bool GrDrawTarget::setupDstReadIfNecessary(const GrPipelineBuilder& pipelineBuilder,
const GrProcOptInfo& colorPOI,
const GrProcOptInfo& coveragePOI,
GrDeviceCoordTexture* dstCopy,
const SkRect* drawBounds) {
if (!pipelineBuilder.willXPNeedDstCopy(*this->caps(), colorPOI, coveragePOI)) {
return true;
}
SkIRect copyRect;
GrRenderTarget* rt = pipelineBuilder.getRenderTarget();
pipelineBuilder.clip().getConservativeBounds(rt, ©Rect);
if (drawBounds) {
SkIRect drawIBounds;
drawBounds->roundOut(&drawIBounds);
if (!copyRect.intersect(drawIBounds)) {
#ifdef SK_DEBUG
SkDebugf("Missed an early reject. Bailing on draw from setupDstReadIfNecessary.\n");
#endif
return false;
}
} else {
#ifdef SK_DEBUG
//SkDebugf("No dev bounds when dst copy is made.\n");
#endif
}
// MSAA consideration: When there is support for reading MSAA samples in the shader we could
// have per-sample dst values by making the copy multisampled.
GrSurfaceDesc desc;
this->initCopySurfaceDstDesc(rt, &desc);
desc.fWidth = copyRect.width();
desc.fHeight = copyRect.height();
SkAutoTUnref<GrTexture> copy(
fContext->refScratchTexture(desc, GrContext::kApprox_ScratchTexMatch));
if (!copy) {
SkDebugf("Failed to create temporary copy of destination texture.\n");
return false;
}
SkIPoint dstPoint = {0, 0};
if (this->copySurface(copy, rt, copyRect, dstPoint)) {
dstCopy->setTexture(copy);
dstCopy->setOffset(copyRect.fLeft, copyRect.fTop);
return true;
} else {
return false;
}
}
