1 files changed, 286 insertions, 0 deletions
diff --git a/widget/CompositorWidget.h b/widget/CompositorWidget.h
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+++ b/widget/CompositorWidget.h
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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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_widget_CompositorWidget_h__
+#define mozilla_widget_CompositorWidget_h__
+
+#include "nsISupports.h"
+#include "mozilla/RefPtr.h"
+#include "Units.h"
+#include "mozilla/gfx/2D.h"
+#include "mozilla/layers/LayersTypes.h"
+
+class nsIWidget;
+class nsBaseWidget;
+
+namespace mozilla {
+class VsyncObserver;
+namespace layers {
+class Compositor;
+class LayerManagerComposite;
+class Compositor;
+class Composer2D;
+} // namespace layers
+namespace gfx {
+class DrawTarget;
+class SourceSurface;
+} // namespace gfx
+namespace widget {
+
+class WinCompositorWidget;
+class X11CompositorWidget;
+class AndroidCompositorWidget;
+class CompositorWidgetInitData;
+
+// Gecko widgets usually need to communicate with the CompositorWidget with
+// platform-specific messages (for example to update the window size or
+// transparency). This functionality is controlled through a "host". Since
+// this functionality is platform-dependent, it is only forward declared
+// here.
+class CompositorWidgetDelegate;
+
+// Platforms that support out-of-process widgets.
+#if defined(XP_WIN) || defined(MOZ_X11)
+// CompositorWidgetParent should implement CompositorWidget and
+// PCompositorWidgetParent.
+class CompositorWidgetParent;
+
+// CompositorWidgetChild should implement CompositorWidgetDelegate and
+// PCompositorWidgetChild.
+class CompositorWidgetChild;
+
+# define MOZ_WIDGET_SUPPORTS_OOP_COMPOSITING
+#endif
+
+class WidgetRenderingContext
+{
+public:
+#if defined(XP_MACOSX)
+  WidgetRenderingContext() : mLayerManager(nullptr) {}
+  layers::LayerManagerComposite* mLayerManager;
+#elif defined(MOZ_WIDGET_ANDROID)
+  WidgetRenderingContext() : mCompositor(nullptr) {}
+  layers::Compositor* mCompositor;
+#endif
+};
+
+/**
+ * Access to a widget from the compositor is restricted to these methods.
+ */
+class CompositorWidget
+{
+public:
+  NS_INLINE_DECL_REFCOUNTING(mozilla::widget::CompositorWidget)
+
+  /**
+   * Create an in-process compositor widget. aWidget may be ignored if the
+   * platform does not require it.
+   */
+  static RefPtr<CompositorWidget> CreateLocal(const CompositorWidgetInitData& aInitData, nsIWidget* aWidget);
+
+  /**
+   * Called before rendering using OMTC. Returns false when the widget is
+   * not ready to be rendered (for example while the window is closed).
+   *
+   * Always called from the compositing thread, which may be the main-thread if
+   * OMTC is not enabled.
+   */
+  virtual bool PreRender(WidgetRenderingContext* aContext) {
+    return true;
+  }
+
+  /**
+   * Called after rendering using OMTC. Not called when rendering was
+   * cancelled by a negative return value from PreRender.
+   *
+   * Always called from the compositing thread, which may be the main-thread if
+   * OMTC is not enabled.
+   */
+  virtual void PostRender(WidgetRenderingContext* aContext)
+  {}
+
+  /**
+   * Called before the LayerManager draws the layer tree.
+   *
+   * Always called from the compositing thread.
+   */
+  virtual void DrawWindowUnderlay(WidgetRenderingContext* aContext,
+                                  LayoutDeviceIntRect aRect)
+  {}
+
+  /**
+   * Called after the LayerManager draws the layer tree
+   *
+   * Always called from the compositing thread.
+   */
+  virtual void DrawWindowOverlay(WidgetRenderingContext* aContext,
+                                 LayoutDeviceIntRect aRect)
+  {}
+
+  /**
+   * Return a DrawTarget for the window which can be composited into.
+   *
+   * Called by BasicCompositor on the compositor thread for OMTC drawing
+   * before each composition.
+   *
+   * The window may specify its buffer mode. If unspecified, it is assumed
+   * to require double-buffering.
+   */
+  virtual already_AddRefed<gfx::DrawTarget> StartRemoteDrawing();
+  virtual already_AddRefed<gfx::DrawTarget>
+  StartRemoteDrawingInRegion(LayoutDeviceIntRegion& aInvalidRegion,
+                             layers::BufferMode* aBufferMode)
+  {
+    return StartRemoteDrawing();
+  }
+
+  /**
+   * Ensure that what was painted into the DrawTarget returned from
+   * StartRemoteDrawing reaches the screen.
+   *
+   * Called by BasicCompositor on the compositor thread for OMTC drawing
+   * after each composition.
+   */
+  virtual void EndRemoteDrawing()
+  {}
+  virtual void EndRemoteDrawingInRegion(gfx::DrawTarget* aDrawTarget,
+                                        LayoutDeviceIntRegion& aInvalidRegion)
+  {
+    EndRemoteDrawing();
+  }
+
+  /**
+   * Return true when it is better to defer EndRemoteDrawing().
+   *
+   * Called by BasicCompositor on the compositor thread for OMTC drawing
+   * after each composition.
+   */
+  virtual bool NeedsToDeferEndRemoteDrawing() {
+    return false;
+  }
+
+  /**
+   * Called when shutting down the LayerManager to clean-up any cached resources.
+   *
+   * Always called from the compositing thread.
+   */
+  virtual void CleanupWindowEffects()
+  {}
+
+  /**
+   * A hook for the widget to prepare a Compositor, during the latter's initialization.
+   *
+   * If this method returns true, it means that the widget will be able to
+   * present frames from the compoositor.
+   *
+   * Returning false will cause the compositor's initialization to fail, and
+   * a different compositor backend will be used (if any).
+   */
+  virtual bool InitCompositor(layers::Compositor* aCompositor) {
+    return true;
+  }
+
+  /**
+   * Return the size of the drawable area of the widget.
+   */
+  virtual LayoutDeviceIntSize GetClientSize() = 0;
+
+  /**
+   * Return the internal format of the default framebuffer for this
+   * widget.
+   */
+  virtual uint32_t GetGLFrameBufferFormat();
+
+  /**
+   * If this widget has a more efficient composer available for its
+   * native framebuffer, return it.
+   *
+   * This can be called from a non-main thread, but that thread must
+   * hold a strong reference to this.
+   */
+  virtual layers::Composer2D* GetComposer2D() {
+    return nullptr;
+  }
+
+  /*
+   * Access the underlying nsIWidget. This method will be removed when the compositor no longer
+   * depends on nsIWidget on any platform.
+   */
+  virtual nsIWidget* RealWidget() = 0;
+
+  /**
+   * Clean up any resources used by Start/EndRemoteDrawing.
+   *
+   * Called by BasicCompositor on the compositor thread for OMTC drawing
+   * when the compositor is destroyed.
+   */
+  virtual void CleanupRemoteDrawing();
+
+  /**
+   * Return a key that can represent the widget object round-trip across the
+   * CompositorBridge channel. This only needs to be implemented on GTK and
+   * Windows.
+   *
+   * The key must be the nsIWidget pointer cast to a uintptr_t. See
+   * CompositorBridgeChild::RecvHideAllPlugins and
+   * CompositorBridgeParent::SendHideAllPlugins.
+   */
+  virtual uintptr_t GetWidgetKey() {
+    return 0;
+  }
+
+  /**
+   * Create a backbuffer for the software compositor.
+   */
+  virtual already_AddRefed<gfx::DrawTarget>
+  GetBackBufferDrawTarget(gfx::DrawTarget* aScreenTarget,
+                          const LayoutDeviceIntRect& aRect,
+                          const LayoutDeviceIntRect& aClearRect);
+
+  /**
+   * Ensure end of composition to back buffer.
+   *
+   * Called by BasicCompositor on the compositor thread for OMTC drawing
+   * after each composition to back buffer.
+   */
+  virtual already_AddRefed<gfx::SourceSurface> EndBackBufferDrawing();
+
+  /**
+   * Observe or unobserve vsync.
+   */
+  virtual void ObserveVsync(VsyncObserver* aObserver) = 0;
+
+  /**
+   * This is only used by out-of-process compositors.
+   */
+  virtual RefPtr<VsyncObserver> GetVsyncObserver() const;
+
+  virtual WinCompositorWidget* AsWindows() {
+    return nullptr;
+  }
+  virtual X11CompositorWidget* AsX11() {
+    return nullptr;
+  }
+  virtual AndroidCompositorWidget* AsAndroid() {
+    return nullptr;
+  }
+
+  /**
+   * Return the platform-specific delegate for the widget, if any.
+   */
+  virtual CompositorWidgetDelegate* AsDelegate() {
+    return nullptr;
+  }
+
+protected:
+  virtual ~CompositorWidget();
+
+  // Back buffer of BasicCompositor
+  RefPtr<gfx::DrawTarget> mLastBackBuffer;
+};
+
+} // namespace widget
+} // namespace mozilla
+
+#endif