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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
#ifndef MOZILLA_GFX_COMPOSITORHITTESTINFO_H_
#define MOZILLA_GFX_COMPOSITORHITTESTINFO_H_
#include "mozilla/EnumSet.h"
#include "mozilla/EnumTypeTraits.h"
namespace mozilla {
namespace gfx {
// This set of flags is used to figure out what information a frame has
// that is relevant to hit-testing in the compositor. The flags are
// intentionally set up so that if all of them are 0 the item is effectively
// invisible to hit-testing, and no information for this frame needs to be
// sent to the compositor.
// Each enumerator is annotated with the value it contributes to an
// EnumSet (2 ^ <value of enumerator>), in hexadecimal.
enum class CompositorHitTestFlags : uint8_t {
// The frame participates in hit-testing
eVisibleToHitTest = 0, // 0x0001
// The frame may have odd shapes that requires the main thread to do accurate
// hit-testing.
eIrregularArea, // 0x0002
// The frame has APZ-aware listeners and so inputs targeted at this area
// need to be handled by the main thread before APZ can use them, as they
// might be prevent-defaulted.
eApzAwareListeners, // 0x0004
// This is an inactive scrollframe or unlayerized scrollthumb. In this state
// it cannot be used by APZ for async scrolling, so APZ will defer to the main
// thread.
eInactiveScrollframe, // 0x0008
// The touch action flags are set up so that the default of
// touch-action:auto on an element leaves all the flags as 0.
eTouchActionPanXDisabled, // 0x0010
eTouchActionPanYDisabled, // 0x0020
eTouchActionPinchZoomDisabled, // 0x0040
eTouchActionAnimatingZoomDisabled, // 0x0080
// The frame is a scrollbar or a subframe inside a scrollbar (including
// scroll thumbs)
eScrollbar, // 0x0100
// The frame is a scrollthumb. If this is set then eScrollbar will also be
// set, unless gecko somehow generates a scroll thumb without a containing
// scrollbar.
eScrollbarThumb, // 0x0200
// If eScrollbar is set, this flag indicates if the scrollbar is a vertical
// one (if set) or a horizontal one (if not set)
eScrollbarVertical, // 0x0400
// Events targeting this frame should only be processed if a target
// confirmation is received from the main thread. If no such confirmation
// is received within a timeout period, the event may be dropped.
// Only meaningful in combination with eDispatchToContent.
eRequiresTargetConfirmation, // 0x0800
// Bits 0x1000, 0x2000, 0x4000, and 0x8000 are used by SideBitsPacked in
// WebRenderAPI.cpp when we pack SideBits and CompositorHitTestInfo into a
// uint16_t and pass in into webrender to store in the item tag.
};
using CompositorHitTestInfo = EnumSet<CompositorHitTestFlags, uint32_t>;
// A CompositorHitTestInfo with none of the flags set
constexpr CompositorHitTestInfo CompositorHitTestInvisibleToHit;
// Mask to check for all the touch-action flags at once
constexpr CompositorHitTestInfo CompositorHitTestTouchActionMask(
CompositorHitTestFlags::eTouchActionPanXDisabled,
CompositorHitTestFlags::eTouchActionPanYDisabled,
CompositorHitTestFlags::eTouchActionPinchZoomDisabled,
CompositorHitTestFlags::eTouchActionAnimatingZoomDisabled);
// Mask to check all the flags that involve APZ waiting for results from the
// main thread
constexpr CompositorHitTestInfo CompositorHitTestDispatchToContent(
CompositorHitTestFlags::eIrregularArea,
CompositorHitTestFlags::eApzAwareListeners,
CompositorHitTestFlags::eInactiveScrollframe);
} // namespace gfx
// Used for IPDL serialization. The 'value' have to be the biggest enum from
// CompositorHitTestFlags.
template <>
struct MaxEnumValue<::mozilla::gfx::CompositorHitTestFlags> {
static constexpr unsigned int value = static_cast<unsigned int>(
gfx::CompositorHitTestFlags::eRequiresTargetConfirmation);
};
namespace gfx {
// Checks if the CompositorHitTestFlags max enum value is less than N.
template <int N>
static constexpr bool DoesCompositorHitTestInfoFitIntoBits() {
if (MaxEnumValue<CompositorHitTestInfo::valueType>::value < N) {
return true;
}
return false;
}
} // namespace gfx
} // namespace mozilla
#endif /* MOZILLA_GFX_COMPOSITORHITTESTINFO_H_ */