirty.
tile.invalidate(None, InvalidationReason::NoTexture);
}
}
SurfaceTextureDescriptor::Native { id, .. } => {
if id.is_none() {
// There is no current surface allocation, so ensure the entire tile is invalidated
tile.invalidate(None, InvalidationReason::NoSurface);
}
}
}
}
// Ensure that the dirty rect doesn't extend outside the local valid rect.
tile.local_dirty_rect = tile.local_dirty_rect
.intersection(&tile.current_descriptor.local_valid_rect)
.unwrap_or_else(PictureRect::zero);
surface_local_dirty_rect = surface_local_dirty_rect.union(&tile.local_dirty_rect);
// Update the world/device dirty rect
let world_dirty_rect = map_pic_to_world.map(&tile.local_dirty_rect).expect("bug");
let device_rect = (tile.world_tile_rect * frame_context.global_device_pixel_scale).round();
tile.device_dirty_rect = (world_dirty_rect * frame_context.global_device_pixel_scale)
.round_out()
.intersection(&device_rect)
.unwrap_or_else(DeviceRect::zero);
if tile.is_valid {
if frame_context.fb_config.testing {
debug_info.tiles.insert(
tile.tile_offset,
TileDebugInfo::Valid,
);
}
} else {
// Add this dirty rect to the dirty region tracker. This must be done outside the if statement below,
// so that we include in the dirty region tiles that are handled by a background color only (no
// surface allocation).
tile_cache.dirty_region.add_dirty_region(
tile.local_dirty_rect,
frame_context.spatial_tree,
);
// Ensure that this texture is allocated.
if let TileSurface::Texture { ref mut descriptor } = tile.surface.as_mut().unwrap() {
match descriptor {
SurfaceTextureDescriptor::TextureCache { ref mut handle } => {
frame_state.resource_cache.picture_textures.update(
tile_cache.current_tile_size,
handle,
frame_state.gpu_cache,
&mut frame_state.resource_cache.texture_cache.next_id,
&mut frame_state.resource_cache.texture_cache.pending_updates,
);
}
SurfaceTextureDescriptor::Native { id } => {
if id.is_none() {
// Allocate a native surface id if we're in native compositing mode,
// and we don't have a surface yet (due to first frame, or destruction
// due to tile size changing etc).
if sub_slice.native_surface.is_none() {
let opaque = frame_state
.resource_cache
.create_compositor_surface(
tile_cache.virtual_offset,
tile_cache.current_tile_size,
true,
);
let alpha = frame_state
.resource_cache
.create_compositor_surface(
tile_cache.virtual_offset,
tile_cache.current_tile_size,
false,
);
sub_slice.native_surface = Some(NativeSurface {
opaque,
alpha,
});
}
// Create the tile identifier and allocate it.
let surface_id = if tile.is_opaque {
sub_slice.native_surface.as_ref().unwrap().opaque
} else {
sub_slice.native_surface.as_ref().unwrap().alpha
};
let tile_id = NativeTileId {
surface_id,
x: tile.tile_offset.x,
y: tile.tile_offset.y,
};
frame_state.resource_cache.create_compositor_tile(tile_id);
*id = Some(tile_id);
}
}
}
// The cast_unit() here is because the `content_origin` is expected to be in
// device pixels, however we're establishing raster roots for picture cache
// tiles meaning the `content_origin` needs to be in the local space of that root.
// TODO(gw): `content_origin` should actually be in RasterPixels to be consistent
// with both local / screen raster modes, but this involves a lot of
// changes to render task and picture code.
let content_origin_f = tile.local_tile_rect.min.cast_unit() * device_pixel_scale;
let content_origin = content_origin_f.round();
// TODO: these asserts used to have a threshold of 0.01 but failed intermittently the
// gfx/layers/apz/test/mochitest/test_group_double_tap_zoom-2.html test on android.
// moving the rectangles in space mapping conversion code to the Box2D representaton
// made the failure happen more often.
debug_assert!((content_origin_f.x - content_origin.x).abs() < 0.15);
debug_assert!((content_origin_f.y - content_origin.y).abs() < 0.15);
let surface = descriptor.resolve(
frame_state.resource_cache,
tile_cache.current_tile_size,
);
let scissor_rect = frame_state.composite_state.get_surface_rect(
&tile.local_dirty_rect,
&tile.local_tile_rect,
tile_cache.transform_index,
).to_i32();
let valid_rect = frame_state.composite_state.get_surface_rect(
&tile.current_descriptor.local_valid_rect,
&tile.local_tile_rect,
tile_cache.transform_index,
).to_i32();
let composite_task_size = tile_cache.current_tile_size;
let tile_key = TileKey {
sub_slice_index: SubSliceIndex::new(sub_slice_index),
tile_offset: tile.tile_offset,
};
let mut clear_color = ColorF::TRANSPARENT;
if SubSliceIndex::new(sub_slice_index).is_primary() {
if let Some(background_color) = tile_cache.background_color {
clear_color = background_color;
}
// If this picture cache has a spanning_opaque_color, we will use
// that as the clear color. The primitive that was detected as a
// spanning primitive will have been set with IS_BACKDROP, causing
// it to be skipped and removing everything added prior to it
// during batching.
if let Some(color) = tile_cache.backdrop.spanning_opaque_color {
clear_color = color;
}
}
let cmd_buffer_index = frame_state.cmd_buffers.create_cmd_buffer();
// TODO(gw): As a performance optimization, we could skip the resolve picture
// if the dirty rect is the same as the resolve rect (probably quite
// common for effects that scroll underneath a backdrop-filter, for example).
let use_tile_composite = !tile.sub_graphs.is_empty();
if use_tile_composite {
let mut local_content_rect = tile.local_dirty_rect;
for (sub_graph_rect, surface_stack) in &tile.sub_graphs {
if let Some(dirty_sub_graph_rect) = sub_graph_rect.intersection(&tile.local_dirty_rect) {
for (composite_mode, surface_index) in surface_stack {
let surface = &frame_state.surfaces[surface_index.0];
let rect = composite_mode.get_coverage(
surface,
Some(dirty_sub_graph_rect.cast_unit()),
).cast_unit();
local_content_rect = local_content_rect.union(&rect);
}
}
}
// We know that we'll never need to sample > 300 device pixels outside the tile
// for blurring, so clamp the content rect here so that we don't try to allocate
// a really large surface in the case of a drop-shadow with large offset.
let max_content_rect = (tile.local_dirty_rect.cast_unit() * device_pixel_scale)
.inflate(
MAX_BLUR_RADIUS * BLUR_SAMPLE_SCALE,
MAX_BLUR_RADIUS * BLUR_SAMPLE_SCALE,
)
.round_out()
.to_i32();
let content_device_rect = (local_content_rect.cast_unit() * device_pixel_scale)
.round_out()
.to_i32();
let content_device_rect = content_device_rect
.intersection(&max_content_rect)
.expect("bug: no intersection with tile dirty rect: {content_device_rect:?} / {max_content_rect:?}");
let content_task_size = content_device_rect.size();
let normalized_content_rect = content_task_size.into();
let inner_offset = content_origin + scissor_rect.min.to_vector().to_f32();
let outer_offset = content_device_rect.min.to_f32();
let sub_rect_offset = (inner_offset - outer_offset).round().to_i32();
let render_task_id = frame_state.rg_builder.add().init(
RenderTask::new_dynamic(
content_task_size,
RenderTaskKind::new_picture(
content_task_size,
true,
content_device_rect.min.to_f32(),
surface_spatial_node_index,
// raster == surface implicitly for picture cache tiles
surface_spatial_node_index,
device_pixel_scale,
Some(normalized_content_rect),
None,
Some(clear_color),
cmd_buffer_index,
false,
)
),
);
let composite_task_id = frame_state.rg_builder.add().init(
RenderTask::new(
RenderTaskLocation::Static {
surface: StaticRenderTaskSurface::PictureCache {
surface,
},
rect: composite_task_size.into(),
},
RenderTaskKind::new_tile_composite(
sub_rect_offset,
scissor_rect,
valid_rect,
clear_color,
),
),
);
surface_render_tasks.insert(
tile_key,
SurfaceTileDescriptor {
current_task_id: render_task_id,
composite_task_id: Some(composite_task_id),
dirty_rect: tile.local_dirty_rect,
},
);
} else {
let render_task_id = frame_state.rg_builder.add().init(
RenderTask::new(
RenderTaskLocation::Static {
surface: StaticRenderTaskSurface::PictureCache {
surface,
},
rect: composite_task_size.into(),
},
RenderTaskKind::new_picture(
composite_task_size,
true,
content_origin,
surface_spatial_node_index,
// raster == surface implicitly for picture cache tiles
surface_spatial_node_index,
device_pixel_scale,
Some(scissor_rect),
Some(valid_rect),
Some(clear_color),
cmd_buffer_index,
false,
)
),
);
surface_render_tasks.insert(
tile_key,
SurfaceTileDescriptor {
current_task_id: render_task_id,
composite_task_id: None,
dirty_rect: tile.local_dirty_rect,
},
);
}
}
if frame_context.fb_config.testing {
debug_info.tiles.insert(
tile.tile_offset,
TileDebugInfo::Dirty(DirtyTileDebugInfo {
local_valid_rect: tile.current_descriptor.local_valid_rect,
local_dirty_rect: tile.local_dirty_rect,
}),
);
}
}
let surface = tile.surface.as_ref().expect("no tile surface set!");
let descriptor = CompositeTileDescriptor {
surface_kind: surface.into(),
tile_id: tile.id,
};
let (surface, is_opaque) = match surface {
TileSurface::Color { color } => {
(CompositeTileSurface::Color { color: *color }, true)
}
TileSurface::Clear => {
// Clear tiles are rendered with blend mode pre-multiply-dest-out.
(CompositeTileSurface::Clear, false)
}
TileSurface::Texture { descriptor, .. } => {
let surface = descriptor.resolve(frame_state.resource_cache, tile_cache.current_tile_size);
(
CompositeTileSurface::Texture { surface },
tile.is_opaque
)
}
};
if is_opaque {
sub_slice.opaque_tile_descriptors.push(descriptor);
} else {
sub_slice.alpha_tile_descriptors.push(descriptor);
}
let composite_tile = CompositeTile {
kind: tile_kind(&surface, is_opaque),
surface,
local_rect: tile.local_tile_rect,
local_valid_rect: tile.current_descriptor.local_valid_rect,
local_dirty_rect: tile.local_dirty_rect,
device_clip_rect,
z_id: tile.z_id,
transform_index: tile_cache.transform_index,
};
sub_slice.composite_tiles.push(composite_tile);
// Now that the tile is valid, reset the dirty rect.
tile.local_dirty_rect = PictureRect::zero();
tile.is_valid = true;
}
// Sort the tile descriptor lists, since iterating values in the tile_cache.tiles
// hashmap doesn't provide any ordering guarantees, but we want to detect the
// composite descriptor as equal if the tiles list is the same, regardless of
// ordering.
sub_slice.opaque_tile_descriptors.sort_by_key(|desc| desc.tile_id);
sub_slice.alpha_tile_descriptors.sort_by_key(|desc| desc.tile_id);
}
// Check to see if we should add backdrops as native surfaces.
let backdrop_rect = tile_cache.backdrop.backdrop_rect
.intersection(&tile_cache.local_rect)
.and_then(|r| {
r.intersection(&tile_cache.local_clip_rect)
});
let mut backdrop_in_use_and_visible = false;
if let Some(backdrop_rect) = backdrop_rect {
let supports_surface_for_backdrop = match frame_state.composite_state.compositor_kind {
CompositorKind::Draw { .. } => {
false
}
CompositorKind::Native { capabilities, .. } => {
capabilities.supports_surface_for_backdrop
}
};
if supports_surface_for_backdrop && !tile_cache.found_prims_after_backdrop && at_least_one_tile_visible {
if let Some(BackdropKind::Color { color }) = tile_cache.backdrop.kind {
backdrop_in_use_and_visible = true;
// We're going to let the compositor handle the backdrop as a native surface.
// Hide all of our sub_slice tiles so they aren't also trying to draw it.
for sub_slice in &mut tile_cache.sub_slices {
for tile in sub_slice.tiles.values_mut() {
tile.is_visible = false;
}
}
// Destroy our backdrop surface if it doesn't match the new color.
// TODO: This is a performance hit for animated color backdrops.
if let Some(backdrop_surface) = &tile_cache.backdrop_surface {
if backdrop_surface.color != color {
frame_state.resource_cache.destroy_compositor_surface(backdrop_surface.id);
tile_cache.backdrop_surface = None;
}
}
// Calculate the device_rect for the backdrop, which is just the backdrop_rect
// converted into world space and scaled to device pixels.
let world_backdrop_rect = map_pic_to_world.map(&backdrop_rect).expect("bug: unable to map backdrop rect");
let device_rect = (world_backdrop_rect * frame_context.global_device_pixel_scale).round();
// If we already have a backdrop surface, update the device rect. Otherwise, create
// a backdrop surface.
if let Some(backdrop_surface) = &mut tile_cache.backdrop_surface {
backdrop_surface.device_rect = device_rect;
} else {
// Create native compositor surface with color for the backdrop and store the id.
tile_cache.backdrop_surface = Some(BackdropSurface {
id: frame_state.resource_cache.create_compositor_backdrop_surface(color),
color,
device_rect,
});
}
}
}
}
if !backdrop_in_use_and_visible {
if let Some(backdrop_surface) = &tile_cache.backdrop_surface {
// We've already allocated a backdrop surface, but we're not using it.
// Tell the compositor to get rid of it.
frame_state.resource_cache.destroy_compositor_surface(backdrop_surface.id);
tile_cache.backdrop_surface = None;
}
}
// If invalidation debugging is enabled, dump the picture cache state to a tree printer.
if frame_context.debug_flags.contains(DebugFlags::INVALIDATION_DBG) {
tile_cache.print();
}
// If testing mode is enabled, write some information about the current state
// of this picture cache (made available in RenderResults).
if frame_context.fb_config.testing {
frame_state.composite_state
.picture_cache_debug
.slices
.insert(
tile_cache.slice,
debug_info,
);
}
let descriptor = SurfaceDescriptor::new_tiled(surface_render_tasks);
frame_state.surface_builder.push_surface(
surface_index,
false,
surface_local_dirty_rect,
descriptor,
frame_state.surfaces,
frame_state.rg_builder,
);
}
Some(ref mut raster_config) => {
let (pic_rect, force_scissor_rect) = {
let surface = &frame_state.surfaces[raster_config.surface_index.0];
(surface.clipped_local_rect, surface.force_scissor_rect)
};
let parent_surface_index = parent_surface_index.expect("bug: no parent for child surface");
// Layout space for the picture is picture space from the
// perspective of its child primitives.
let local_rect = pic_rect * Scale::new(1.0);
// If the precise rect changed since last frame, we need to invalidate
// any segments and gpu cache handles for drop-shadows.
// TODO(gw): Requiring storage of the `prev_precise_local_rect` here
// is a total hack. It's required because `prev_precise_local_rect`
// gets written to twice (during initial vis pass and also during
// prepare pass). The proper longer term fix for this is to make
// use of the conservative picture rect for segmenting (which should
// be done during scene building).
if local_rect != self.prev_local_rect {
match raster_config.composite_mode {
PictureCompositeMode::Filter(Filter::DropShadows(..)) => {
for handle in &self.extra_gpu_data_handles {
frame_state.gpu_cache.invalidate(handle);
}
}
_ => {}
}
// Invalidate any segments built for this picture, since the local
// rect has changed.
self.segments_are_valid = false;
self.prev_local_rect = local_rect;
}
let max_surface_size = frame_context
.fb_config
.max_surface_override
.unwrap_or(MAX_SURFACE_SIZE) as f32;
let surface_rects = match get_surface_rects(
raster_config.surface_index,
&raster_config.composite_mode,
parent_surface_index,
&mut frame_state.surfaces,
frame_context.spatial_tree,
max_surface_size,
force_scissor_rect,
) {
Some(rects) => rects,
None => return None,
};
let (raster_spatial_node_index, device_pixel_scale) = {
let surface = &frame_state.surfaces[surface_index.0];
(surface.raster_spatial_node_index, surface.device_pixel_scale)
};
let can_use_shared_surface = !self.flags.contains(PictureFlags::IS_RESOLVE_TARGET);
let primary_render_task_id;
let surface_descriptor;
match raster_config.composite_mode {
PictureCompositeMode::TileCache { .. } => {
unreachable!("handled above");
}
PictureCompositeMode::Filter(Filter::Blur { width, height, .. }) => {
let surface = &frame_state.surfaces[raster_config.surface_index.0];
let (width, height) = surface.clamp_blur_radius(width, height);
let width_std_deviation = width * surface.local_scale.0 * device_pixel_scale.0;
let height_std_deviation = height * surface.local_scale.1 * device_pixel_scale.0;
let blur_std_deviation = DeviceSize::new(
width_std_deviation,
height_std_deviation,
);
let original_size = surface_rects.clipped.size();
// Adjust the size to avoid introducing sampling errors during the down-scaling passes.
// what would be even better is to rasterize the picture at the down-scaled size
// directly.
let adjusted_size = BlurTask::adjusted_blur_source_size(
original_size,
blur_std_deviation,
);
let cmd_buffer_index = frame_state.cmd_buffers.create_cmd_buffer();
// Since we (may have) adjusted the render task size for downscaling accuracy
// above, recalculate the uv rect for tasks that may sample from this blur output
let uv_rect_kind = calculate_uv_rect_kind(
DeviceRect::from_origin_and_size(surface_rects.clipped.min, adjusted_size.to_f32()),
surface_rects.unclipped,
);
let picture_task_id = frame_state.rg_builder.add().init(
RenderTask::new_dynamic(
adjusted_size,
RenderTaskKind::new_picture(
adjusted_size,
surface_rects.needs_scissor_rect,
surface_rects.clipped.min,
surface_spatial_node_index,
raster_spatial_node_index,
device_pixel_scale,
None,
None,
None,
cmd_buffer_index,
can_use_shared_surface,
)
).with_uv_rect_kind(uv_rect_kind)
);
let blur_render_task_id = RenderTask::new_blur(
blur_std_deviation,
picture_task_id,
frame_state.rg_builder,
RenderTargetKind::Color,
None,
original_size.to_i32(),
);
primary_render_task_id = blur_render_task_id;
surface_descriptor = SurfaceDescriptor::new_chained(
picture_task_id,
blur_render_task_id,
surface_rects.clipped_local,
);
}
PictureCompositeMode::Filter(Filter::DropShadows(ref shadows)) => {
let surface = &frame_state.surfaces[raster_config.surface_index.0];
let device_rect = surface_rects.clipped;
let cmd_buffer_index = frame_state.cmd_buffers.create_cmd_buffer();
let picture_task_id = frame_state.rg_builder.add().init(
RenderTask::new_dynamic(
surface_rects.task_size,
RenderTaskKind::new_picture(
surface_rects.task_size,
surface_rects.needs_scissor_rect,
device_rect.min,
surface_spatial_node_index,
raster_spatial_node_index,
device_pixel_scale,
None,
None,
None,
cmd_buffer_index,
can_use_shared_surface,
),
).with_uv_rect_kind(surface_rects.uv_rect_kind)
);
let mut blur_tasks = BlurTaskCache::default();
self.extra_gpu_data_handles.resize(shadows.len(), GpuCacheHandle::new());
let mut blur_render_task_id = picture_task_id;
for shadow in shadows {
let (blur_radius_x, blur_radius_y) = surface.clamp_blur_radius(
shadow.blur_radius,
shadow.blur_radius,
);
blur_render_task_id = RenderTask::new_blur(
DeviceSize::new(
blur_radius_x * surface.local_scale.0 * device_pixel_scale.0,
blur_radius_y * surface.local_scale.1 * device_pixel_scale.0,
),
picture_task_id,
frame_state.rg_builder,
RenderTargetKind::Color,
Some(&mut blur_tasks),
device_rect.size().to_i32(),
);
}
// Add this content picture as a dependency of the parent surface, to
// ensure it isn't free'd after the shadow uses it as an input.
frame_state.surface_builder.add_picture_render_task(picture_task_id);
primary_render_task_id = blur_render_task_id;
self.secondary_render_task_id = Some(picture_task_id);
surface_descriptor = SurfaceDescriptor::new_chained(
picture_task_id,
blur_render_task_id,
surface_rects.clipped_local,
);
}
PictureCompositeMode::MixBlend(mode) if BlendMode::from_mix_blend_mode(
mode,
frame_context.fb_config.gpu_supports_advanced_blend,
frame_context.fb_config.advanced_blend_is_coherent,
frame_context.fb_config.dual_source_blending_is_supported,
).is_none() => {
let parent_surface = &frame_state.surfaces[parent_surface_index.0];
// Create a space mapper that will allow mapping from the local rect
// of the mix-blend primitive into the space of the surface that we
// need to read back from. Note that we use the parent's raster spatial
// node here, so that we are in the correct device space of the parent
// surface, whether it establishes a raster root or not.
let map_pic_to_parent = SpaceMapper::new_with_target(
parent_surface.surface_spatial_node_index,
surface_spatial_node_index,
parent_surface.clipping_rect,
frame_context.spatial_tree,
);
let pic_in_raster_space = map_pic_to_parent
.map(&pic_rect)
.expect("bug: unable to map mix-blend content into parent");
// Apply device pixel ratio for parent surface to get into device
// pixels for that surface.
let backdrop_rect = pic_in_raster_space;
let parent_surface_rect = parent_surface.clipping_rect;
// If there is no available parent surface to read back from (for example, if
// the parent surface is affected by a clip that doesn't affect the child
// surface), then create a dummy 16x16 readback. In future, we could alter
// the composite mode of this primitive to skip the mix-blend, but for simplicity
// we just create a dummy readback for now.
let readback_task_id = match backdrop_rect.intersection(&parent_surface_rect) {
Some(available_rect) => {
// Calculate the UV coords necessary for the shader to sampler
// from the primitive rect within the readback region. This is
// 0..1 for aligned surfaces, but doing it this way allows
// accurate sampling if the primitive bounds have fractional values.
let backdrop_rect = parent_surface.map_to_device_rect(
&backdrop_rect,
frame_context.spatial_tree,
);
let available_rect = parent_surface.map_to_device_rect(
&available_rect,
frame_context.spatial_tree,
).round_out();
let backdrop_uv = calculate_uv_rect_kind(
available_rect,
backdrop_rect,
);
frame_state.rg_builder.add().init(
RenderTask::new_dynamic(
available_rect.size().to_i32(),
RenderTaskKind::new_readback(Some(available_rect.min)),
).with_uv_rect_kind(backdrop_uv)
)
}
None => {
frame_state.rg_builder.add().init(
RenderTask::new_dynamic(
DeviceIntSize::new(16, 16),
RenderTaskKind::new_readback(None),
)
)
}
};
frame_state.surface_builder.add_child_render_task(
readback_task_id,
frame_state.rg_builder,
);
self.secondary_render_task_id = Some(readback_task_id);
let task_size = surface_rects.clipped.size().to_i32();
let cmd_buffer_index = frame_state.cmd_buffers.create_cmd_buffer();
let render_task_id = frame_state.rg_builder.add().init(
RenderTask::new_dynamic(
task_size,
RenderTaskKind::new_picture(
task_size,
surface_rects.needs_scissor_rect,
surface_rects.clipped.min,
surface_spatial_node_index,
raster_spatial_node_index,
device_pixel_scale,
None,
None,
None,
cmd_buffer_index,
can_use_shared_surface,
)
).with_uv_rect_kind(surface_rects.uv_rect_kind)
);
primary_render_task_id = render_task_id;
surface_descriptor = SurfaceDescriptor::new_simple(
render_task_id,
surface_rects.clipped_local,
);
}
PictureCompositeMode::Filter(..) => {
let cmd_buffer_index = frame_state.cmd_buffers.create_cmd_buffer();
let render_task_id = frame_state.rg_builder.add().init(
RenderTask::new_dynamic(
surface_rects.task_size,
RenderTaskKind::new_picture(
surface_rects.task_size,
surface_rects.needs_scissor_rect,
surface_rects.clipped.min,
surface_spatial_node_index,
raster_spatial_node_index,
device_pixel_scale,
None,
None,
None,
cmd_buffer_index,
can_use_shared_surface,
)
).with_uv_rect_kind(surface_rects.uv_rect_kind)
);
primary_render_task_id = render_task_id;
surface_descriptor = SurfaceDescriptor::new_simple(
render_task_id,
surface_rects.clipped_local,
);
}
PictureCompositeMode::ComponentTransferFilter(..) => {
let cmd_buffer_index = frame_state.cmd_buffers.create_cmd_buffer();
let render_task_id = frame_state.rg_builder.add().init(
RenderTask::new_dynamic(
surface_rects.task_size,
RenderTaskKind::new_picture(
surface_rects.task_size,
surface_rects.needs_scissor_rect,
surface_rects.clipped.min,
surface_spatial_node_index,
raster_spatial_node_index,
device_pixel_scale,
None,
None,
None,
cmd_buffer_index,
can_use_shared_surface,
)
).with_uv_rect_kind(surface_rects.uv_rect_kind)
);
primary_render_task_id = render_task_id;
surface_descriptor = SurfaceDescriptor::new_simple(
render_task_id,
surface_rects.clipped_local,
);
}
PictureCompositeMode::MixBlend(..) |
PictureCompositeMode::Blit(_) => {
let cmd_buffer_index = frame_state.cmd_buffers.create_cmd_buffer();
let render_task_id = frame_state.rg_builder.add().init(
RenderTask::new_dynamic(
surface_rects.task_size,
RenderTaskKind::new_picture(
surface_rects.task_size,
surface_rects.needs_scissor_rect,
surface_rects.clipped.min,
surface_spatial_node_index,
raster_spatial_node_index,
device_pixel_scale,
None,
None,
None,
cmd_buffer_index,
can_use_shared_surface,
)
).with_uv_rect_kind(surface_rects.uv_rect_kind)
);
primary_render_task_id = render_task_id;
surface_descriptor = SurfaceDescriptor::new_simple(
render_task_id,
surface_rects.clipped_local,
);
}
PictureCompositeMode::IntermediateSurface => {
if !scratch.required_sub_graphs.contains(&pic_index) {
return None;
}
// TODO(gw): Remove all the mostly duplicated code in each of these
// match cases (they used to be quite different).
let cmd_buffer_index = frame_state.cmd_buffers.create_cmd_buffer();
let render_task_id = frame_state.rg_builder.add().init(
RenderTask::new_dynamic(
surface_rects.task_size,
RenderTaskKind::new_picture(
surface_rects.task_size,
surface_rects.needs_scissor_rect,
surface_rects.clipped.min,
surface_spatial_node_index,
raster_spatial_node_index,
device_pixel_scale,
None,
None,
None,
cmd_buffer_index,
can_use_shared_surface,
)
).with_uv_rect_kind(surface_rects.uv_rect_kind)
);
primary_render_task_id = render_task_id;
surface_descriptor = SurfaceDescriptor::new_simple(
render_task_id,
surface_rects.clipped_local,
);
}
PictureCompositeMode::SvgFilter(ref primitives, ref filter_datas) => {
let cmd_buffer_index = frame_state.cmd_buffers.create_cmd_buffer();
let picture_task_id = frame_state.rg_builder.add().init(
RenderTask::new_dynamic(
surface_rects.task_size,
RenderTaskKind::new_picture(
surface_rects.task_size,
surface_rects.needs_scissor_rect,
surface_rects.clipped.min,
surface_spatial_node_index,
raster_spatial_node_index,
device_pixel_scale,
None,
None,
None,
cmd_buffer_index,
can_use_shared_surface,
)
).with_uv_rect_kind(surface_rects.uv_rect_kind)
);
let filter_task_id = RenderTask::new_svg_filter(
primitives,
filter_datas,
frame_state.rg_builder,
surface_rects.clipped.size().to_i32(),
surface_rects.uv_rect_kind,
picture_task_id,
device_pixel_scale,
);
primary_render_task_id = filter_task_id;
surface_descriptor = SurfaceDescriptor::new_chained(
picture_task_id,
filter_task_id,
surface_rects.clipped_local,
);
}
}
let is_sub_graph = self.flags.contains(PictureFlags::IS_SUB_GRAPH);
frame_state.surface_builder.push_surface(
raster_config.surface_index,
is_sub_graph,
surface_rects.clipped_local,
surface_descriptor,
frame_state.surfaces,
frame_state.rg_builder,
);
self.primary_render_task_id = Some(primary_render_task_id);
}
None => {}
};
let state = PictureState {
map_local_to_pic,
map_pic_to_world,
};
let mut dirty_region_count = 0;
// If this is a picture cache, push the dirty region to ensure any
// child primitives are culled and clipped to the dirty rect(s).
if let Some(RasterConfig { composite_mode: PictureCompositeMode::TileCache { slice_id }, .. }) = self.raster_config {
let dirty_region = tile_caches[&slice_id].dirty_region.clone();
frame_state.push_dirty_region(dirty_region);
dirty_region_count += 1;
}
// Disallow subpixel AA if an intermediate surface is needed.
// TODO(lsalzman): allow overriding parent if intermediate surface is opaque
let subpixel_mode = match self.raster_config {
Some(RasterConfig { ref composite_mode, .. }) => {
let subpixel_mode = match composite_mode {
PictureCompositeMode::TileCache { slice_id } => {
tile_caches[&slice_id].subpixel_mode
}
PictureCompositeMode::Blit(..) |
PictureCompositeMode::ComponentTransferFilter(..) |
PictureCompositeMode::Filter(..) |
PictureCompositeMode::MixBlend(..) |
PictureCompositeMode::IntermediateSurface |
PictureCompositeMode::SvgFilter(..) => {
// TODO(gw): We can take advantage of the same logic that
// exists in the opaque rect detection for tile
// caches, to allow subpixel text on other surfaces
// that can be detected as opaque.
SubpixelMode::Deny
}
};
subpixel_mode
}
None => {
SubpixelMode::Allow
}
};
// Still disable subpixel AA if parent forbids it
let subpixel_mode = match (parent_subpixel_mode, subpixel_mode) {
(SubpixelMode::Allow, SubpixelMode::Allow) => {
// Both parent and this surface unconditionally allow subpixel AA
SubpixelMode::Allow
}
(SubpixelMode::Allow, SubpixelMode::Conditional { allowed_rect, prohibited_rect }) => {
// Parent allows, but we are conditional subpixel AA
SubpixelMode::Conditional {
allowed_rect,
prohibited_rect,
}
}
(SubpixelMode::Conditional { allowed_rect, prohibited_rect }, SubpixelMode::Allow) => {
// Propagate conditional subpixel mode to child pictures that allow subpixel AA
SubpixelMode::Conditional {
allowed_rect,
prohibited_rect,
}
}
(SubpixelMode::Conditional { .. }, SubpixelMode::Conditional { ..}) => {
unreachable!("bug: only top level picture caches have conditional subpixel");
}
(SubpixelMode::Deny, _) | (_, SubpixelMode::Deny) => {
// Either parent or this surface explicitly deny subpixel, these take precedence
SubpixelMode::Deny
}
};
let context = PictureContext {
pic_index,
raster_spatial_node_index: frame_state.surfaces[surface_index.0].raster_spatial_node_index,
surface_spatial_node_index,
surface_index,
dirty_region_count,
subpixel_mode,
};
let prim_list = mem::replace(&mut self.prim_list, PrimitiveList::empty());
Some((context, state, prim_list))
}
pub fn restore_context(
&mut self,
pic_index: PictureIndex,
prim_list: PrimitiveList,
context: PictureContext,
prim_instances: &[PrimitiveInstance],
frame_context: &FrameBuildingContext,
frame_state: &mut FrameBuildingState,
) {
// Pop any dirty regions this picture set
for _ in 0 .. context.dirty_region_count {
frame_state.pop_dirty_region();
}
if self.raster_config.is_some() {
frame_state.surface_builder.pop_surface(
pic_index,
frame_state.rg_builder,
frame_state.cmd_buffers,
);
}
if let Picture3DContext::In { root_data: Some(ref mut list), plane_splitter_index, .. } = self.context_3d {
let splitter = &mut frame_state.plane_splitters[plane_splitter_index.0];
// Resolve split planes via BSP
PicturePrimitive::resolve_split_planes(
splitter,
list,
&mut frame_state.gpu_cache,
&frame_context.spatial_tree,
);
// Add the child prims to the relevant command buffers
let mut cmd_buffer_targets = Vec::new();
for child in list {
let child_prim_instance = &prim_instances[child.anchor.instance_index.0 as usize];
if frame_state.surface_builder.get_cmd_buffer_targets_for_prim(
&child_prim_instance.vis,
&mut cmd_buffer_targets,
) {
let prim_cmd = PrimitiveCommand::complex(
child.anchor.instance_index,
child.gpu_address
);
frame_state.push_prim(
&prim_cmd,
child.anchor.spatial_node_index,
&cmd_buffer_targets,
);
}
}
}
self.prim_list = prim_list;
}
/// Add a primitive instance to the plane splitter. The function would generate
/// an appropriate polygon, clip it against the frustum, and register with the
/// given plane splitter.
pub fn add_split_plane(
splitter: &mut PlaneSplitter,
spatial_tree: &SpatialTree,
prim_spatial_node_index: SpatialNodeIndex,
original_local_rect: LayoutRect,
combined_local_clip_rect: &LayoutRect,
world_rect: WorldRect,
plane_split_anchor: PlaneSplitAnchor,
) -> bool {
let transform = spatial_tree
.get_world_transform(prim_spatial_node_index);
let matrix = transform.clone().into_transform().cast().to_untyped();
// Apply the local clip rect here, before splitting. This is
// because the local clip rect can't be applied in the vertex
// shader for split composites, since we are drawing polygons
// rather that rectangles. The interpolation still works correctly
// since we determine the UVs by doing a bilerp with a factor
// from the original local rect.
let local_rect = match original_local_rect
.intersection(combined_local_clip_rect)
{
Some(rect) => rect.cast(),
None => return false,
};
let world_rect = world_rect.cast();
match transform {
CoordinateSpaceMapping::Local => {
let polygon = Polygon::from_rect(
local_rect.to_rect() * Scale::new(1.0),
plane_split_anchor,
);
splitter.add(polygon);
}
CoordinateSpaceMapping::ScaleOffset(scale_offset) if scale_offset.scale == Vector2D::new(1.0, 1.0) => {
let inv_matrix = scale_offset.inverse().to_transform().cast();
let polygon = Polygon::from_transformed_rect_with_inverse(
local_rect.to_rect().to_untyped(),
&matrix,
&inv_matrix,
plane_split_anchor,
).unwrap();
splitter.add(polygon);
}
CoordinateSpaceMapping::ScaleOffset(_) |
CoordinateSpaceMapping::Transform(_) => {
let mut clipper = Clipper::new();
let results = clipper.clip_transformed(
Polygon::from_rect(
local_rect.to_rect().to_untyped(),
plane_split_anchor,
),
&matrix,
Some(world_rect.to_rect().to_untyped()),
);
if let Ok(results) = results {
for poly in results {
splitter.add(poly);
}
}
}
}
true
}
fn resolve_split_planes(
splitter: &mut PlaneSplitter,
ordered: &mut Vec<OrderedPictureChild>,
gpu_cache: &mut GpuCache,
spatial_tree: &SpatialTree,
) {
ordered.clear();
// Process the accumulated split planes and order them for rendering.
// Z axis is directed at the screen, `sort` is ascending, and we need back-to-front order.
let sorted = splitter.sort(vec3(0.0, 0.0, 1.0));
ordered.reserve(sorted.len());
for poly in sorted {
let transform = match spatial_tree
.get_world_transform(poly.anchor.spatial_node_index)
.inverse()
{
Some(transform) => transform.into_transform(),
// logging this would be a bit too verbose
None => continue,
};
let local_points = [
transform.transform_point3d(poly.points[0].cast_unit().to_f32()),
transform.transform_point3d(poly.points[1].cast_unit().to_f32()),
transform.transform_point3d(poly.points[2].cast_unit().to_f32()),
transform.transform_point3d(poly.points[3].cast_unit().to_f32()),
];
// If any of the points are un-transformable, just drop this
// plane from drawing.
if local_points.iter().any(|p| p.is_none()) {
continue;
}
let p0 = local_points[0].unwrap();
let p1 = local_points[1].unwrap();
let p2 = local_points[2].unwrap();
let p3 = local_points[3].unwrap();
let gpu_blocks = [
[p0.x, p0.y, p1.x, p1.y].into(),
[p2.x, p2.y, p3.x, p3.y].into(),
];
let gpu_handle = gpu_cache.push_per_frame_blocks(&gpu_blocks);
let gpu_address = gpu_cache.get_address(&gpu_handle);
ordered.push(OrderedPictureChild {
anchor: poly.anchor,
gpu_address,
});
}
}
/// Do initial checks to determine whether this picture should be drawn as part of the
/// frame build.
pub fn pre_update(
&mut self,
frame_context: &FrameBuildingContext,
) {
// Resolve animation properties
self.resolve_scene_properties(frame_context.scene_properties);
}
/// Called during initial picture traversal, before we know the
/// bounding rect of children. It is possible to determine the
/// surface / raster config now though.
pub fn assign_surface(
&mut self,
frame_context: &FrameBuildingContext,
parent_surface_index: Option<SurfaceIndex>,
tile_caches: &mut FastHashMap<SliceId, Box<TileCacheInstance>>,
surfaces: &mut Vec<SurfaceInfo>,
) -> Option<SurfaceIndex> {
// Reset raster config in case we early out below.
self.raster_config = None;
match self.composite_mode {
Some(ref composite_mode) => {
let surface_spatial_node_index = self.spatial_node_index;
// Currently, we ensure that the scaling factor is >= 1.0 as a smaller scale factor can result in blurry output.
let mut min_scale;
let mut max_scale = 1.0e32;
// If a raster root is established, this surface should be scaled based on the scale factors of the surface raster to parent raster transform.
// This scaling helps ensure that the content in this surface does not become blurry or pixelated when composited in the parent surface.
let world_scale_factors = match parent_surface_index {
Some(parent_surface_index) => {
let parent_surface = &surfaces[parent_surface_index.0];
let local_to_surface = frame_context
.spatial_tree
.get_relative_transform(
surface_spatial_node_index,
parent_surface.surface_spatial_node_index,
);
// Since we can't determine reasonable scale factors for transforms
// with perspective, just use a scale of (1,1) for now, which is
// what Gecko does when it choosed to supplies a scale factor anyway.
// In future, we might be able to improve the quality here by taking
// into account the screen rect after clipping, but for now this gives
// better results than just taking the matrix scale factors.
let scale_factors = if local_to_surface.is_perspective() {
(1.0, 1.0)
} else {
local_to_surface.scale_factors()
};
let scale_factors = (
scale_factors.0 * parent_surface.world_scale_factors.0,
scale_factors.1 * parent_surface.world_scale_factors.1,
);
scale_factors
}
None => {
let local_to_surface_scale_factors = frame_context
.spatial_tree
.get_relative_transform(
surface_spatial_node_index,
frame_context.spatial_tree.root_reference_frame_index(),
)
.scale_factors();
let scale_factors = (
local_to_surface_scale_factors.0,
local_to_surface_scale_factors.1,
);
scale_factors
}
};
// TODO(gw): For now, we disable snapping on any sub-graph, as that implies
// that the spatial / raster node must be the same as the parent
// surface. In future, we may be able to support snapping in these
// cases (if it's even useful?) or perhaps add a ENABLE_SNAPPING
// picture flag, if the IS_SUB_GRAPH is ever useful in a different
// context.
let allow_snapping = !self.flags.contains(PictureFlags::DISABLE_SNAPPING);
// For some primitives (e.g. text runs) we can't rely on the bounding rect being
// exactly correct. For these cases, ensure we set a scissor rect when drawing
// this picture to a surface.
// TODO(gw) In future, we may be able to improve how the text run bounding rect is
// calculated so that we don't need to do this. We could either fix Gecko up to
// provide an exact bounds, or we could calculate the bounding rect internally in
// WR, which would be easier to do efficiently once we have retained text runs
// as part of the planned frame-tree interface changes.
let force_scissor_rect = self.prim_list.needs_scissor_rect;
// Check if there is perspective or if an SVG filter is applied, and thus whether a new
// rasterization root should be established.
let (device_pixel_scale, raster_spatial_node_index, local_scale, world_scale_factors) = match composite_mode {
PictureCompositeMode::TileCache { slice_id } => {
let tile_cache = tile_caches.get_mut(&slice_id).unwrap();
// Get the complete scale-offset from local space to device space
let local_to_device = get_relative_scale_offset(
tile_cache.spatial_node_index,
frame_context.root_spatial_node_index,
frame_context.spatial_tree,
);
let local_to_cur_raster_scale = local_to_device.scale.x / tile_cache.current_raster_scale;
// We only update the raster scale if we're in high quality zoom mode, or there is no
// pinch-zoom active, or the zoom has doubled or halved since the raster scale was
// last updated. During a low-quality zoom we therefore typically retain the previous
// scale factor, which avoids expensive re-rasterizations, except for when the zoom
// has become too large or too small when we re-rasterize to avoid bluriness or a
// proliferation of picture cache tiles. When the zoom ends we select a high quality
// scale factor for the next frame to be drawn.
if !frame_context.fb_config.low_quality_pinch_zoom
|| !frame_context
.spatial_tree.get_spatial_node(tile_cache.spatial_node_index)
.is_ancestor_or_self_zooming
|| local_to_cur_raster_scale <= 0.5
|| local_to_cur_raster_scale >= 2.0
{
tile_cache.current_raster_scale = local_to_device.scale.x;
}
// We may need to minify when zooming out picture cache tiles
min_scale = 0.0;
if frame_context.fb_config.low_quality_pinch_zoom {
// Force the scale for this tile cache to be the currently selected
// local raster scale, so we don't need to rasterize tiles during
// the pinch-zoom.
min_scale = tile_cache.current_raster_scale;
max_scale = tile_cache.current_raster_scale;
}
// Pick the largest scale factor of the transform for the scaling factor.
let scaling_factor = world_scale_factors.0.max(world_scale_factors.1).max(min_scale).min(max_scale);
let device_pixel_scale = Scale::new(scaling_factor);
(device_pixel_scale, surface_spatial_node_index, (1.0, 1.0), world_scale_factors)
}
_ => {
let surface_spatial_node = frame_context.spatial_tree.get_spatial_node(surface_spatial_node_index);
let enable_snapping =
allow_snapping &&
surface_spatial_node.coordinate_system_id == CoordinateSystemId::root() &&
surface_spatial_node.snapping_transform.is_some();
if enable_snapping {
let raster_spatial_node_index = frame_context.spatial_tree.root_reference_frame_index();
let local_to_raster_transform = frame_context
.spatial_tree
.get_relative_transform(
self.spatial_node_index,
raster_spatial_node_index,
);
let local_scale = local_to_raster_transform.scale_factors();
(Scale::new(1.0), raster_spatial_node_index, local_scale, (1.0, 1.0))
} else {
// If client supplied a specific local scale, use that instead of
// estimating from parent transform
let world_scale_factors = match self.raster_space {
RasterSpace::Screen => world_scale_factors,
RasterSpace::Local(scale) => (scale, scale),
};
let device_pixel_scale = Scale::new(
world_scale_factors.0.max(world_scale_factors.1).min(max_scale)
);
(device_pixel_scale, surface_spatial_node_index, (1.0, 1.0), world_scale_factors)
}
}
};
let surface = SurfaceInfo::new(
surface_spatial_node_index,
raster_spatial_node_index,
frame_context.global_screen_world_rect,
&frame_context.spatial_tree,
device_pixel_scale,
world_scale_factors,
local_scale,
allow_snapping,
force_scissor_rect,
);
let surface_index = SurfaceIndex(surfaces.len());
surfaces.push(surface);
self.raster_config = Some(RasterConfig {
composite_mode: composite_mode.clone(),
surface_index,
});
Some(surface_index)
}
None => {
None
}
}
}
/// Called after updating child pictures during the initial
/// picture traversal. Bounding rects are propagated from
/// child pictures up to parent picture surfaces, so that the
/// parent bounding rect includes any dynamic picture bounds.
pub fn propagate_bounding_rect(
&mut self,
surface_index: SurfaceIndex,
parent_surface_index: Option<SurfaceIndex>,
surfaces: &mut [SurfaceInfo],
frame_context: &FrameBuildingContext,
) {
let surface = &mut surfaces[surface_index.0];
for cluster in &mut self.prim_list.clusters {
cluster.flags.remove(ClusterFlags::IS_VISIBLE);
// Skip the cluster if backface culled.
if !cluster.flags.contains(ClusterFlags::IS_BACKFACE_VISIBLE) {
// For in-preserve-3d primitives and pictures, the backface visibility is
// evaluated relative to the containing block.
if let Picture3DContext::In { ancestor_index, .. } = self.context_3d {
let mut face = VisibleFace::Front;
frame_context.spatial_tree.get_relative_transform_with_face(
cluster.spatial_node_index,
ancestor_index,
Some(&mut face),
);
if face == VisibleFace::Back {
continue
}
}
}
// No point including this cluster if it can't be transformed
let spatial_node = &frame_context
.spatial_tree
.get_spatial_node(cluster.spatial_node_index);
if !spatial_node.invertible {
continue;
}
// Map the cluster bounding rect into the space of the surface, and
// include it in the surface bounding rect.
surface.map_local_to_surface.set_target_spatial_node(
cluster.spatial_node_index,
frame_context.spatial_tree,
);
// Mark the cluster visible, since it passed the invertible and
// backface checks.
cluster.flags.insert(ClusterFlags::IS_VISIBLE);
if let Some(cluster_rect) = surface.map_local_to_surface.map(&cluster.bounding_rect) {
surface.unclipped_local_rect = surface.unclipped_local_rect.union(&cluster_rect);
}
}
// If this picture establishes a surface, then map the surface bounding
// rect into the parent surface coordinate space, and propagate that up
// to the parent.
if let Some(ref mut raster_config) = self.raster_config {
// Propagate up to parent surface, now that we know this surface's static rect
if let Some(parent_surface_index) = parent_surface_index {
let surface_rect = raster_config.composite_mode.get_coverage(
surface,
Some(surface.unclipped_local_rect.cast_unit()),
);
let parent_surface = &mut surfaces[parent_surface_index.0];
parent_surface.map_local_to_surface.set_target_spatial_node(
self.spatial_node_index,
frame_context.spatial_tree,
);
// Drop shadows draw both a content and shadow rect, so need to expand the local
// rect of any surfaces to be composited in parent surfaces correctly.
if let Some(parent_surface_rect) = parent_surface
.map_local_to_surface
.map(&surface_rect)
{
parent_surface.unclipped_local_rect =
parent_surface.unclipped_local_rect.union(&parent_surface_rect);
}
}
}
}
pub fn prepare_for_render(
&mut self,
frame_state: &mut FrameBuildingState,
data_stores: &mut DataStores,
) -> bool {
let raster_config = match self.raster_config {
Some(ref mut raster_config) => raster_config,
None => {
return true
}
};
// TODO(gw): Almost all of the Picture types below use extra_gpu_cache_data
// to store the same type of data. The exception is the filter
// with a ColorMatrix, which stores the color matrix here. It's
// probably worth tidying this code up to be a bit more consistent.
// Perhaps store the color matrix after the common data, even though
// it's not used by that shader.
match raster_config.composite_mode {
PictureCompositeMode::TileCache { .. } => {}
PictureCompositeMode::Filter(Filter::Blur { .. }) => {}
PictureCompositeMode::Filter(Filter::DropShadows(ref shadows)) => {
self.extra_gpu_data_handles.resize(shadows.len(), GpuCacheHandle::new());
for (shadow, extra_handle) in shadows.iter().zip(self.extra_gpu_data_handles.iter_mut()) {
if let Some(mut request) = frame_state.gpu_cache.request(extra_handle) {
let surface = &frame_state.surfaces[raster_config.surface_index.0];
let prim_rect = surface.clipped_local_rect.cast_unit();
// Basic brush primitive header is (see end of prepare_prim_for_render_inner in prim_store.rs)
// [brush specific data]
// [segment_rect, segment data]
let (blur_inflation_x, blur_inflation_y) = surface.clamp_blur_radius(
shadow.blur_radius,
shadow.blur_radius,
);
let shadow_rect = prim_rect.inflate(
blur_inflation_x * BLUR_SAMPLE_SCALE,
blur_inflation_y * BLUR_SAMPLE_SCALE,
).translate(shadow.offset);
// ImageBrush colors
request.push(shadow.color.premultiplied());
request.push(PremultipliedColorF::WHITE);
request.push([
shadow_rect.width(),
shadow_rect.height(),
0.0,
0.0,
]);
// segment rect / extra data
request.push(shadow_rect);
request.push([0.0, 0.0, 0.0, 0.0]);
}
}
}
PictureCompositeMode::Filter(ref filter) => {
match *filter {
Filter::ColorMatrix(ref m) => {
if self.extra_gpu_data_handles.is_empty() {
self.extra_gpu_data_handles.push(GpuCacheHandle::new());
}
if let Some(mut request) = frame_state.gpu_cache.request(&mut self.extra_gpu_data_handles[0]) {
for i in 0..5 {
request.push([m[i*4], m[i*4+1], m[i*4+2], m[i*4+3]]);
}
}
}
Filter::Flood(ref color) => {
if self.extra_gpu_data_handles.is_empty() {
self.extra_gpu_data_handles.push(GpuCacheHandle::new());
}
if let Some(mut request) = frame_state.gpu_cache.request(&mut self.extra_gpu_data_handles[0]) {
request.push(color.to_array());
}
}
_ => {}
}
}
PictureCompositeMode::ComponentTransferFilter(handle) => {
let filter_data = &mut data_stores.filter_data[handle];
filter_data.update(frame_state);
}
PictureCompositeMode::MixBlend(..) |
PictureCompositeMode::Blit(_) |
PictureCompositeMode::IntermediateSurface |
PictureCompositeMode::SvgFilter(..) => {}
}
true
}
}
fn get_transform_key(
spatial_node_index: SpatialNodeIndex,
cache_spatial_node_index: SpatialNodeIndex,
spatial_tree: &SpatialTree,
) -> TransformKey {
spatial_tree.get_relative_transform(
spatial_node_index,
cache_spatial_node_index,
).into()
}
/// A key for storing primitive comparison results during tile dependency tests.
#[derive(Debug, Copy, Clone, Eq, Hash, PartialEq)]
struct PrimitiveComparisonKey {
prev_index: PrimitiveDependencyIndex,
curr_index: PrimitiveDependencyIndex,
}
/// Information stored an image dependency
#[derive(Debug, Copy, Clone, PartialEq, PeekPoke, Default)]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct ImageDependency {
pub key: ImageKey,
pub generation: ImageGeneration,
}
impl ImageDependency {
pub const INVALID: ImageDependency = ImageDependency {
key: ImageKey::DUMMY,
generation: ImageGeneration::INVALID,
};
}
/// In some cases, we need to know the dirty rect of all tiles in order
/// to correctly invalidate a primitive.
#[derive(Debug)]
struct DeferredDirtyTest {
/// The tile rect that the primitive being checked affects
tile_rect: TileRect,
/// The picture-cache local rect of the primitive being checked
prim_rect: PictureRect,
}
/// A helper struct to compare a primitive and all its sub-dependencies.
struct PrimitiveComparer<'a> {
prev_data: &'a [u8],
curr_data: &'a [u8],
prev_frame_id: FrameId,
curr_frame_id: FrameId,
resource_cache: &'a ResourceCache,
spatial_node_comparer: &'a mut SpatialNodeComparer,
opacity_bindings: &'a FastHashMap<PropertyBindingId, OpacityBindingInfo>,
color_bindings: &'a FastHashMap<PropertyBindingId, ColorBindingInfo>,
}
impl<'a> PrimitiveComparer<'a> {
fn new(
prev: &'a TileDescriptor,
curr: &'a TileDescriptor,
resource_cache: &'a ResourceCache,
spatial_node_comparer: &'a mut SpatialNodeComparer,
opacity_bindings: &'a FastHashMap<PropertyBindingId, OpacityBindingInfo>,
color_bindings: &'a FastHashMap<PropertyBindingId, ColorBindingInfo>,
) -> Self {
PrimitiveComparer {
prev_data: &prev.dep_data,
curr_data: &curr.dep_data,
prev_frame_id: prev.last_updated_frame_id,
curr_frame_id: curr.last_updated_frame_id,
resource_cache,
spatial_node_comparer,
opacity_bindings,
color_bindings,
}
}
/// Check if two primitive descriptors are the same.
fn compare_prim(
&mut self,
prev_desc: &PrimitiveDescriptor,
curr_desc: &PrimitiveDescriptor,
) -> PrimitiveCompareResult {
let resource_cache = self.resource_cache;
let spatial_node_comparer = &mut self.spatial_node_comparer;
let opacity_bindings = self.opacity_bindings;
let color_bindings = self.color_bindings;
// Check equality of the PrimitiveDescriptor
if prev_desc != curr_desc {
return PrimitiveCompareResult::Descriptor;
}
let mut prev_dep_data = &self.prev_data[prev_desc.dep_offset as usize ..];
let mut curr_dep_data = &self.curr_data[curr_desc.dep_offset as usize ..];
let mut prev_dep = PrimitiveDependency::SpatialNode { index: SpatialNodeIndex::INVALID };
let mut curr_dep = PrimitiveDependency::SpatialNode { index: SpatialNodeIndex::INVALID };
debug_assert_eq!(prev_desc.dep_count, curr_desc.dep_count);
for _ in 0 .. prev_desc.dep_count {
prev_dep_data = peek_from_slice(prev_dep_data, &mut prev_dep);
curr_dep_data = peek_from_slice(curr_dep_data, &mut curr_dep);
match (&prev_dep, &curr_dep) {
(PrimitiveDependency::Clip { clip: prev }, PrimitiveDependency::Clip { clip: curr }) => {
if prev != curr {
return PrimitiveCompareResult::Clip;
}
}
(PrimitiveDependency::SpatialNode { index: prev }, PrimitiveDependency::SpatialNode { index: curr }) => {
let prev_key = SpatialNodeKey {
spatial_node_index: *prev,
frame_id: self.prev_frame_id,
};
let curr_key = SpatialNodeKey {
spatial_node_index: *curr,
frame_id: self.curr_frame_id,
};
if !spatial_node_comparer.are_transforms_equivalent(&prev_key, &curr_key) {
return PrimitiveCompareResult::Transform;
}
}
(PrimitiveDependency::OpacityBinding { binding: prev }, PrimitiveDependency::OpacityBinding { binding: curr }) => {
if prev != curr {
return PrimitiveCompareResult::OpacityBinding;
}
if let OpacityBinding::Binding(id) = curr {
if opacity_bindings
.get(id)
.map_or(true, |info| info.changed) {
return PrimitiveCompareResult::OpacityBinding;
}
}
}
(PrimitiveDependency::ColorBinding { binding: prev }, PrimitiveDependency::ColorBinding { binding: curr }) => {
if prev != curr {
return PrimitiveCompareResult::ColorBinding;
}
if let ColorBinding::Binding(id) = curr {
if color_bindings
.get(id)
.map_or(true, |info| info.changed) {
return PrimitiveCompareResult::ColorBinding;
}
}
}
(PrimitiveDependency::Image { image: prev }, PrimitiveDependency::Image { image: curr }) => {
if prev != curr {
return PrimitiveCompareResult::Image;
}
if resource_cache.get_image_generation(curr.key) != curr.generation {
return PrimitiveCompareResult::Image;
}
}
_ => {
// There was a mismatch between types of dependencies, so something changed
return PrimitiveCompareResult::Descriptor;
}
}
}
PrimitiveCompareResult::Equal
}
}
/// Details for a node in a quadtree that tracks dirty rects for a tile.
#[cfg_attr(any(feature="capture",feature="replay"), derive(Clone))]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub enum TileNodeKind {
Leaf {
/// The index buffer of primitives that affected this tile previous frame
#[cfg_attr(any(feature = "capture", feature = "replay"), serde(skip))]
prev_indices: Vec<PrimitiveDependencyIndex>,
/// The index buffer of primitives that affect this tile on this frame
#[cfg_attr(any(feature = "capture", feature = "replay"), serde(skip))]
curr_indices: Vec<PrimitiveDependencyIndex>,
/// A bitset of which of the last 64 frames have been dirty for this leaf.
#[cfg_attr(any(feature = "capture", feature = "replay"), serde(skip))]
dirty_tracker: u64,
/// The number of frames since this node split or merged.
#[cfg_attr(any(feature = "capture", feature = "replay"), serde(skip))]
frames_since_modified: usize,
},
Node {
/// The four children of this node
children: Vec<TileNode>,
},
}
/// The kind of modification that a tile wants to do
#[derive(Copy, Clone, PartialEq, Debug)]
enum TileModification {
Split,
Merge,
}
/// A node in the dirty rect tracking quadtree.
#[cfg_attr(any(feature="capture",feature="replay"), derive(Clone))]
#[cfg_attr(feature = "capture", derive(Serialize))]
#[cfg_attr(feature = "replay", derive(Deserialize))]
pub struct TileNode {
/// Leaf or internal node
pub kind: TileNodeKind,
/// Rect of this node in the same space as the tile cache picture
pub rect: PictureBox2D,
}
impl TileNode {
/// Construct a new leaf node, with the given primitive dependency index buffer
fn new_leaf(curr_indices: Vec<PrimitiveDependencyIndex>) -> Self {
TileNode {
kind: TileNodeKind::Leaf {
prev_indices: Vec::new(),
curr_indices,
dirty_tracker: 0,
frames_since_modified: 0,
},
rect: PictureBox2D::zero(),
}
}
/// Draw debug information about this tile node
fn draw_debug_rects(
&self,
pic_to_world_mapper: &SpaceMapper<PicturePixel, WorldPixel>,
is_opaque: bool,
local_valid_rect: PictureRect,
scratch: &mut PrimitiveScratchBuffer,
global_device_pixel_scale: DevicePixelScale,
) {
match self.kind {
TileNodeKind::Leaf { dirty_tracker, .. } => {
let color = if (dirty_tracker & 1) != 0 {
debug_colors::RED
} else if is_opaque {
debug_colors::GREEN
} else {
debug_colors::YELLOW
};
if let Some(local_rect) = local_valid_rect.intersection(&self.rect) {
let world_rect = pic_to_world_mapper
.map(&local_rect)
.unwrap();
let device_rect = world_rect * global_device_pixel_scale;
let outer_color = color.scale_alpha(0.3);
let inner_color = outer_color.scale_alpha(0.5);
scratch.push_debug_rect(
device_rect.inflate(-3.0, -3.0),
outer_color,
inner_color
);
}
}
TileNodeKind::Node { ref children, .. } => {
for child in children.iter() {
child.draw_debug_rects(
pic_to_world_mapper,
is_opaque,
local_valid_rect,
scratch,
global_device_pixel_scale,
);
}
}
}
}
/// Calculate the four child rects for a given node
fn get_child_rects(
rect: &PictureBox2D,
result: &mut [PictureBox2D; 4],
) {
let p0 = rect.min;
let p1 = rect.max;
let pc = p0 + rect.size() * 0.5;
*result = [
PictureBox2D::new(
p0,
pc,
),
PictureBox2D::new(
PicturePoint::new(pc.x, p0.y),
PicturePoint::new(p1.x, pc.y),
),
PictureBox2D::new(
PicturePoint::new(p0.x, pc.y),
PicturePoint::new(pc.x, p1.y),
),
PictureBox2D::new(
pc,
p1,
),
];
}
/// Called during pre_update, to clear the current dependencies
fn clear(
&mut self,
rect: PictureBox2D,
) {
self.rect = rect;
match self.kind {
TileNodeKind::Leaf { ref mut prev_indices, ref mut curr_indices, ref mut dirty_tracker, ref mut frames_since_modified } => {
// Swap current dependencies to be the previous frame
mem::swap(prev_indices, curr_indices);
curr_indices.clear();
// Note that another frame has passed in the dirty bit trackers
*dirty_tracker = *dirty_tracker << 1;
*frames_since_modified += 1;
}
TileNodeKind::Node { ref mut children, .. } => {
let mut child_rects = [PictureBox2D::zero(); 4];
TileNode::get_child_rects(&rect, &mut child_rects);
assert_eq!(child_rects.len(), children.len());
for (child, rect) in children.iter_mut().zip(child_rects.iter()) {
child.clear(*rect);
}
}
}
}
/// Add a primitive dependency to this node
fn add_prim(
&mut self,
index: PrimitiveDependencyIndex,
prim_rect: &PictureBox2D,
) {
match self.kind {
TileNodeKind::Leaf { ref mut curr_indices, .. } => {
curr_indices.push(index);
}
TileNodeKind::Node { ref mut children, .. } => {
for child in children.iter_mut() {
if child.rect.intersects(prim_rect) {
child.add_prim(index, prim_rect);
}
}
}
}
}
/// Apply a merge or split operation to this tile, if desired
fn maybe_merge_or_split(
&mut self,
level: i32,
curr_prims: &[PrimitiveDescriptor],
max_split_levels: i32,
) {
// Determine if this tile wants to split or merge
let mut tile_mod = None;
fn get_dirty_frames(
dirty_tracker: u64,
frames_since_modified: usize,
) -> Option<u32> {
// Only consider splitting or merging at least 64 frames since we last changed
if frames_since_modified > 64 {
// Each bit in the tracker is a frame that was recently invalidated
Some(dirty_tracker.count_ones())
} else {
None
}
}
match self.kind {
TileNodeKind::Leaf { dirty_tracker, frames_since_modified, .. } => {
// Only consider splitting if the tree isn't too deep.
if level < max_split_levels {
if let Some(dirty_frames) = get_dirty_frames(dirty_tracker, frames_since_modified) {
// If the tile has invalidated > 50% of the recent number of frames, split.
if dirty_frames > 32 {
tile_mod = Some(TileModification::Split);
}
}
}
}
TileNodeKind::Node { ref children, .. } => {
// There's two conditions that cause a node to merge its children:
// (1) If _all_ the child nodes are constantly invalidating, then we are wasting
// CPU time tracking dependencies for each child, so merge them.
// (2) If _none_ of the child nodes are recently invalid, then the page content
// has probably changed, and we no longer need to track fine grained dependencies here.
let mut static_count = 0;
let mut changing_count = 0;
for child in children {
// Only consider merging nodes at the edge of the tree.
if let TileNodeKind::Leaf { dirty_tracker, frames_since_modified, .. } = child.kind {
if let Some(dirty_frames) = get_dirty_frames(dirty_tracker, frames_since_modified) {
if dirty_frames == 0 {
// Hasn't been invalidated for some time
static_count += 1;
} else if dirty_frames == 64 {
// Is constantly being invalidated
changing_count += 1;
}
}
}
// Only merge if all the child tiles are in agreement. Otherwise, we have some
// that are invalidating / static, and it's worthwhile tracking dependencies for
// them individually.
if static_count == 4 || changing_count == 4 {
tile_mod = Some(TileModification::Merge);
}
}
}
}
match tile_mod {
Some(TileModification::Split) => {
// To split a node, take the current dependency index buffer for this node, and
// split it into child index buffers.
let curr_indices = match self.kind {
TileNodeKind::Node { .. } => {
unreachable!("bug - only leaves can split");
}
TileNodeKind::Leaf { ref mut curr_indices, .. } => {
curr_indices.take()
}
};
let mut child_rects = [PictureBox2D::zero(); 4];
TileNode::get_child_rects(&self.rect, &mut child_rects);
let mut child_indices = [
Vec::new(),
Vec::new(),
Vec::new(),
Vec::new(),
];
// Step through the index buffer, and add primitives to each of the children
// that they intersect.
for index in curr_indices {
let prim = &curr_prims[index.0 as usize];
for (child_rect, indices) in child_rects.iter().zip(child_indices.iter_mut()) {
if prim.prim_clip_box.intersects(child_rect) {
indices.push(index);
}
}
}
// Create the child nodes and switch from leaf -> node.
let children = child_indices
.iter_mut()
.map(|i| TileNode::new_leaf(mem::replace(i, Vec::new())))
.collect();
self.kind = TileNodeKind::Node {
children,
};
}
Some(TileModification::Merge) => {
// Construct a merged index buffer by collecting the dependency index buffers
// from each child, and merging them into a de-duplicated index buffer.
let merged_indices = match self.kind {
TileNodeKind::Node { ref mut children, .. } => {
let mut merged_indices = Vec::new();
for child in children.iter() {
let child_indices = match child.kind {
TileNodeKind::Leaf { ref curr_indices, .. } => {
curr_indices
}
TileNodeKind::Node { .. } => {
unreachable!("bug: child is not a leaf");
}
};
merged_indices.extend_from_slice(child_indices);
}
merged_indices.sort();
merged_indices.dedup();
merged_indices
}
TileNodeKind::Leaf { .. } => {
unreachable!("bug - trying to merge a leaf");
}
};
// Switch from a node to a leaf, with the combined index buffer
self.kind = TileNodeKind::Leaf {
prev_indices: Vec::new(),
curr_indices: merged_indices,
dirty_tracker: 0,
frames_since_modified: 0,
};
}
None => {
// If this node didn't merge / split, then recurse into children
// to see if they want to split / merge.
if let TileNodeKind::Node { ref mut children, .. } = self.kind {
for child in children.iter_mut() {
child.maybe_merge_or_split(
level+1,
curr_prims,
max_split_levels,
);
}
}
}
}
}
/// Update the dirty state of this node, building the overall dirty rect
fn update_dirty_rects(
&mut self,
prev_prims: &[PrimitiveDescriptor],
curr_prims: &[PrimitiveDescriptor],
prim_comparer: &mut PrimitiveComparer,
dirty_rect: &mut PictureBox2D,
compare_cache: &mut FastHashMap<PrimitiveComparisonKey, PrimitiveCompareResult>,
invalidation_reason: &mut Option<InvalidationReason>,
frame_context: &FrameVisibilityContext,
) {
match self.kind {
TileNodeKind::Node { ref mut children, .. } => {
for child in children.iter_mut() {
child.update_dirty_rects(
prev_prims,
curr_prims,
prim_comparer,
dirty_rect,
compare_cache,
invalidation_reason,
frame_context,
);
}
}
TileNodeKind::Leaf { ref prev_indices, ref curr_indices, ref mut dirty_tracker, .. } => {
// If the index buffers are of different length, they must be different
if prev_indices.len() == curr_indices.len() {
// Walk each index buffer, comparing primitives
for (prev_index, curr_index) in prev_indices.iter().zip(curr_indices.iter()) {
let i0 = prev_index.0 as usize;
let i1 = curr_index.0 as usize;
// Compare the primitives, caching the result in a hash map
// to save comparisons in other tree nodes.
let key = PrimitiveComparisonKey {
prev_index: *prev_index,
curr_index: *curr_index,
};
let prim_compare_result = *compare_cache
.entry(key)
.or_insert_with(|| {
let prev = &prev_prims[i0];
let curr = &curr_prims[i1];
prim_comparer.compare_prim(prev, curr)
});
// If not the same, mark this node as dirty and update the dirty rect
if prim_compare_result != PrimitiveCompareResult::Equal {
if invalidation_reason.is_none() {
*invalidation_reason = Some(InvalidationReason::Content);
}
*dirty_rect = self.rect.union(dirty_rect);
*dirty_tracker = *dirty_tracker | 1;
break;
}
}
} else {
if invalidation_reason.is_none() {
*invalidation_reason = Some(InvalidationReason::PrimCount);
}
*dirty_rect = self.rect.union(dirty_rect);
*dirty_tracker = *dirty_tracker | 1;
}
}
}
}
}
impl CompositeState {
// A helper function to destroy all native surfaces for a given list of tiles
pub fn destroy_native_tiles<'a, I: Iterator<Item = &'a mut Box<Tile>>>(
&mut self,
tiles_iter: I,
resource_cache: &mut ResourceCache,
) {
// Any old tiles that remain after the loop above are going to be dropped. For
// simple composite mode, the texture cache handle will expire and be collected
// by the texture cache. For native compositor mode, we need to explicitly
// invoke a callback to the client to destroy that surface.
if let CompositorKind::Native { .. } = self.compositor_kind {
for tile in tiles_iter {
// Only destroy native surfaces that have been allocated. It's
// possible for display port tiles to be created that never
// come on screen, and thus never get a native surface allocated.
if let Some(TileSurface::Texture { descriptor: SurfaceTextureDescriptor::Native { ref mut id, .. }, .. }) = tile.surface {
if let Some(id) = id.take() {
resource_cache.destroy_compositor_tile(id);
}
}
}
}
}
}
fn get_relative_scale_offset(
child_spatial_node_index: SpatialNodeIndex,
parent_spatial_node_index: SpatialNodeIndex,
spatial_tree: &SpatialTree,
) -> ScaleOffset {
let transform = spatial_tree.get_relative_transform(
child_spatial_node_index,
parent_spatial_node_index,
);
let mut scale_offset = match transform {
CoordinateSpaceMapping::Local => ScaleOffset::identity(),
CoordinateSpaceMapping::ScaleOffset(scale_offset) => scale_offset,
CoordinateSpaceMapping::Transform(m) => {
ScaleOffset::from_transform(&m).expect("bug: pictures caches don't support complex transforms")
}
};
// Compositors expect things to be aligned on device pixels. Logic at a higher level ensures that is
// true, but floating point inaccuracy can sometimes result in small differences, so remove
// them here.
scale_offset.offset = scale_offset.offset.round();
scale_offset
}
pub fn calculate_screen_uv(
p: DevicePoint,
clipped: DeviceRect,
) -> DeviceHomogeneousVector {
// TODO(gw): Switch to a simple mix, no bilerp / homogeneous vec needed anymore
DeviceHomogeneousVector::new(
(p.x - clipped.min.x) / (clipped.max.x - clipped.min.x),
(p.y - clipped.min.y) / (clipped.max.y - clipped.min.y),
0.0,
1.0,
)
}
fn get_surface_rects(
surface_index: SurfaceIndex,
composite_mode: &PictureCompositeMode,
parent_surface_index: SurfaceIndex,
surfaces: &mut [SurfaceInfo],
spatial_tree: &SpatialTree,
max_surface_size: f32,
force_scissor_rect: bool,
) -> Option<SurfaceAllocInfo> {
let parent_surface = &surfaces[parent_surface_index.0];
let local_to_parent = SpaceMapper::new_with_target(
parent_surface.surface_spatial_node_index,
surfaces[surface_index.0].surface_spatial_node_index,
parent_surface.clipping_rect,
spatial_tree,
);
let local_clip_rect = local_to_parent
.unmap(&parent_surface.clipping_rect)
.unwrap_or(PictureRect::max_rect())
.cast_unit();
let surface = &mut surfaces[surface_index.0];
let (clipped_local, unclipped_local) = match composite_mode {
PictureCompositeMode::Filter(Filter::DropShadows(ref shadows)) => {
let local_prim_rect = surface.clipped_local_rect;
let mut required_local_rect = local_prim_rect
.intersection(&local_clip_rect)
.unwrap_or(PictureRect::zero());
for shadow in shadows {
let (blur_radius_x, blur_radius_y) = surface.clamp_blur_radius(
shadow.blur_radius,
shadow.blur_radius,
);
let blur_inflation_x = blur_radius_x * BLUR_SAMPLE_SCALE;
let blur_inflation_y = blur_radius_y * BLUR_SAMPLE_SCALE;
let local_shadow_rect = local_prim_rect
.translate(shadow.offset.cast_unit())
.inflate(blur_inflation_x, blur_inflation_y);
if let Some(clipped_shadow_rect) = local_clip_rect.intersection(&local_shadow_rect) {
let required_shadow_rect = clipped_shadow_rect.inflate(blur_inflation_x, blur_inflation_y);
let local_clipped_shadow_rect = required_shadow_rect.translate(-shadow.offset.cast_unit());
required_local_rect = required_local_rect.union(&local_clipped_shadow_rect);
}
}
let unclipped = composite_mode.get_rect(surface, None);
let clipped = required_local_rect;
let clipped = match clipped.intersection(&unclipped.cast_unit()) {
Some(rect) => rect,
None => return None,
};
(clipped, unclipped)
}
_ => {
let surface_origin = surface.clipped_local_rect.min.to_vector().cast_unit();
let normalized_prim_rect = composite_mode
.get_rect(surface, None)
.translate(-surface_origin);
let normalized_clip_rect = local_clip_rect
.cast_unit()
.translate(-surface_origin);
let norm_clipped_rect = match normalized_prim_rect.intersection(&normalized_clip_rect) {
Some(rect) => rect,
None => return None,
};
let norm_clipped_rect = composite_mode.get_rect(surface, Some(norm_clipped_rect));
let norm_clipped_rect = match norm_clipped_rect.intersection(&normalized_prim_rect) {
Some(rect) => rect,
None => return None,
};
let unclipped = normalized_prim_rect.translate(surface_origin);
let clipped = norm_clipped_rect.translate(surface_origin);
(clipped.cast_unit(), unclipped.cast_unit())
}
};
let (mut clipped, mut unclipped) = if surface.raster_spatial_node_index != surface.surface_spatial_node_index {
assert_eq!(surface.device_pixel_scale.0, 1.0);
let local_to_world = SpaceMapper::new_with_target(
spatial_tree.root_reference_frame_index(),
surface.surface_spatial_node_index,
WorldRect::max_rect(),
spatial_tree,
);
let clipped = (local_to_world.map(&clipped_local.cast_unit()).unwrap() * surface.device_pixel_scale).round_out();
let unclipped = local_to_world.map(&unclipped_local).unwrap() * surface.device_pixel_scale;
(clipped, unclipped)
} else {
let clipped = (clipped_local.cast_unit() * surface.device_pixel_scale).round_out();
let unclipped = unclipped_local.cast_unit() * surface.device_pixel_scale;
(clipped, unclipped)
};
let task_size_f = clipped.size();
if task_size_f.width > max_surface_size || task_size_f.height > max_surface_size {
let max_dimension = clipped_local.width().max(clipped_local.height()).ceil();
surface.raster_spatial_node_index = surface.surface_spatial_node_index;
surface.device_pixel_scale = Scale::new(max_surface_size / max_dimension);
clipped = (clipped_local.cast_unit() * surface.device_pixel_scale).round();
unclipped = unclipped_local.cast_unit() * surface.device_pixel_scale;
}
let task_size = clipped.size().to_i32();
debug_assert!(task_size.width <= max_surface_size as i32);
debug_assert!(task_size.height <= max_surface_size as i32);
let uv_rect_kind = calculate_uv_rect_kind(
clipped,
unclipped,
);
// If the task size is zero sized, skip creation and drawing of it
if task_size.width == 0 || task_size.height == 0 {
return None;
}
// If the final clipped surface rect is not the same or larger as the unclipped
// local rect of the surface, we need to enable scissor rect (which disables
// merging batches between this and other render tasks allocated to the same
// render target). This is conservative - we could do better in future by
// distinguishing between clips that affect the surface itself vs. clips on
// child primitives that don't affect this.
let needs_scissor_rect = force_scissor_rect || !clipped_local.contains_box(&surface.unclipped_local_rect);
Some(SurfaceAllocInfo {
task_size,
needs_scissor_rect,
clipped,
unclipped,
clipped_local,
uv_rect_kind,
})
}
fn calculate_uv_rect_kind(
clipped: DeviceRect,
unclipped: DeviceRect,
) -> UvRectKind {
let top_left = calculate_screen_uv(
unclipped.top_left().cast_unit(),
clipped,
);
let top_right = calculate_screen_uv(
unclipped.top_right().cast_unit(),
clipped,
);
let bottom_left = calculate_screen_uv(
unclipped.bottom_left().cast_unit(),
clipped,
);
let bottom_right = calculate_screen_uv(
unclipped.bottom_right().cast_unit(),
clipped,
);
UvRectKind::Quad {
top_left,
top_right,
bottom_left,
bottom_right,
}
}
#[test]
fn test_large_surface_scale_1() {
use crate::spatial_tree::{SceneSpatialTree, SpatialTree};
let mut cst = SceneSpatialTree::new();
let root_reference_frame_index = cst.root_reference_frame_index();
let mut spatial_tree = SpatialTree::new();
spatial_tree.apply_updates(cst.end_frame_and_get_pending_updates());
spatial_tree.update_tree(&SceneProperties::new());
let map_local_to_surface = SpaceMapper::new_with_target(
root_reference_frame_index,
root_reference_frame_index,
PictureRect::max_rect(),
&spatial_tree,
);
let mut surfaces = vec![
SurfaceInfo {
unclipped_local_rect: PictureRect::max_rect(),
clipped_local_rect: PictureRect::max_rect(),
is_opaque: true,
clipping_rect: PictureRect::max_rect(),
map_local_to_surface: map_local_to_surface.clone(),
raster_spatial_node_index: root_reference_frame_index,
surface_spatial_node_index: root_reference_frame_index,
device_pixel_scale: DevicePixelScale::new(1.0),
world_scale_factors: (1.0, 1.0),
local_scale: (1.0, 1.0),
allow_snapping: true,
force_scissor_rect: false,
},
SurfaceInfo {
unclipped_local_rect: PictureRect::new(
PicturePoint::new(52.76350021362305, 0.0),
PicturePoint::new(159.6738739013672, 35.0),
),
clipped_local_rect: PictureRect::max_rect(),
is_opaque: true,
clipping_rect: PictureRect::max_rect(),
map_local_to_surface,
raster_spatial_node_index: root_reference_frame_index,
surface_spatial_node_index: root_reference_frame_index,
device_pixel_scale: DevicePixelScale::new(43.82798767089844),
world_scale_factors: (1.0, 1.0),
local_scale: (1.0, 1.0),
allow_snapping: true,
force_scissor_rect: false,
},
];
get_surface_rects(
SurfaceIndex(1),
&PictureCompositeMode::Blit(BlitReason::ISOLATE),
SurfaceIndex(0),
&mut surfaces,
&spatial_tree,
MAX_SURFACE_SIZE as f32,
false,
);
}
#[test]
fn test_drop_filter_dirty_region_outside_prim() {
// Ensure that if we have a drop-filter where the content of the
// shadow is outside the dirty rect, but blurred pixels from that
// content will affect the dirty rect, that we correctly calculate
// the required region of the drop-filter input
use api::Shadow;
use crate::spatial_tree::{SceneSpatialTree, SpatialTree};
let mut cst = SceneSpatialTree::new();
let root_reference_frame_index = cst.root_reference_frame_index();
let mut spatial_tree = SpatialTree::new();
spatial_tree.apply_updates(cst.end_frame_and_get_pending_updates());
spatial_tree.update_tree(&SceneProperties::new());
let map_local_to_surface = SpaceMapper::new_with_target(
root_reference_frame_index,
root_reference_frame_index,
PictureRect::max_rect(),
&spatial_tree,
);
let mut surfaces = vec![
SurfaceInfo {
unclipped_local_rect: PictureRect::max_rect(),
clipped_local_rect: PictureRect::max_rect(),
is_opaque: true,
clipping_rect: PictureRect::max_rect(),
map_local_to_surface: map_local_to_surface.clone(),
raster_spatial_node_index: root_reference_frame_index,
surface_spatial_node_index: root_reference_frame_index,
device_pixel_scale: DevicePixelScale::new(1.0),
world_scale_factors: (1.0, 1.0),
local_scale: (1.0, 1.0),
allow_snapping: true,
force_scissor_rect: false,
},
SurfaceInfo {
unclipped_local_rect: PictureRect::new(
PicturePoint::new(0.0, 0.0),
PicturePoint::new(750.0, 450.0),
),
clipped_local_rect: PictureRect::new(
PicturePoint::new(0.0, 0.0),
PicturePoint::new(750.0, 450.0),
),
is_opaque: true,
clipping_rect: PictureRect::max_rect(),
map_local_to_surface,
raster_spatial_node_index: root_reference_frame_index,
surface_spatial_node_index: root_reference_frame_index,
device_pixel_scale: DevicePixelScale::new(1.0),
world_scale_factors: (1.0, 1.0),
local_scale: (1.0, 1.0),
allow_snapping: true,
force_scissor_rect: false,
},
];
let shadows = smallvec![
Shadow {
offset: LayoutVector2D::zero(),
color: ColorF::BLACK,
blur_radius: 75.0,
},
];
let composite_mode = PictureCompositeMode::Filter(Filter::DropShadows(shadows));
// Ensure we get a valid and correct render task size when dirty region covers entire screen
let info = get_surface_rects(
SurfaceIndex(1),
&composite_mode,
SurfaceIndex(0),
&mut surfaces,
&spatial_tree,
MAX_SURFACE_SIZE as f32,
false,
).expect("No surface rect");
assert_eq!(info.task_size, DeviceIntSize::new(1200, 900));
// Ensure we get a valid and correct render task size when dirty region is outside filter content
surfaces[0].clipping_rect = PictureRect::new(
PicturePoint::new(768.0, 128.0),
PicturePoint::new(1024.0, 256.0),
);
let info = get_surface_rects(
SurfaceIndex(1),
&composite_mode,
SurfaceIndex(0),
&mut surfaces,
&spatial_tree,
MAX_SURFACE_SIZE as f32,
false,
).expect("No surface rect");
assert_eq!(info.task_size, DeviceIntSize::new(432, 578));
}