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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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
#include "mozilla/ShapeUtils.h"
#include <cstdlib>
#include "nsCSSRendering.h"
#include "nsLayoutUtils.h"
#include "nsMargin.h"
#include "nsStyleStruct.h"
#include "mozilla/SVGContentUtils.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/gfx/PathHelpers.h"
namespace mozilla {
nscoord ShapeUtils::ComputeShapeRadius(const StyleShapeRadius& aType,
const nscoord aCenter,
const nscoord aPosMin,
const nscoord aPosMax) {
MOZ_ASSERT(aType.IsFarthestSide() || aType.IsClosestSide());
nscoord dist1 = std::abs(aPosMin - aCenter);
nscoord dist2 = std::abs(aPosMax - aCenter);
nscoord length = 0;
if (aType.IsFarthestSide()) {
length = dist1 > dist2 ? dist1 : dist2;
} else {
length = dist1 > dist2 ? dist2 : dist1;
}
return length;
}
nsPoint ShapeUtils::ComputePosition(const StylePosition& aPosition,
const nsRect& aRefBox) {
nsPoint topLeft, anchor;
nsSize size(aRefBox.Size());
nsImageRenderer::ComputeObjectAnchorPoint(aPosition, size, size, &topLeft,
&anchor);
return anchor + aRefBox.TopLeft();
}
nsPoint ShapeUtils::ComputeCircleOrEllipseCenter(
const StyleBasicShape& aBasicShape, const nsRect& aRefBox) {
MOZ_ASSERT(aBasicShape.IsCircle() || aBasicShape.IsEllipse(),
"The basic shape must be circle() or ellipse!");
const auto& position = aBasicShape.IsCircle()
? aBasicShape.AsCircle().position
: aBasicShape.AsEllipse().position;
// If position is not specified, we use 50% 50%.
if (position.IsAuto()) {
return ComputePosition(StylePosition::FromPercentage(0.5), aRefBox);
}
MOZ_ASSERT(position.IsPosition());
return ComputePosition(position.AsPosition(), aRefBox);
}
nscoord ShapeUtils::ComputeCircleRadius(const StyleBasicShape& aBasicShape,
const nsPoint& aCenter,
const nsRect& aRefBox) {
MOZ_ASSERT(aBasicShape.IsCircle(), "The basic shape must be circle()!");
const auto& radius = aBasicShape.AsCircle().radius;
if (radius.IsLength()) {
return radius.AsLength().Resolve([&] {
// We resolve percent <shape-radius> value for circle() as defined here:
double referenceLength = SVGContentUtils::ComputeNormalizedHypotenuse(
aRefBox.width, aRefBox.height);
return NSToCoordRound(referenceLength);
});
}
nscoord horizontal =
ComputeShapeRadius(radius, aCenter.x, aRefBox.x, aRefBox.XMost());
nscoord vertical =
ComputeShapeRadius(radius, aCenter.y, aRefBox.y, aRefBox.YMost());
return radius.IsFarthestSide() ? std::max(horizontal, vertical)
: std::min(horizontal, vertical);
}
nsSize ShapeUtils::ComputeEllipseRadii(const StyleBasicShape& aBasicShape,
const nsPoint& aCenter,
const nsRect& aRefBox) {
MOZ_ASSERT(aBasicShape.IsEllipse(), "The basic shape must be ellipse()!");
const auto& ellipse = aBasicShape.AsEllipse();
nsSize radii;
if (ellipse.semiaxis_x.IsLength()) {
radii.width = ellipse.semiaxis_x.AsLength().Resolve(aRefBox.width);
} else {
radii.width = ComputeShapeRadius(ellipse.semiaxis_x, aCenter.x, aRefBox.x,
aRefBox.XMost());
}
if (ellipse.semiaxis_y.IsLength()) {
radii.height = ellipse.semiaxis_y.AsLength().Resolve(aRefBox.height);
} else {
radii.height = ComputeShapeRadius(ellipse.semiaxis_y, aCenter.y, aRefBox.y,
aRefBox.YMost());
}
return radii;
}
/* static */
nsRect ShapeUtils::ComputeInsetRect(
const StyleRect<LengthPercentage>& aStyleRect, const nsRect& aRefBox) {
nsMargin inset(aStyleRect._0.Resolve(aRefBox.Height()),
aStyleRect._1.Resolve(aRefBox.Width()),
aStyleRect._2.Resolve(aRefBox.Height()),
aStyleRect._3.Resolve(aRefBox.Width()));
nscoord x = aRefBox.X() + inset.left;
nscoord width = aRefBox.Width() - inset.LeftRight();
nscoord y = aRefBox.Y() + inset.top;
nscoord height = aRefBox.Height() - inset.TopBottom();
// Invert left and right, if necessary.
if (width < 0) {
width *= -1;
x -= width;
}
// Invert top and bottom, if necessary.
if (height < 0) {
height *= -1;
y -= height;
}
return nsRect(x, y, width, height);
}
/* static */
bool ShapeUtils::ComputeRectRadii(const StyleBorderRadius& aBorderRadius,
const nsRect& aRefBox, const nsRect& aRect,
nscoord aRadii[8]) {
return nsIFrame::ComputeBorderRadii(aBorderRadius, aRefBox.Size(),
aRect.Size(), Sides(), aRadii);
}
/* static */
nsTArray<nsPoint> ShapeUtils::ComputePolygonVertices(
const StyleBasicShape& aBasicShape, const nsRect& aRefBox) {
MOZ_ASSERT(aBasicShape.IsPolygon(), "The basic shape must be polygon()!");
auto coords = aBasicShape.AsPolygon().coordinates.AsSpan();
nsTArray<nsPoint> vertices(coords.Length());
for (const StylePolygonCoord<LengthPercentage>& point : coords) {
vertices.AppendElement(nsPoint(point._0.Resolve(aRefBox.width),
point._1.Resolve(aRefBox.height)) +
aRefBox.TopLeft());
}
return vertices;
}
/* static */
static inline gfx::Point ConvertToGfxPoint(const nsPoint& aPoint,
nscoord aAppUnitsPerPixel) {
return {static_cast<gfx::Float>(aPoint.x) /
static_cast<gfx::Float>(aAppUnitsPerPixel),
static_cast<gfx::Float>(aPoint.y) /
static_cast<gfx::Float>(aAppUnitsPerPixel)};
}
/* static */
already_AddRefed<gfx::Path> ShapeUtils::BuildCirclePath(
const StyleBasicShape& aShape, const nsRect& aRefBox,
const nsPoint& aCenter, nscoord aAppUnitsPerPixel,
gfx::PathBuilder* aPathBuilder) {
const nscoord r = ComputeCircleRadius(aShape, aCenter, aRefBox);
aPathBuilder->Arc(
ConvertToGfxPoint(aCenter, aAppUnitsPerPixel),
static_cast<float>(r) / static_cast<float>(aAppUnitsPerPixel), 0.0,
gfx::Float(2.0 * M_PI));
aPathBuilder->Close();
return aPathBuilder->Finish();
}
static inline gfx::Size ConvertToGfxSize(const nsSize& aSize,
nscoord aAppUnitsPerPixel) {
return {static_cast<gfx::Float>(aSize.width) /
static_cast<gfx::Float>(aAppUnitsPerPixel),
static_cast<gfx::Float>(aSize.height) /
static_cast<gfx::Float>(aAppUnitsPerPixel)};
}
/* static */
already_AddRefed<gfx::Path> ShapeUtils::BuildEllipsePath(
const StyleBasicShape& aShape, const nsRect& aRefBox,
const nsPoint& aCenter, nscoord aAppUnitsPerPixel,
gfx::PathBuilder* aPathBuilder) {
const nsSize radii = ComputeEllipseRadii(aShape, aCenter, aRefBox);
EllipseToBezier(aPathBuilder, ConvertToGfxPoint(aCenter, aAppUnitsPerPixel),
ConvertToGfxSize(radii, aAppUnitsPerPixel));
aPathBuilder->Close();
return aPathBuilder->Finish();
}
/* static */
already_AddRefed<gfx::Path> ShapeUtils::BuildPolygonPath(
const StyleBasicShape& aShape, const nsRect& aRefBox,
nscoord aAppUnitsPerPixel, gfx::PathBuilder* aPathBuilder) {
nsTArray<nsPoint> vertices = ComputePolygonVertices(aShape, aRefBox);
if (vertices.IsEmpty()) {
MOZ_ASSERT_UNREACHABLE(
"ComputePolygonVertices() should've given us some vertices!");
} else {
aPathBuilder->MoveTo(NSPointToPoint(vertices[0], aAppUnitsPerPixel));
for (size_t i = 1; i < vertices.Length(); ++i) {
aPathBuilder->LineTo(NSPointToPoint(vertices[i], aAppUnitsPerPixel));
}
}
aPathBuilder->Close();
return aPathBuilder->Finish();
}
/* static */
already_AddRefed<gfx::Path> ShapeUtils::BuildInsetPath(
const StyleBasicShape& aShape, const nsRect& aRefBox,
nscoord aAppUnitsPerPixel, gfx::PathBuilder* aPathBuilder) {
const nsRect insetRect = ComputeInsetRect(aShape.AsRect().rect, aRefBox);
nscoord appUnitsRadii[8];
const bool hasRadii = ComputeRectRadii(aShape.AsRect().round, aRefBox,
insetRect, appUnitsRadii);
return BuildRectPath(insetRect, hasRadii ? appUnitsRadii : nullptr, aRefBox,
aAppUnitsPerPixel, aPathBuilder);
}
/* static */
already_AddRefed<gfx::Path> ShapeUtils::BuildRectPath(
const nsRect& aRect, const nscoord aRadii[8], const nsRect& aRefBox,
nscoord aAppUnitsPerPixel, gfx::PathBuilder* aPathBuilder) {
const gfx::Rect insetRectPixels = NSRectToRect(aRect, aAppUnitsPerPixel);
if (aRadii) {
gfx::RectCornerRadii corners;
nsCSSRendering::ComputePixelRadii(aRadii, aAppUnitsPerPixel, &corners);
AppendRoundedRectToPath(aPathBuilder, insetRectPixels, corners, true);
} else {
AppendRectToPath(aPathBuilder, insetRectPixels, true);
}
return aPathBuilder->Finish();
}
} // namespace mozilla