bool SkImage_Gpu::onReadPixels(const SkImageInfo& info, void* pixels, size_t rowBytes,
int srcX, int srcY, CachingHint) const {
GrPixelConfig config = SkImageInfo2GrPixelConfig(info, *fTexture->getContext()->caps());
uint32_t flags = 0;
if (kUnpremul_SkAlphaType == info.alphaType() && kPremul_SkAlphaType == fAlphaType) {
// let the GPU perform this transformation for us
flags = GrContext::kUnpremul_PixelOpsFlag;
}
if (!fTexture->readPixels(srcX, srcY, info.width(), info.height(), config,
pixels, rowBytes, flags)) {
return false;
}
// do we have to manually fix-up the alpha channel?
// src dst
// unpremul premul fix manually
// premul unpremul done by kUnpremul_PixelOpsFlag
// all other combos need to change.
//
// Should this be handled by Ganesh? todo:?
//
if (kPremul_SkAlphaType == info.alphaType() && kUnpremul_SkAlphaType == fAlphaType) {
apply_premul(info, pixels, rowBytes);
}
return true;
}
bool SkImage_Gpu::onReadPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRB,
int srcX, int srcY, CachingHint) const {
if (!SkImageInfoValidConversion(dstInfo, this->onImageInfo())) {
return false;
}
SkReadPixelsRec rec(dstInfo, dstPixels, dstRB, srcX, srcY);
if (!rec.trim(this->width(), this->height())) {
return false;
}
// TODO: this seems to duplicate code in GrTextureContext::onReadPixels and
// GrRenderTargetContext::onReadPixels
uint32_t flags = 0;
if (kUnpremul_SkAlphaType == rec.fInfo.alphaType() && kPremul_SkAlphaType == fAlphaType) {
// let the GPU perform this transformation for us
flags = GrContextPriv::kUnpremul_PixelOpsFlag;
}
sk_sp<GrSurfaceContext> sContext = fContext->contextPriv().makeWrappedSurfaceContext(
fProxy,
fColorSpace);
if (!sContext) {
return false;
}
if (!sContext->readPixels(rec.fInfo, rec.fPixels, rec.fRowBytes, rec.fX, rec.fY, flags)) {
return false;
}
// do we have to manually fix-up the alpha channel?
// src dst
// unpremul premul fix manually
// premul unpremul done by kUnpremul_PixelOpsFlag
// all other combos need to change.
//
// Should this be handled by Ganesh? todo:?
//
if (kPremul_SkAlphaType == rec.fInfo.alphaType() && kUnpremul_SkAlphaType == fAlphaType) {
apply_premul(rec.fInfo, rec.fPixels, rec.fRowBytes);
}
return true;
}