C++ SkTScopedComPtr::CopyPixels方法代码示例

bool SkImageGeneratorWIC::onGetPixels(const SkImageInfo& info, void* pixels, size_t rowBytes,
        SkPMColor ctable[], int* ctableCount) {
    if (kN32_SkColorType != info.colorType()) {
        return false;
    }

    // Create a format converter.
    SkTScopedComPtr<IWICFormatConverter> formatConverter;
    HRESULT hr = fImagingFactory->CreateFormatConverter(&formatConverter);
    if (FAILED(hr)) {
        return false;
    }

    GUID format = GUID_WICPixelFormat32bppPBGRA;
    if (kUnpremul_SkAlphaType == info.alphaType()) {
        format = GUID_WICPixelFormat32bppBGRA;
    }

    hr = formatConverter->Initialize(fImageSource.get(), format, WICBitmapDitherTypeNone, nullptr,
            0.0, WICBitmapPaletteTypeCustom);
    if (FAILED(hr)) {
        return false;
    }

    // Treat the format converter as an image source.
    SkTScopedComPtr<IWICBitmapSource> formatConverterSrc;
    hr = formatConverter->QueryInterface(IID_PPV_ARGS(&formatConverterSrc));
    if (FAILED(hr)) {
        return false;
    }

    // Set the destination pixels.
    hr = formatConverterSrc->CopyPixels(nullptr, (UINT) rowBytes, (UINT) rowBytes * info.height(),
            (BYTE*) pixels);

    return SUCCEEDED(hr);
}

//.........这里部分代码省略.........
            , IID_PPV_ARGS(&piImagingFactory)
        );
    }
    
    //Convert SkStream to IStream.
    SkTScopedComPtr<IStream> piStream;
    if (SUCCEEDED(hr)) {
        hr = SkIStream::CreateFromSkStream(stream, false, &piStream);
    }
    
    //Make sure we're at the beginning of the stream.
    if (SUCCEEDED(hr)) {
        LARGE_INTEGER liBeginning = { 0 };
        hr = piStream->Seek(liBeginning, STREAM_SEEK_SET, NULL);
    }
    
    //Create the decoder from the stream content.
    SkTScopedComPtr<IWICBitmapDecoder> piBitmapDecoder;
    if (SUCCEEDED(hr)) {
        hr = piImagingFactory->CreateDecoderFromStream(
            piStream.get()                    //Image to be decoded
            , NULL                            //No particular vendor
            , WICDecodeMetadataCacheOnDemand  //Cache metadata when needed
            , &piBitmapDecoder                //Pointer to the decoder
        );
    }
    
    //Get the first frame from the decoder.
    SkTScopedComPtr<IWICBitmapFrameDecode> piBitmapFrameDecode;
    if (SUCCEEDED(hr)) {
        hr = piBitmapDecoder->GetFrame(0, &piBitmapFrameDecode);
    }
    
    //Get the BitmapSource interface of the frame.
    SkTScopedComPtr<IWICBitmapSource> piBitmapSourceOriginal;
    if (SUCCEEDED(hr)) {
        hr = piBitmapFrameDecode->QueryInterface(
            IID_PPV_ARGS(&piBitmapSourceOriginal)
        );
    }
    
    //Get the size of the bitmap.
    UINT width;
    UINT height;
    if (SUCCEEDED(hr)) {
        hr = piBitmapSourceOriginal->GetSize(&width, &height);
    }
    
    //Exit early if we're only looking for the bitmap bounds.
    if (SUCCEEDED(hr)) {
        bm->setConfig(SkBitmap::kARGB_8888_Config, width, height);
        if (SkImageDecoder::kDecodeBounds_Mode == mode) {
            return true;
        }
        if (!this->allocPixelRef(bm, NULL)) {
            return false;
        }
    }
    
    //Create a format converter.
    SkTScopedComPtr<IWICFormatConverter> piFormatConverter;
    if (SUCCEEDED(hr)) {
        hr = piImagingFactory->CreateFormatConverter(&piFormatConverter);
    }
    
    if (SUCCEEDED(hr)) {
        hr = piFormatConverter->Initialize(
            piBitmapSourceOriginal.get()      //Input bitmap to convert
            , GUID_WICPixelFormat32bppPBGRA   //Destination pixel format
            , WICBitmapDitherTypeNone         //Specified dither patterm
            , NULL                            //Specify a particular palette
            , 0.f                             //Alpha threshold
            , WICBitmapPaletteTypeCustom      //Palette translation type
        );
    }
    
    //Get the BitmapSource interface of the format converter.
    SkTScopedComPtr<IWICBitmapSource> piBitmapSourceConverted;
    if (SUCCEEDED(hr)) {
        hr = piFormatConverter->QueryInterface(
            IID_PPV_ARGS(&piBitmapSourceConverted)
        );
    }
    
    //Copy the pixels into the bitmap.
    if (SUCCEEDED(hr)) {
        bm->lockPixels();
        bm->eraseColor(0);
        const int stride = bm->rowBytes();
        hr = piBitmapSourceConverted->CopyPixels(
            NULL,                             //Get all the pixels
            stride,
            stride * height,
            reinterpret_cast<BYTE *>(bm->getPixels())
        );
        bm->unlockPixels();
    }
    
    return SUCCEEDED(hr);
}

//.........这里部分代码省略.........
    }

    if (kDecodeFormat_WICMode == wicMode) {
        SkASSERT(format != nullptr);
        //Get the format
        if (SUCCEEDED(hr)) {
            GUID guidFormat;
            hr = piBitmapDecoder->GetContainerFormat(&guidFormat);
            if (SUCCEEDED(hr)) {
                *format = GuidContainerFormat_to_Format(guidFormat);
                return true;
            }
        }
        return false;
    }

    //Get the first frame from the decoder.
    SkTScopedComPtr<IWICBitmapFrameDecode> piBitmapFrameDecode;
    if (SUCCEEDED(hr)) {
        hr = piBitmapDecoder->GetFrame(0, &piBitmapFrameDecode);
    }

    //Get the BitmapSource interface of the frame.
    SkTScopedComPtr<IWICBitmapSource> piBitmapSourceOriginal;
    if (SUCCEEDED(hr)) {
        hr = piBitmapFrameDecode->QueryInterface(
            IID_PPV_ARGS(&piBitmapSourceOriginal)
        );
    }

    //Get the size of the bitmap.
    UINT width;
    UINT height;
    if (SUCCEEDED(hr)) {
        hr = piBitmapSourceOriginal->GetSize(&width, &height);
    }

    //Exit early if we're only looking for the bitmap bounds.
    if (SUCCEEDED(hr)) {
        bm->setInfo(SkImageInfo::MakeN32Premul(width, height));
        if (kDecodeBounds_WICMode == wicMode) {
            return true;
        }
        if (!this->allocPixelRef(bm, nullptr)) {
            return false;
        }
    }

    //Create a format converter.
    SkTScopedComPtr<IWICFormatConverter> piFormatConverter;
    if (SUCCEEDED(hr)) {
        hr = piImagingFactory->CreateFormatConverter(&piFormatConverter);
    }

    GUID destinationPixelFormat;
    if (this->getRequireUnpremultipliedColors()) {
        destinationPixelFormat = GUID_WICPixelFormat32bppBGRA;
    } else {
        destinationPixelFormat = GUID_WICPixelFormat32bppPBGRA;
    }

    if (SUCCEEDED(hr)) {
        hr = piFormatConverter->Initialize(
            piBitmapSourceOriginal.get()      //Input bitmap to convert
            , destinationPixelFormat          //Destination pixel format
            , WICBitmapDitherTypeNone         //Specified dither patterm
            , nullptr                            //Specify a particular palette
            , 0.f                             //Alpha threshold
            , WICBitmapPaletteTypeCustom      //Palette translation type
        );
    }

    //Get the BitmapSource interface of the format converter.
    SkTScopedComPtr<IWICBitmapSource> piBitmapSourceConverted;
    if (SUCCEEDED(hr)) {
        hr = piFormatConverter->QueryInterface(
            IID_PPV_ARGS(&piBitmapSourceConverted)
        );
    }

    //Copy the pixels into the bitmap.
    if (SUCCEEDED(hr)) {
        SkAutoLockPixels alp(*bm);
        bm->eraseColor(SK_ColorTRANSPARENT);
        const UINT stride = (UINT) bm->rowBytes();
        hr = piBitmapSourceConverted->CopyPixels(
            nullptr,                             //Get all the pixels
            stride,
            stride * height,
            reinterpret_cast<BYTE *>(bm->getPixels())
        );

        // Note: we don't need to premultiply here since we specified PBGRA
        if (SkBitmap::ComputeIsOpaque(*bm)) {
            bm->setAlphaType(kOpaque_SkAlphaType);
        }
    }

    return SUCCEEDED(hr);
}