Add m-esr52 at 52.6.0

1 files changed, 726 insertions, 0 deletions

diff --git a/gfx/layers/Compositor.h b/gfx/layers/Compositor.h
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+++ b/gfx/layers/Compositor.h
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+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+* 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_COMPOSITOR_H
+#define MOZILLA_GFX_COMPOSITOR_H
+
+#include "Units.h"                      // for ScreenPoint
+#include "mozilla/Assertions.h"         // for MOZ_ASSERT, etc
+#include "mozilla/RefPtr.h"             // for already_AddRefed, RefCounted
+#include "mozilla/gfx/2D.h"             // for DrawTarget
+#include "mozilla/gfx/MatrixFwd.h"      // for Matrix4x4
+#include "mozilla/gfx/Point.h"          // for IntSize, Point
+#include "mozilla/gfx/Polygon.h"        // for Polygon3D
+#include "mozilla/gfx/Rect.h"           // for Rect, IntRect
+#include "mozilla/gfx/Types.h"          // for Float
+#include "mozilla/gfx/Triangle.h"       // for Triangle, TexturedTriangle
+#include "mozilla/layers/CompositorTypes.h"  // for DiagnosticTypes, etc
+#include "mozilla/layers/LayersTypes.h"  // for LayersBackend
+#include "mozilla/widget/CompositorWidget.h"
+#include "nsISupportsImpl.h"            // for MOZ_COUNT_CTOR, etc
+#include "nsRegion.h"
+#include <vector>
+#include "mozilla/WidgetUtils.h"
+
+/**
+ * Different elements of a web pages are rendered into separate "layers" before
+ * they are flattened into the final image that is brought to the screen.
+ * See Layers.h for more informations about layers and why we use retained
+ * structures.
+ * Most of the documentation for layers is directly in the source code in the
+ * form of doc comments. An overview can also be found in the the wiki:
+ * https://wiki.mozilla.org/Gecko:Overview#Graphics
+ *
+ *
+ * # Main interfaces and abstractions
+ *
+ *  - Layer, ShadowableLayer and LayerComposite
+ *    (see Layers.h and ipc/ShadowLayers.h)
+ *  - CompositableClient and CompositableHost
+ *    (client/CompositableClient.h composite/CompositableHost.h)
+ *  - TextureClient and TextureHost
+ *    (client/TextureClient.h composite/TextureHost.h)
+ *  - TextureSource
+ *    (composite/TextureHost.h)
+ *  - Forwarders
+ *    (ipc/CompositableForwarder.h ipc/ShadowLayers.h)
+ *  - Compositor
+ *    (this file)
+ *  - IPDL protocols
+ *    (.ipdl files under the gfx/layers/ipc directory)
+ *
+ * The *Client and Shadowable* classes are always used on the content thread.
+ * Forwarders are always used on the content thread.
+ * The *Host and Shadow* classes are always used on the compositor thread.
+ * Compositors, TextureSource, and Effects are always used on the compositor
+ * thread.
+ * Most enums and constants are declared in LayersTypes.h and CompositorTypes.h.
+ *
+ *
+ * # Texture transfer
+ *
+ * Most layer classes own a Compositable plus some extra information like
+ * transforms and clip rects. They are platform independent.
+ * Compositable classes manipulate Texture objects and are reponsible for
+ * things like tiling, buffer rotation or double buffering. Compositables
+ * are also platform-independent. Examples of compositable classes are:
+ *  - ImageClient
+ *  - CanvasClient
+ *  - ContentHost
+ *  - etc.
+ * Texture classes (TextureClient and TextureHost) are thin abstractions over
+ * platform-dependent texture memory. They are maniplulated by compositables
+ * and don't know about buffer rotations and such. The purposes of TextureClient
+ * and TextureHost are to synchronize, serialize and deserialize texture data.
+ * TextureHosts provide access to TextureSources that are views on the
+ * Texture data providing the necessary api for Compositor backend to composite
+ * them.
+ *
+ * Compositable and Texture clients and hosts are created using factory methods.
+ * They should only be created by using their constructor in exceptional
+ * circumstances. The factory methods are located:
+ *    TextureClient       - CompositableClient::CreateTextureClient
+ *    TextureHost         - TextureHost::CreateTextureHost, which calls a
+ *                          platform-specific function, e.g., CreateTextureHostOGL
+ *    CompositableClient  - in the appropriate subclass, e.g.,
+ *                          CanvasClient::CreateCanvasClient
+ *    CompositableHost    - CompositableHost::Create
+ *
+ *
+ * # IPDL
+ *
+ * If off-main-thread compositing (OMTC) is enabled, compositing is performed
+ * in a dedicated thread. In some setups compositing happens in a dedicated
+ * process. Documentation may refer to either the compositor thread or the
+ * compositor process.
+ * See explanations in ShadowLayers.h.
+ *
+ *
+ * # Backend implementations
+ *
+ * Compositor backends like OpenGL or flavours of D3D live in their own directory
+ * under gfx/layers/. To add a new backend, implement at least the following
+ * interfaces:
+ * - Compositor (ex. CompositorOGL)
+ * - TextureHost (ex. SurfaceTextureHost)
+ * Depending on the type of data that needs to be serialized, you may need to
+ * add specific TextureClient implementations.
+ */
+
+class nsIWidget;
+
+namespace mozilla {
+namespace gfx {
+class Matrix;
+class DrawTarget;
+class DataSourceSurface;
+} // namespace gfx
+
+namespace layers {
+
+struct Effect;
+struct EffectChain;
+class Image;
+class ImageHostOverlay;
+class Layer;
+class TextureSource;
+class DataTextureSource;
+class CompositingRenderTarget;
+class CompositorBridgeParent;
+class LayerManagerComposite;
+class CompositorOGL;
+class CompositorD3D9;
+class CompositorD3D11;
+class BasicCompositor;
+class TextureHost;
+class TextureReadLock;
+
+enum SurfaceInitMode
+{
+  INIT_MODE_NONE,
+  INIT_MODE_CLEAR
+};
+
+/**
+ * Common interface for compositor backends.
+ *
+ * Compositor provides a cross-platform interface to a set of operations for
+ * compositing quads. Compositor knows nothing about the layer tree. It must be
+ * told everything about each composited quad - contents, location, transform,
+ * opacity, etc.
+ *
+ * In theory it should be possible for different widgets to use the same
+ * compositor. In practice, we use one compositor per window.
+ *
+ * # Usage
+ *
+ * For an example of a user of Compositor, see LayerManagerComposite.
+ *
+ * Initialization: create a Compositor object, call Initialize().
+ *
+ * Destruction: destroy any resources associated with the compositor, call
+ * Destroy(), delete the Compositor object.
+ *
+ * Composition:
+ *  call BeginFrame,
+ *  for each quad to be composited:
+ *    call MakeCurrent if necessary (not necessary if no other context has been
+ *      made current),
+ *    take care of any texture upload required to composite the quad, this step
+ *      is backend-dependent,
+ *    construct an EffectChain for the quad,
+ *    call DrawQuad,
+ *  call EndFrame.
+ * If the compositor is usually used for compositing but compositing is
+ * temporarily done without the compositor, call EndFrameForExternalComposition
+ * after compositing each frame so the compositor can remain internally
+ * consistent.
+ *
+ * By default, the compositor will render to the screen, to render to a target,
+ * call SetTargetContext or SetRenderTarget, the latter with a target created
+ * by CreateRenderTarget or CreateRenderTargetFromSource.
+ *
+ * The target and viewport methods can be called before any DrawQuad call and
+ * affect any subsequent DrawQuad calls.
+ */
+class Compositor
+{
+protected:
+  virtual ~Compositor();
+
+public:
+  NS_INLINE_DECL_REFCOUNTING(Compositor)
+
+  explicit Compositor(widget::CompositorWidget* aWidget,
+                      CompositorBridgeParent* aParent = nullptr);
+
+  virtual already_AddRefed<DataTextureSource> CreateDataTextureSource(TextureFlags aFlags = TextureFlags::NO_FLAGS) = 0;
+
+  virtual already_AddRefed<DataTextureSource>
+  CreateDataTextureSourceAround(gfx::DataSourceSurface* aSurface) { return nullptr; }
+
+  virtual already_AddRefed<DataTextureSource>
+  CreateDataTextureSourceAroundYCbCr(TextureHost* aTexture) { return nullptr; }
+
+  virtual bool Initialize(nsCString* const out_failureReason) = 0;
+  virtual void Destroy();
+  bool IsDestroyed() const { return mIsDestroyed; }
+
+  virtual void DetachWidget() { mWidget = nullptr; }
+
+  /**
+   * Return true if the effect type is supported.
+   *
+   * By default Compositor implementations should support all effects but in
+   * some rare cases it is not possible to support an effect efficiently.
+   * This is the case for BasicCompositor with EffectYCbCr.
+   */
+  virtual bool SupportsEffect(EffectTypes aEffect) { return true; }
+
+  /**
+   * Request a texture host identifier that may be used for creating textures
+   * across process or thread boundaries that are compatible with this
+   * compositor.
+   */
+  virtual TextureFactoryIdentifier GetTextureFactoryIdentifier() = 0;
+
+  /**
+   * Properties of the compositor.
+   */
+  virtual bool CanUseCanvasLayerForSize(const gfx::IntSize& aSize) = 0;
+  virtual int32_t GetMaxTextureSize() const = 0;
+
+  /**
+   * Set the target for rendering. Results will have been written to aTarget by
+   * the time that EndFrame returns.
+   *
+   * If this method is not used, or we pass in nullptr, we target the compositor's
+   * usual swap chain and render to the screen.
+   */
+  void SetTargetContext(gfx::DrawTarget* aTarget, const gfx::IntRect& aRect)
+  {
+    mTarget = aTarget;
+    mTargetBounds = aRect;
+  }
+  gfx::DrawTarget* GetTargetContext() const
+  {
+    return mTarget;
+  }
+  void ClearTargetContext()
+  {
+    mTarget = nullptr;
+  }
+
+  typedef uint32_t MakeCurrentFlags;
+  static const MakeCurrentFlags ForceMakeCurrent = 0x1;
+  /**
+   * Make this compositor's rendering context the current context for the
+   * underlying graphics API. This may be a global operation, depending on the
+   * API. Our context will remain the current one until someone else changes it.
+   *
+   * Clients of the compositor should call this at the start of the compositing
+   * process, it might be required by texture uploads etc.
+   *
+   * If aFlags == ForceMakeCurrent then we will (re-)set our context on the
+   * underlying API even if it is already the current context.
+   */
+  virtual void MakeCurrent(MakeCurrentFlags aFlags = 0) = 0;
+
+  /**
+   * Creates a Surface that can be used as a rendering target by this
+   * compositor.
+   */
+  virtual already_AddRefed<CompositingRenderTarget>
+  CreateRenderTarget(const gfx::IntRect& aRect, SurfaceInitMode aInit) = 0;
+
+  /**
+   * Creates a Surface that can be used as a rendering target by this
+   * compositor, and initializes the surface by copying from aSource.
+   * If aSource is null, then the current screen buffer is used as source.
+   *
+   * aSourcePoint specifies the point in aSource to copy data from.
+   */
+  virtual already_AddRefed<CompositingRenderTarget>
+  CreateRenderTargetFromSource(const gfx::IntRect& aRect,
+                               const CompositingRenderTarget* aSource,
+                               const gfx::IntPoint& aSourcePoint) = 0;
+
+  /**
+   * Sets the given surface as the target for subsequent calls to DrawQuad.
+   * Passing null as aSurface sets the screen as the target.
+   */
+  virtual void SetRenderTarget(CompositingRenderTarget* aSurface) = 0;
+
+  /**
+   * Returns the current target for rendering. Will return null if we are
+   * rendering to the screen.
+   */
+  virtual CompositingRenderTarget* GetCurrentRenderTarget() const = 0;
+
+  /**
+   * Mostly the compositor will pull the size from a widget and this method will
+   * be ignored, but compositor implementations are free to use it if they like.
+   */
+  virtual void SetDestinationSurfaceSize(const gfx::IntSize& aSize) = 0;
+
+  /**
+   * Declare an offset to use when rendering layers. This will be ignored when
+   * rendering to a target instead of the screen.
+   */
+  virtual void SetScreenRenderOffset(const ScreenPoint& aOffset) = 0;
+
+  void DrawGeometry(const gfx::Rect& aRect,
+                    const gfx::IntRect& aClipRect,
+                    const EffectChain &aEffectChain,
+                    gfx::Float aOpacity,
+                    const gfx::Matrix4x4& aTransform,
+                    const gfx::Rect& aVisibleRect,
+                    const Maybe<gfx::Polygon3D>& aGeometry);
+
+  void DrawGeometry(const gfx::Rect& aRect,
+                    const gfx::IntRect& aClipRect,
+                    const EffectChain &aEffectChain,
+                    gfx::Float aOpacity,
+                    const gfx::Matrix4x4& aTransform,
+                    const Maybe<gfx::Polygon3D>& aGeometry)
+  {
+    DrawGeometry(aRect, aClipRect, aEffectChain, aOpacity,
+                 aTransform, aRect, aGeometry);
+  }
+
+  /**
+   * Tell the compositor to draw a quad. What to do draw and how it is
+   * drawn is specified by aEffectChain. aRect is the quad to draw, in user space.
+   * aTransform transforms from user space to screen space. If texture coords are
+   * required, these will be in the primary effect in the effect chain.
+   * aVisibleRect is used to determine which edges should be antialiased,
+   * without applying the effect to the inner edges of a tiled layer.
+   */
+  virtual void DrawQuad(const gfx::Rect& aRect, const gfx::IntRect& aClipRect,
+                        const EffectChain& aEffectChain,
+                        gfx::Float aOpacity, const gfx::Matrix4x4& aTransform,
+                        const gfx::Rect& aVisibleRect) = 0;
+
+  /**
+   * Overload of DrawQuad, with aVisibleRect defaulted to the value of aRect.
+   * Use this when you are drawing a single quad that is not part of a tiled
+   * layer.
+   */
+  void DrawQuad(const gfx::Rect& aRect, const gfx::IntRect& aClipRect,
+                        const EffectChain& aEffectChain,
+                        gfx::Float aOpacity, const gfx::Matrix4x4& aTransform) {
+      DrawQuad(aRect, aClipRect, aEffectChain, aOpacity, aTransform, aRect);
+  }
+
+  virtual void DrawTriangle(const gfx::TexturedTriangle& aTriangle,
+                            const gfx::IntRect& aClipRect,
+                            const EffectChain& aEffectChain,
+                            gfx::Float aOpacity,
+                            const gfx::Matrix4x4& aTransform,
+                            const gfx::Rect& aVisibleRect)
+  {
+    MOZ_CRASH("Compositor::DrawTriangle is not implemented for the current platform!");
+  }
+
+  /**
+   * Draw an unfilled solid color rect. Typically used for debugging overlays.
+   */
+  void SlowDrawRect(const gfx::Rect& aRect, const gfx::Color& color,
+                const gfx::IntRect& aClipRect = gfx::IntRect(),
+                const gfx::Matrix4x4& aTransform = gfx::Matrix4x4(),
+                int aStrokeWidth = 1);
+
+  /**
+   * Draw a solid color filled rect. This is a simple DrawQuad helper.
+   */
+  void FillRect(const gfx::Rect& aRect, const gfx::Color& color,
+                    const gfx::IntRect& aClipRect = gfx::IntRect(),
+                    const gfx::Matrix4x4& aTransform = gfx::Matrix4x4());
+
+  void SetClearColor(const gfx::Color& aColor) {
+    mClearColor = aColor;
+  }
+
+  void SetDefaultClearColor(const gfx::Color& aColor) {
+    mDefaultClearColor = aColor;
+  }
+
+  void SetClearColorToDefault() {
+    mClearColor = mDefaultClearColor;
+  }
+
+  /*
+   * Clear aRect on current render target.
+   */
+  virtual void ClearRect(const gfx::Rect& aRect) = 0;
+
+  /**
+   * Start a new frame.
+   *
+   * aInvalidRect is the invalid region of the screen; it can be ignored for
+   * compositors where the performance for compositing the entire window is
+   * sufficient.
+   *
+   * aClipRectIn is the clip rect for the window in window space (optional).
+   * aTransform is the transform from user space to window space.
+   * aRenderBounds bounding rect for rendering, in user space.
+   *
+   * If aClipRectIn is null, this method sets *aClipRectOut to the clip rect
+   * actually used for rendering (if aClipRectIn is non-null, we will use that
+   * for the clip rect).
+   *
+   * If aRenderBoundsOut is non-null, it will be set to the render bounds
+   * actually used by the compositor in window space. If aRenderBoundsOut
+   * is returned empty, composition should be aborted.
+   *
+   * If aOpaque is true, then all of aInvalidRegion will be drawn to with
+   * opaque content.
+   */
+  virtual void BeginFrame(const nsIntRegion& aInvalidRegion,
+                          const gfx::IntRect* aClipRectIn,
+                          const gfx::IntRect& aRenderBounds,
+                          const nsIntRegion& aOpaqueRegion,
+                          gfx::IntRect* aClipRectOut = nullptr,
+                          gfx::IntRect* aRenderBoundsOut = nullptr) = 0;
+
+  /**
+   * Flush the current frame to the screen and tidy up.
+   *
+   * Derived class overriding this should call Compositor::EndFrame.
+   */
+  virtual void EndFrame();
+
+  virtual void SetDispAcquireFence(Layer* aLayer);
+
+  /**
+   * Post-rendering stuff if the rendering is done outside of this Compositor
+   * e.g., by Composer2D.
+   * aTransform is the transform from user space to window space.
+   */
+  virtual void EndFrameForExternalComposition(const gfx::Matrix& aTransform) = 0;
+
+  /**
+   * Whether textures created by this compositor can receive partial updates.
+   */
+  virtual bool SupportsPartialTextureUpdate() = 0;
+
+  void SetDiagnosticTypes(DiagnosticTypes aDiagnostics)
+  {
+    mDiagnosticTypes = aDiagnostics;
+  }
+
+  DiagnosticTypes GetDiagnosticTypes() const
+  {
+    return mDiagnosticTypes;
+  }
+
+  void DrawDiagnostics(DiagnosticFlags aFlags,
+                       const gfx::Rect& visibleRect,
+                       const gfx::IntRect& aClipRect,
+                       const gfx::Matrix4x4& transform,
+                       uint32_t aFlashCounter = DIAGNOSTIC_FLASH_COUNTER_MAX);
+
+  void DrawDiagnostics(DiagnosticFlags aFlags,
+                       const nsIntRegion& visibleRegion,
+                       const gfx::IntRect& aClipRect,
+                       const gfx::Matrix4x4& transform,
+                       uint32_t aFlashCounter = DIAGNOSTIC_FLASH_COUNTER_MAX);
+
+#ifdef MOZ_DUMP_PAINTING
+  virtual const char* Name() const = 0;
+#endif // MOZ_DUMP_PAINTING
+
+  virtual LayersBackend GetBackendType() const = 0;
+
+  virtual CompositorOGL* AsCompositorOGL() { return nullptr; }
+  virtual CompositorD3D9* AsCompositorD3D9() { return nullptr; }
+  virtual CompositorD3D11* AsCompositorD3D11() { return nullptr; }
+  virtual BasicCompositor* AsBasicCompositor() { return nullptr; }
+
+  /**
+   * Each Compositor has a unique ID.
+   * This ID is used to keep references to each Compositor in a map accessed
+   * from the compositor thread only, so that async compositables can find
+   * the right compositor parent and schedule compositing even if the compositor
+   * changed.
+   */
+  uint32_t GetCompositorID() const
+  {
+    return mCompositorID;
+  }
+  void SetCompositorID(uint32_t aID)
+  {
+    MOZ_ASSERT(mCompositorID == 0, "The compositor ID must be set only once.");
+    mCompositorID = aID;
+  }
+
+  /**
+   * Notify the compositor that composition is being paused. This allows the
+   * compositor to temporarily release any resources.
+   * Between calling Pause and Resume, compositing may fail.
+   */
+  virtual void Pause() {}
+  /**
+   * Notify the compositor that composition is being resumed. The compositor
+   * regain any resources it requires for compositing.
+   * Returns true if succeeded.
+   */
+  virtual bool Resume() { return true; }
+
+  /**
+   * Call before rendering begins to ensure the compositor is ready to
+   * composite. Returns false if rendering should be aborted.
+   */
+  virtual bool Ready() { return true; }
+
+  virtual void ForcePresent() { }
+
+  virtual bool IsPendingComposite() { return false; }
+
+  virtual void FinishPendingComposite() {}
+
+  widget::CompositorWidget* GetWidget() const { return mWidget; }
+
+  virtual bool HasImageHostOverlays() { return false; }
+
+  virtual void AddImageHostOverlay(ImageHostOverlay* aOverlay) {}
+
+  virtual void RemoveImageHostOverlay(ImageHostOverlay* aOverlay) {}
+
+  /**
+   * Debug-build assertion that can be called to ensure code is running on the
+   * compositor thread.
+   */
+  static void AssertOnCompositorThread();
+
+  size_t GetFillRatio() {
+    float fillRatio = 0;
+    if (mPixelsFilled > 0 && mPixelsPerFrame > 0) {
+      fillRatio = 100.0f * float(mPixelsFilled) / float(mPixelsPerFrame);
+      if (fillRatio > 999.0f) {
+        fillRatio = 999.0f;
+      }
+    }
+    return fillRatio;
+  }
+
+  ScreenRotation GetScreenRotation() const {
+    return mScreenRotation;
+  }
+  void SetScreenRotation(ScreenRotation aRotation) {
+    mScreenRotation = aRotation;
+  }
+
+  TimeStamp GetCompositionTime() const {
+    return mCompositionTime;
+  }
+  void SetCompositionTime(TimeStamp aTimeStamp) {
+    mCompositionTime = aTimeStamp;
+    if (!mCompositionTime.IsNull() && !mCompositeUntilTime.IsNull() &&
+        mCompositionTime >= mCompositeUntilTime) {
+      mCompositeUntilTime = TimeStamp();
+    }
+  }
+
+  void CompositeUntil(TimeStamp aTimeStamp) {
+    if (mCompositeUntilTime.IsNull() ||
+        mCompositeUntilTime < aTimeStamp) {
+      mCompositeUntilTime = aTimeStamp;
+    }
+  }
+  TimeStamp GetCompositeUntilTime() const {
+    return mCompositeUntilTime;
+  }
+
+  // A stale Compositor has no CompositorBridgeParent; it will not process
+  // frames and should not be used.
+  void SetInvalid();
+  bool IsValid() const;
+  CompositorBridgeParent* GetCompositorBridgeParent() const {
+    return mParent;
+  }
+
+  /// Most compositor backends operate asynchronously under the hood. This
+  /// means that when a layer stops using a texture it is often desirable to
+  /// wait for the end of the next composition before releasing the texture's
+  /// ReadLock.
+  /// This function provides a convenient way to do this delayed unlocking, if
+  /// the texture itself requires it.
+  void UnlockAfterComposition(TextureHost* aTexture);
+
+  /// Most compositor backends operate asynchronously under the hood. This
+  /// means that when a layer stops using a texture it is often desirable to
+  /// wait for the end of the next composition before NotifyNotUsed() call.
+  /// This function provides a convenient way to do this delayed NotifyNotUsed()
+  /// call, if the texture itself requires it.
+  /// See bug 1260611 and bug 1252835
+  void NotifyNotUsedAfterComposition(TextureHost* aTextureHost);
+
+  void FlushPendingNotifyNotUsed();
+
+protected:
+  void DrawDiagnosticsInternal(DiagnosticFlags aFlags,
+                               const gfx::Rect& aVisibleRect,
+                               const gfx::IntRect& aClipRect,
+                               const gfx::Matrix4x4& transform,
+                               uint32_t aFlashCounter);
+
+  bool ShouldDrawDiagnostics(DiagnosticFlags);
+
+  // Should be called at the end of each composition.
+  void ReadUnlockTextures();
+
+  /**
+   * Given a layer rect, clip, and transform, compute the area of the backdrop that
+   * needs to be copied for mix-blending. The output transform translates from 0..1
+   * space into the backdrop rect space.
+   *
+   * The transformed layer quad is also optionally returned - this is the same as
+   * the result rect, before rounding.
+   */
+  gfx::IntRect ComputeBackdropCopyRect(const gfx::Rect& aRect,
+                                       const gfx::IntRect& aClipRect,
+                                       const gfx::Matrix4x4& aTransform,
+                                       gfx::Matrix4x4* aOutTransform,
+                                       gfx::Rect* aOutLayerQuad = nullptr);
+
+  gfx::IntRect ComputeBackdropCopyRect(const gfx::Triangle& aTriangle,
+                                       const gfx::IntRect& aClipRect,
+                                       const gfx::Matrix4x4& aTransform,
+                                       gfx::Matrix4x4* aOutTransform,
+                                       gfx::Rect* aOutLayerQuad = nullptr);
+
+
+  /**
+   * An array of locks that will need to be unlocked after the next composition.
+   */
+  nsTArray<RefPtr<TextureHost>> mUnlockAfterComposition;
+
+  /**
+   * An array of TextureHosts that will need to call NotifyNotUsed() after the next composition.
+   */
+  nsTArray<RefPtr<TextureHost>> mNotifyNotUsedAfterComposition;
+
+  /**
+   * Last Composition end time.
+   */
+  TimeStamp mLastCompositionEndTime;
+
+  /**
+   * Render time for the current composition.
+   */
+  TimeStamp mCompositionTime;
+  /**
+   * When nonnull, during rendering, some compositable indicated that it will
+   * change its rendering at this time. In order not to miss it, we composite
+   * on every vsync until this time occurs (this is the latest such time).
+   */
+  TimeStamp mCompositeUntilTime;
+
+  uint32_t mCompositorID;
+  DiagnosticTypes mDiagnosticTypes;
+  CompositorBridgeParent* mParent;
+
+  /**
+   * We keep track of the total number of pixels filled as we composite the
+   * current frame. This value is an approximation and is not accurate,
+   * especially in the presence of transforms.
+   */
+  size_t mPixelsPerFrame;
+  size_t mPixelsFilled;
+
+  ScreenRotation mScreenRotation;
+
+  RefPtr<gfx::DrawTarget> mTarget;
+  gfx::IntRect mTargetBounds;
+
+  widget::CompositorWidget* mWidget;
+
+  bool mIsDestroyed;
+
+  gfx::Color mClearColor;
+  gfx::Color mDefaultClearColor;
+
+private:
+  static LayersBackend sBackend;
+
+};
+
+// Returns the number of rects. (Up to 4)
+typedef gfx::Rect decomposedRectArrayT[4];
+size_t DecomposeIntoNoRepeatRects(const gfx::Rect& aRect,
+                                  const gfx::Rect& aTexCoordRect,
+                                  decomposedRectArrayT* aLayerRects,
+                                  decomposedRectArrayT* aTextureRects);
+
+static inline bool
+BlendOpIsMixBlendMode(gfx::CompositionOp aOp)
+{
+  switch (aOp) {
+  case gfx::CompositionOp::OP_MULTIPLY:
+  case gfx::CompositionOp::OP_SCREEN:
+  case gfx::CompositionOp::OP_OVERLAY:
+  case gfx::CompositionOp::OP_DARKEN:
+  case gfx::CompositionOp::OP_LIGHTEN:
+  case gfx::CompositionOp::OP_COLOR_DODGE:
+  case gfx::CompositionOp::OP_COLOR_BURN:
+  case gfx::CompositionOp::OP_HARD_LIGHT:
+  case gfx::CompositionOp::OP_SOFT_LIGHT:
+  case gfx::CompositionOp::OP_DIFFERENCE:
+  case gfx::CompositionOp::OP_EXCLUSION:
+  case gfx::CompositionOp::OP_HUE:
+  case gfx::CompositionOp::OP_SATURATION:
+  case gfx::CompositionOp::OP_COLOR:
+  case gfx::CompositionOp::OP_LUMINOSITY:
+    return true;
+  default:
+    return false;
+  }
+}
+
+} // namespace layers
+} // namespace mozilla
+
+#endif /* MOZILLA_GFX_COMPOSITOR_H */