gecko-dev/gfx/webrender_bindings/RenderCompositor.h

/* -*- 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_RENDERCOMPOSITOR_H
#define MOZILLA_GFX_RENDERCOMPOSITOR_H

#include "mozilla/ipc/FileDescriptor.h"
#include "mozilla/RefPtr.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/webrender/WebRenderTypes.h"
#include "Units.h"

#include "GLTypes.h"

namespace mozilla {

namespace gl {
class GLContext;
}

namespace layers {
class CompositionRecorder;
class SyncObjectHost;
}  // namespace layers

namespace widget {
class CompositorWidget;
}

namespace wr {

class RenderCompositorLayersSWGL;
class RenderCompositorD3D11SWGL;

class RenderCompositor {
 public:
  static UniquePtr<RenderCompositor> Create(
      const RefPtr<widget::CompositorWidget>& aWidget, nsACString& aError);

  RenderCompositor(const RefPtr<widget::CompositorWidget>& aWidget);
  virtual ~RenderCompositor();

  virtual bool BeginFrame() = 0;

  // Optional handler in case the frame was aborted allowing the compositor
  // to clean up relevant resources if required.
  virtual void CancelFrame() {}

  // Called to notify the RenderCompositor that all of the commands for a frame
  // have been pushed to the queue.
  // @return a RenderedFrameId for the frame
  virtual RenderedFrameId EndFrame(
      const nsTArray<DeviceIntRect>& aDirtyRects) = 0;
  // Returns false when waiting gpu tasks is failed.
  // It might happen when rendering context is lost.
  virtual bool WaitForGPU() { return true; }

  // Check for and return the last completed frame.
  // @return the last (highest) completed RenderedFrameId
  virtual RenderedFrameId GetLastCompletedFrameId() {
    return mLatestRenderFrameId.Prev();
  }

  // Update FrameId when WR rendering does not happen.
  virtual RenderedFrameId UpdateFrameId() { return GetNextRenderFrameId(); }

  virtual void Pause() = 0;
  virtual bool Resume() = 0;
  // Called when WR rendering is skipped
  virtual void Update() {}

  virtual gl::GLContext* gl() const { return nullptr; }
  virtual void* swgl() const { return nullptr; }

  virtual bool MakeCurrent();

  virtual bool UseANGLE() const { return false; }

  virtual bool UseDComp() const { return false; }

  virtual bool UseTripleBuffering() const { return false; }

  virtual layers::WebRenderBackend BackendType() const {
    return layers::WebRenderBackend::HARDWARE;
  }
  virtual layers::WebRenderCompositor CompositorType() const {
    return layers::WebRenderCompositor::DRAW;
  }

  virtual RenderCompositorD3D11SWGL* AsRenderCompositorD3D11SWGL() {
    return nullptr;
  }

  virtual RenderCompositorLayersSWGL* AsRenderCompositorLayersSWGL() {
    return nullptr;
  }

  // True if AttachExternalImage supports being used with an external
  // image that maps to a RenderBufferTextureHost
  virtual bool SupportsExternalBufferTextures() const { return false; }

  virtual LayoutDeviceIntSize GetBufferSize() = 0;

  widget::CompositorWidget* GetWidget() const { return mWidget; }

  layers::SyncObjectHost* GetSyncObject() const { return mSyncObject.get(); }

  virtual GLenum IsContextLost(bool aForce);

  virtual bool SupportAsyncScreenshot() { return true; }

  virtual bool ShouldUseNativeCompositor() { return false; }

  // Interface for wr::Compositor
  virtual void CompositorBeginFrame() {}
  virtual void CompositorEndFrame() {}
  virtual void Bind(wr::NativeTileId aId, wr::DeviceIntPoint* aOffset,
                    uint32_t* aFboId, wr::DeviceIntRect aDirtyRect,
                    wr::DeviceIntRect aValidRect) {}
  virtual void Unbind() {}
  virtual bool MapTile(wr::NativeTileId aId, wr::DeviceIntRect aDirtyRect,
                       wr::DeviceIntRect aValidRect, void** aData,
                       int32_t* aStride) {
    return false;
  }
  virtual void UnmapTile() {}
  virtual void CreateSurface(wr::NativeSurfaceId aId,
                             wr::DeviceIntPoint aVirtualOffset,
                             wr::DeviceIntSize aTileSize, bool aIsOpaque) {}
  virtual void CreateExternalSurface(wr::NativeSurfaceId aId, bool aIsOpaque) {}
  virtual void DestroySurface(NativeSurfaceId aId) {}
  virtual void CreateTile(wr::NativeSurfaceId, int32_t aX, int32_t aY) {}
  virtual void DestroyTile(wr::NativeSurfaceId, int32_t aX, int32_t aY) {}
  virtual void AttachExternalImage(wr::NativeSurfaceId aId,
                                   wr::ExternalImageId aExternalImage) {}
  virtual void AddSurface(wr::NativeSurfaceId aId,
                          const wr::CompositorSurfaceTransform& aTransform,
                          wr::DeviceIntRect aClipRect,
                          wr::ImageRendering aImageRendering) {}
  // Called in the middle of a frame after all surfaces have been added but
  // before tiles are updated to signal that early compositing can start
  virtual void StartCompositing(wr::ColorF aClearColor,
                                const wr::DeviceIntRect* aDirtyRects,
                                size_t aNumDirtyRects,
                                const wr::DeviceIntRect* aOpaqueRects,
                                size_t aNumOpaqueRects) {}
  virtual void EnableNativeCompositor(bool aEnable) {}
  virtual void DeInit() {}
  // Overrides any of the default compositor capabilities for behavior this
  // compositor might require.
  virtual void GetCompositorCapabilities(CompositorCapabilities* aCaps);

  // Interface for partial present
  virtual bool UsePartialPresent() { return false; }
  virtual bool RequestFullRender() { return false; }
  virtual uint32_t GetMaxPartialPresentRects() { return 0; }
  virtual bool ShouldDrawPreviousPartialPresentRegions() { return false; }
  // Returns the age of the current backbuffer., This should be used, if
  // ShouldDrawPreviousPartialPresentRegions() returns true, to determine the
  // region which must be rendered in addition to the current frame's dirty
  // rect.
  virtual size_t GetBufferAge() const { return 0; }
  // Allows webrender to specify the total region that will be rendered to this
  // frame, ie the frame's dirty region and some previous frames' dirty regions,
  // if applicable (calculated using the buffer age). Must be called before
  // anything has been rendered to the main framebuffer.
  virtual void SetBufferDamageRegion(const wr::DeviceIntRect* aRects,
                                     size_t aNumRects) {}

  // Whether the surface origin is top-left.
  virtual bool SurfaceOriginIsTopLeft() { return false; }

  // Does readback if wr_renderer_readback() could not get correct WR rendered
  // result. It could happen when WebRender renders to multiple overlay layers.
  virtual bool MaybeReadback(const gfx::IntSize& aReadbackSize,
                             const wr::ImageFormat& aReadbackFormat,
                             const Range<uint8_t>& aReadbackBuffer,
                             bool* aNeedsYFlip) {
    return false;
  }
  virtual void MaybeRequestAllowFrameRecording(bool aWillRecord) {}
  virtual bool MaybeRecordFrame(layers::CompositionRecorder& aRecorder) {
    return false;
  }
  virtual bool MaybeGrabScreenshot(const gfx::IntSize& aWindowSize) {
    return false;
  }
  virtual bool MaybeProcessScreenshotQueue() { return false; }

  // Returns FileDescriptor of release fence.
  // Release fence is a fence that is used for waiting until usage/composite of
  // AHardwareBuffer is ended. The fence is delivered to client side via
  // ImageBridge. It is used only on android.
  virtual ipc::FileDescriptor GetAndResetReleaseFence() {
    return ipc::FileDescriptor();
  }

  virtual bool IsPaused() { return false; }

 protected:
  // We default this to 2, so that mLatestRenderFrameId.Prev() is always valid.
  RenderedFrameId mLatestRenderFrameId = RenderedFrameId{2};
  RenderedFrameId GetNextRenderFrameId() {
    mLatestRenderFrameId = mLatestRenderFrameId.Next();
    return mLatestRenderFrameId;
  }

  RefPtr<widget::CompositorWidget> mWidget;
  RefPtr<layers::SyncObjectHost> mSyncObject;
};

}  // namespace wr
}  // namespace mozilla

#endif