gecko-dev/gfx/layers/CopyableCanvasRenderer.cpp
2019-03-01 22:37:37 +00:00

178 lines
5.4 KiB
C++

/* -*- 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/. */
#include "CopyableCanvasRenderer.h"
#include "BasicLayersImpl.h" // for FillWithMask, etc
#include "GLContext.h" // for GLContext
#include "GLScreenBuffer.h" // for GLScreenBuffer
#include "SharedSurface.h" // for SharedSurface
#include "SharedSurfaceGL.h" // for SharedSurface
#include "gfxPattern.h" // for gfxPattern, etc
#include "gfxPlatform.h" // for gfxPlatform, gfxImageFormat
#include "gfxRect.h" // for gfxRect
#include "gfxUtils.h" // for gfxUtils
#include "gfx2DGlue.h" // for thebes --> moz2d transition
#include "mozilla/gfx/BaseSize.h" // for BaseSize
#include "mozilla/gfx/Tools.h"
#include "mozilla/gfx/Point.h" // for IntSize
#include "mozilla/layers/AsyncCanvasRenderer.h"
#include "mozilla/layers/PersistentBufferProvider.h"
#include "nsDebug.h" // for NS_ASSERTION, NS_WARNING, etc
#include "nsISupportsImpl.h" // for gfxContext::AddRef, etc
#include "nsRect.h" // for mozilla::gfx::IntRect
#include "gfxUtils.h"
#include "client/TextureClientSharedSurface.h"
namespace mozilla {
namespace layers {
using namespace mozilla::gfx;
using namespace mozilla::gl;
CopyableCanvasRenderer::CopyableCanvasRenderer()
: mGLContext(nullptr),
mBufferProvider(nullptr),
mAsyncRenderer(nullptr),
mIsAlphaPremultiplied(true),
mOriginPos(gl::OriginPos::TopLeft),
mOpaque(true),
mCachedTempSurface(nullptr) {
MOZ_COUNT_CTOR(CopyableCanvasRenderer);
}
CopyableCanvasRenderer::~CopyableCanvasRenderer() {
Destroy();
MOZ_COUNT_DTOR(CopyableCanvasRenderer);
}
void CopyableCanvasRenderer::Initialize(const CanvasInitializeData& aData) {
CanvasRenderer::Initialize(aData);
if (aData.mGLContext) {
if (aData.mGLContext->IsDestroyed()) {
return;
}
mGLContext = aData.mGLContext;
mIsAlphaPremultiplied = aData.mIsGLAlphaPremult;
mOriginPos = gl::OriginPos::BottomLeft;
MOZ_ASSERT(mGLContext->IsOffscreen(), "canvas gl context isn't offscreen");
} else if (aData.mBufferProvider) {
mBufferProvider = aData.mBufferProvider;
} else if (aData.mRenderer) {
mAsyncRenderer = aData.mRenderer;
mOriginPos = gl::OriginPos::BottomLeft;
}
mOpaque = !aData.mHasAlpha;
}
bool CopyableCanvasRenderer::IsDataValid(const CanvasInitializeData& aData) {
return mGLContext == aData.mGLContext &&
mBufferProvider == aData.mBufferProvider;
}
void CopyableCanvasRenderer::ClearCachedResources() {
SetDirty();
if (mBufferProvider) {
mBufferProvider->ClearCachedResources();
}
mCachedTempSurface = nullptr;
}
void CopyableCanvasRenderer::Destroy() {
if (mBufferProvider) {
mBufferProvider->ClearCachedResources();
}
mBufferProvider = nullptr;
mCachedTempSurface = nullptr;
}
already_AddRefed<SourceSurface> CopyableCanvasRenderer::ReadbackSurface() {
struct ScopedFireTransactionCallback {
explicit ScopedFireTransactionCallback(CopyableCanvasRenderer* aRenderer)
: mRenderer(aRenderer) {
mRenderer->FirePreTransactionCallback();
}
~ScopedFireTransactionCallback() {
mRenderer->FireDidTransactionCallback();
}
CopyableCanvasRenderer* mRenderer;
};
ScopedFireTransactionCallback callback(this);
if (mAsyncRenderer) {
MOZ_ASSERT(!mBufferProvider);
MOZ_ASSERT(!mGLContext);
return mAsyncRenderer->GetSurface();
}
if (!mGLContext) {
return nullptr;
}
SharedSurface* frontbuffer = nullptr;
if (mGLContext->Screen()) {
const auto& front = mGLContext->Screen()->Front();
if (front) {
frontbuffer = front->Surf();
}
}
if (!frontbuffer) {
NS_WARNING("Null frame received.");
return nullptr;
}
IntSize readSize(frontbuffer->mSize);
SurfaceFormat format = frontbuffer->mHasAlpha ? SurfaceFormat::B8G8R8A8
: SurfaceFormat::B8G8R8X8;
bool needsPremult = frontbuffer->mHasAlpha && !mIsAlphaPremultiplied;
RefPtr<DataSourceSurface> resultSurf = GetTempSurface(readSize, format);
// There will already be a warning from inside of GetTempSurface, but
// it doesn't hurt to complain:
if (NS_WARN_IF(!resultSurf)) {
return nullptr;
}
// Readback handles Flush/MarkDirty.
if (!mGLContext->Readback(frontbuffer, resultSurf)) {
NS_WARNING("Failed to read back canvas surface.");
return nullptr;
}
if (needsPremult) {
gfxUtils::PremultiplyDataSurface(resultSurf, resultSurf);
}
MOZ_ASSERT(resultSurf);
return resultSurf.forget();
}
DataSourceSurface* CopyableCanvasRenderer::GetTempSurface(
const IntSize& aSize, const SurfaceFormat aFormat) {
if (!mCachedTempSurface || aSize != mCachedTempSurface->GetSize() ||
aFormat != mCachedTempSurface->GetFormat()) {
// Create a surface aligned to 8 bytes since that's the highest alignment
// WebGL can handle.
uint32_t stride = GetAlignedStride<8>(aSize.width, BytesPerPixel(aFormat));
mCachedTempSurface =
Factory::CreateDataSourceSurfaceWithStride(aSize, aFormat, stride);
}
return mCachedTempSurface;
}
} // namespace layers
} // namespace mozilla