already_AddRefed<DrawTarget>
gfxAlphaBoxBlur::InitDrawTarget(const DrawTarget* aReferenceDT,
const Rect& aRect,
const IntSize& aSpreadRadius,
const IntSize& aBlurRadius,
const Rect* aDirtyRect,
const Rect* aSkipRect)
{
mBlur.Init(aRect, aSpreadRadius, aBlurRadius, aDirtyRect, aSkipRect);
size_t blurDataSize = mBlur.GetSurfaceAllocationSize();
if (blurDataSize == 0) {
return nullptr;
}
BackendType backend = aReferenceDT->GetBackendType();
// Check if the backend has an accelerated DrawSurfaceWithShadow.
// Currently, only D2D1.1 supports this.
// Otherwise, DrawSurfaceWithShadow only supports square blurs without spread.
if (aBlurRadius.IsSquare() && aSpreadRadius.IsEmpty() &&
backend == BackendType::DIRECT2D1_1) {
mAccelerated = true;
mDrawTarget =
aReferenceDT->CreateShadowDrawTarget(mBlur.GetSize(),
SurfaceFormat::A8,
AlphaBoxBlur::CalculateBlurSigma(aBlurRadius.width));
} else {
// Make an alpha-only surface to draw on. We will play with the data after
// everything is drawn to create a blur effect.
mData = static_cast<uint8_t*>(calloc(1, blurDataSize));
if (!mData) {
return nullptr;
}
mDrawTarget =
Factory::DoesBackendSupportDataDrawtarget(backend) ?
Factory::CreateDrawTargetForData(backend,
mData,
mBlur.GetSize(),
mBlur.GetStride(),
SurfaceFormat::A8) :
gfxPlatform::CreateDrawTargetForData(mData,
mBlur.GetSize(),
mBlur.GetStride(),
SurfaceFormat::A8);
}
if (!mDrawTarget || !mDrawTarget->IsValid()) {
return nullptr;
}
mDrawTarget->SetTransform(Matrix::Translation(-mBlur.GetRect().TopLeft()));
return do_AddRef(mDrawTarget);
}
already_AddRefed<DrawTarget>
gfxAlphaBoxBlur::InitDrawTarget(const DrawTarget* aReferenceDT,
const Rect& aRect,
const IntSize& aSpreadRadius,
const IntSize& aBlurRadius,
const Rect* aDirtyRect,
const Rect* aSkipRect,
bool aUseHardwareAccel)
{
mBlur.Init(aRect, aSpreadRadius, aBlurRadius, aDirtyRect, aSkipRect);
size_t blurDataSize = mBlur.GetSurfaceAllocationSize();
if (blurDataSize == 0) {
return nullptr;
}
BackendType backend = aReferenceDT->GetBackendType();
// Check if the backend has an accelerated DrawSurfaceWithShadow.
// Currently, only D2D1.1 supports this.
// Otherwise, DrawSurfaceWithShadow only supports square blurs without spread.
// When blurring small draw targets such as short spans text, the cost of
// creating and flushing an accelerated draw target may exceed the speedup
// gained from the faster blur. It's up to the users of this blur
// to determine whether they want to use hardware acceleration.
if (aBlurRadius.IsSquare() && aSpreadRadius.IsEmpty() &&
aUseHardwareAccel &&
backend == BackendType::DIRECT2D1_1) {
mAccelerated = true;
mDrawTarget =
aReferenceDT->CreateShadowDrawTarget(mBlur.GetSize(),
SurfaceFormat::A8,
AlphaBoxBlur::CalculateBlurSigma(aBlurRadius.width));
} else {
// Make an alpha-only surface to draw on. We will play with the data after
// everything is drawn to create a blur effect.
// This will be freed when the DrawTarget dies
mData = static_cast<uint8_t*>(calloc(1, blurDataSize));
if (!mData) {
return nullptr;
}
mDrawTarget =
Factory::DoesBackendSupportDataDrawtarget(backend) ?
Factory::CreateDrawTargetForData(backend,
mData,
mBlur.GetSize(),
mBlur.GetStride(),
SurfaceFormat::A8) :
gfxPlatform::CreateDrawTargetForData(mData,
mBlur.GetSize(),
mBlur.GetStride(),
SurfaceFormat::A8);
}
if (!mDrawTarget || !mDrawTarget->IsValid()) {
if (mData) {
free(mData);
}
return nullptr;
}
if (mData) {
mDrawTarget->AddUserData(reinterpret_cast<UserDataKey*>(mDrawTarget.get()),
mData,
free);
}
mDrawTarget->SetTransform(Matrix::Translation(-mBlur.GetRect().TopLeft()));
return do_AddRef(mDrawTarget);
}