widget/CompositorWidget.cpp

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #include "CompositorWidget.h"
   6 #include "GLConsts.h"
   7 #include "nsBaseWidget.h"
   8 #include "VsyncDispatcher.h"
   9
  10 namespace mozilla {
  11 namespace widget {
  12
  13 CompositorWidget::CompositorWidget(const layers::CompositorOptions& aOptions)
  14   : mOptions(aOptions)
  15 {
  16 }
  17
  18 CompositorWidget::~CompositorWidget()
  19 {
  20 }
  21
  22 already_AddRefed<gfx::DrawTarget>
  23 CompositorWidget::StartRemoteDrawing()
  24 {
  25   return nullptr;
  26 }
  27
  28 void
  29 CompositorWidget::CleanupRemoteDrawing()
  30 {
  31   mLastBackBuffer = nullptr;
  32 }
  33
  34 already_AddRefed<gfx::DrawTarget>
  35 CompositorWidget::GetBackBufferDrawTarget(gfx::DrawTarget* aScreenTarget,
  36                                           const LayoutDeviceIntRect& aRect,
  37                                           const LayoutDeviceIntRect& aClearRect)
  38 {
  39   MOZ_ASSERT(aScreenTarget);
  40   gfx::SurfaceFormat format =
  41     aScreenTarget->GetFormat() == gfx::SurfaceFormat::B8G8R8X8 ? gfx::SurfaceFormat::B8G8R8X8 : gfx::SurfaceFormat::B8G8R8A8;
  42   gfx::IntSize size = aRect.ToUnknownRect().Size();
  43   gfx::IntSize clientSize(GetClientSize().ToUnknownSize());
  44
  45   RefPtr<gfx::DrawTarget> target;
  46   // Re-use back buffer if possible
  47   if (mLastBackBuffer &&
  48       mLastBackBuffer->GetBackendType() == aScreenTarget->GetBackendType() &&
  49       mLastBackBuffer->GetFormat() == format &&
  50       size <= mLastBackBuffer->GetSize() &&
  51       mLastBackBuffer->GetSize() <= clientSize) {
  52     target = mLastBackBuffer;
  53     target->SetTransform(gfx::Matrix());
  54     if (!aClearRect.IsEmpty()) {
  55       gfx::IntRect clearRect = aClearRect.ToUnknownRect() - aRect.ToUnknownRect().TopLeft();
  56       target->ClearRect(gfx::Rect(clearRect.X(), clearRect.Y(), clearRect.Width(), clearRect.Height()));
  57     }
  58   } else {
  59     target = aScreenTarget->CreateSimilarDrawTarget(size, format);
  60     mLastBackBuffer = target;
  61   }
  62   return target.forget();
  63 }
  64
  65 already_AddRefed<gfx::SourceSurface>
  66 CompositorWidget::EndBackBufferDrawing()
  67 {
  68   RefPtr<gfx::SourceSurface> surface = mLastBackBuffer ? mLastBackBuffer->Snapshot() : nullptr;
  69   return surface.forget();
  70 }
  71
  72 uint32_t
  73 CompositorWidget::GetGLFrameBufferFormat()
  74 {
  75   return LOCAL_GL_RGBA;
  76 }
  77
  78 RefPtr<VsyncObserver>
  79 CompositorWidget::GetVsyncObserver() const
  80 {
  81   // This should only used when the widget is in the GPU process, and should be
  82   // implemented by IPDL-enabled CompositorWidgets.
  83   // GPU process does not have a CompositorVsyncDispatcher.
  84   MOZ_ASSERT_UNREACHABLE("Must be implemented by derived class");
  85   return nullptr;
  86 }
  87
  88 } // namespace widget
  89 } // namespace mozilla