widget/CompositorWidget.cpp
author Chris H-C <chutten@mozilla.com>
Mon, 04 Jul 2016 11:16:05 -0400
changeset 312997 df28918fe2361f0b54ca9ce4773a29c4c0675d06
parent 305742 3fdb8ca3e6ffbd310daf342eb8febb1c17938dd0
permissions -rw-r--r--
bug 1218576 - Support remote accumulation via JS histograms. r=gfritzsche The JS histograms, too, need to dispatch their accumulations from child to parent. JSHistograms_Add now only supports histograms that are in gHistogramsMap or that were created in the parent process. After bug 1288745, maybe we'll be able to change this to be less convoluted. MozReview-Commit-ID: 3qTH89YKbGP

/* 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/. */

#include "CompositorWidget.h"
#include "GLConsts.h"
#include "nsBaseWidget.h"
#include "VsyncDispatcher.h"

namespace mozilla {
namespace widget {

CompositorWidget::~CompositorWidget()
{
}

already_AddRefed<gfx::DrawTarget>
CompositorWidget::StartRemoteDrawing()
{
  return nullptr;
}

void
CompositorWidget::CleanupRemoteDrawing()
{
  mLastBackBuffer = nullptr;
}

already_AddRefed<gfx::DrawTarget>
CompositorWidget::GetBackBufferDrawTarget(gfx::DrawTarget* aScreenTarget,
                                          const LayoutDeviceIntRect& aRect,
                                          const LayoutDeviceIntRect& aClearRect)
{
  MOZ_ASSERT(aScreenTarget);
  gfx::SurfaceFormat format =
    aScreenTarget->GetFormat() == gfx::SurfaceFormat::B8G8R8X8 ? gfx::SurfaceFormat::B8G8R8X8 : gfx::SurfaceFormat::B8G8R8A8;
  gfx::IntSize size = aRect.ToUnknownRect().Size();
  gfx::IntSize clientSize(GetClientSize().ToUnknownSize());

  RefPtr<gfx::DrawTarget> target;
  // Re-use back buffer if possible
  if (mLastBackBuffer &&
      mLastBackBuffer->GetBackendType() == aScreenTarget->GetBackendType() &&
      mLastBackBuffer->GetFormat() == format &&
      size <= mLastBackBuffer->GetSize() &&
      mLastBackBuffer->GetSize() <= clientSize) {
    target = mLastBackBuffer;
    target->SetTransform(gfx::Matrix());
    if (!aClearRect.IsEmpty()) {
      gfx::IntRect clearRect = aClearRect.ToUnknownRect() - aRect.ToUnknownRect().TopLeft();
      target->ClearRect(gfx::Rect(clearRect.x, clearRect.y, clearRect.width, clearRect.height));
    }
  } else {
    target = aScreenTarget->CreateSimilarDrawTarget(size, format);
    mLastBackBuffer = target;
  }
  return target.forget();
}

already_AddRefed<gfx::SourceSurface>
CompositorWidget::EndBackBufferDrawing()
{
  RefPtr<gfx::SourceSurface> surface = mLastBackBuffer ? mLastBackBuffer->Snapshot() : nullptr;
  return surface.forget();
}

uint32_t
CompositorWidget::GetGLFrameBufferFormat()
{
  return LOCAL_GL_RGBA;
}

RefPtr<VsyncObserver>
CompositorWidget::GetVsyncObserver() const
{
  // This should only used when the widget is in the GPU process, and should be
  // implemented by IPDL-enabled CompositorWidgets.
  // GPU process does not have a CompositorVsyncDispatcher.
  MOZ_ASSERT_UNREACHABLE("Must be implemented by derived class");
  return nullptr;
}

} // namespace widget
} // namespace mozilla