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 CompositorWidget::~CompositorWidget() = default;
  17
  18 already_AddRefed<gfx::DrawTarget> CompositorWidget::StartRemoteDrawing() {
  19   return nullptr;
  20 }
  21
  22 void CompositorWidget::CleanupRemoteDrawing() { mLastBackBuffer = nullptr; }
  23
  24 already_AddRefed<gfx::DrawTarget> CompositorWidget::GetBackBufferDrawTarget(
  25     gfx::DrawTarget* aScreenTarget, const gfx::IntRect& aRect,
  26     bool* aOutIsCleared) {
  27   MOZ_ASSERT(aScreenTarget);
  28   gfx::SurfaceFormat format =
  29       aScreenTarget->GetFormat() == gfx::SurfaceFormat::B8G8R8X8
  30           ? gfx::SurfaceFormat::B8G8R8X8
  31           : gfx::SurfaceFormat::B8G8R8A8;
  32   gfx::IntSize size = aRect.Size();
  33   gfx::IntSize clientSize = Max(size, GetClientSize().ToUnknownSize());
  34
  35   *aOutIsCleared = false;
  36   // Re-use back buffer if possible
  37   if (!mLastBackBuffer ||
  38       mLastBackBuffer->GetBackendType() != aScreenTarget->GetBackendType() ||
  39       mLastBackBuffer->GetFormat() != format ||
  40       mLastBackBuffer->GetSize() != clientSize) {
  41     mLastBackBuffer =
  42         aScreenTarget->CreateSimilarDrawTarget(clientSize, format);
  43     *aOutIsCleared = true;
  44   }
  45   return do_AddRef(mLastBackBuffer);
  46 }
  47
  48 already_AddRefed<gfx::SourceSurface> CompositorWidget::EndBackBufferDrawing() {
  49   RefPtr<gfx::SourceSurface> surface =
  50       mLastBackBuffer ? mLastBackBuffer->Snapshot() : nullptr;
  51   return surface.forget();
  52 }
  53
  54 uint32_t CompositorWidget::GetGLFrameBufferFormat() { return LOCAL_GL_RGBA; }
  55
  56 RefPtr<VsyncObserver> CompositorWidget::GetVsyncObserver() const {
  57   // This should only used when the widget is in the GPU process, and should be
  58   // implemented by IPDL-enabled CompositorWidgets.
  59   // GPU process does not have a CompositorVsyncDispatcher.
  60   MOZ_ASSERT_UNREACHABLE("Must be implemented by derived class");
  61   return nullptr;
  62 }
  63
  64 LayoutDeviceIntRegion CompositorWidget::GetTransparentRegion() {
  65   // By default, we check the transparency mode to determine if the widget is
  66   // transparent, and if so, designate the entire widget drawing area as
  67   // transparent. Widgets wanting more complex transparency region determination
  68   // should override this method.
  69   auto* widget = RealWidget();
  70   if (!widget || widget->GetTransparencyMode() != TransparencyMode::Opaque ||
  71       widget->WidgetPaintsBackground()) {
  72     return LayoutDeviceIntRect(LayoutDeviceIntPoint(0, 0), GetClientSize());
  73   }
  74   return LayoutDeviceIntRegion();
  75 }
  76
  77 }  // namespace widget
  78 }  // namespace mozilla