gecko-dev/widget/CompositorWidget.cpp
Lee Salzman 988104567f Bug 1689245 - replace CompositorWidget::ClearBeforePaint with GetTransparentRegion. r=mattwoodrow CLOSED TREE
ClearBeforePaint put the responsibility of clearing the current frame's DrawTarget
onto the widget. This doesn't compose well with WR RenderCompositor that may do
their own internal clearing. Instead, replace this with a GetTransparentRegion API
that can be used by RenderCompositors to limit where they clear so that they are
now fully responsible for clearing.

Differential Revision: https://phabricator.services.mozilla.com/D103253
2021-01-28 09:12:40 +00:00

78 lines
2.8 KiB
C++

/* 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(const layers::CompositorOptions& aOptions)
: mOptions(aOptions) {}
CompositorWidget::~CompositorWidget() = default;
already_AddRefed<gfx::DrawTarget> CompositorWidget::StartRemoteDrawing() {
return nullptr;
}
void CompositorWidget::CleanupRemoteDrawing() { mLastBackBuffer = nullptr; }
already_AddRefed<gfx::DrawTarget> CompositorWidget::GetBackBufferDrawTarget(
gfx::DrawTarget* aScreenTarget, const gfx::IntRect& aRect,
bool* aOutIsCleared) {
MOZ_ASSERT(aScreenTarget);
gfx::SurfaceFormat format =
aScreenTarget->GetFormat() == gfx::SurfaceFormat::B8G8R8X8
? gfx::SurfaceFormat::B8G8R8X8
: gfx::SurfaceFormat::B8G8R8A8;
gfx::IntSize size = aRect.Size();
gfx::IntSize clientSize = Max(size, GetClientSize().ToUnknownSize());
*aOutIsCleared = false;
// Re-use back buffer if possible
if (!mLastBackBuffer ||
mLastBackBuffer->GetBackendType() != aScreenTarget->GetBackendType() ||
mLastBackBuffer->GetFormat() != format ||
mLastBackBuffer->GetSize() != clientSize) {
mLastBackBuffer =
aScreenTarget->CreateSimilarDrawTarget(clientSize, format);
*aOutIsCleared = true;
}
return do_AddRef(mLastBackBuffer);
}
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;
}
LayoutDeviceIntRegion CompositorWidget::GetTransparentRegion() {
// By default, we check the transparency mode to determine if the widget is
// transparent, and if so, designate the entire widget drawing area as
// transparent. Widgets wanting more complex transparency region determination
// should override this method.
auto* widget = RealWidget();
if (!widget || widget->GetTransparencyMode() != eTransparencyOpaque) {
return LayoutDeviceIntRect(LayoutDeviceIntPoint(0, 0), GetClientSize());
}
return LayoutDeviceIntRegion();
}
} // namespace widget
} // namespace mozilla