Quelle CompositorHitTestInfo.h Sprache: C

/* -*- 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#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_ */

quality100%

¤ Dauer der Verarbeitung: 0.14 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.