这个问题与this非常相似,但那个问题还没有得到解答。我的问题是,我有一个来自d2dfactory-> CreateDxgiSurfaceRenderTarget()的D2D DXGI RenderTarget,并且我想使用WIC将其内容保存为图像文件。我只是读this和this,所以它在我看来,我不能只是在WIC渲染目标上创建一个ID2D1Bitmap,并使用ID2D1Bitmap :: CopyFromRenderTarget()从我想保存的输入渲染目标中复制,因为它们正在使用不同的资源。因此,这里是我想出了使用ID2D1RenderTarget :: CreateSharedBitmap():Direct2D:如何将ID2D1RenderTarget的内容保存到图像文件?
HRESULT SaveRenderTargetToFile(
ID2D1RenderTarget* pRTSrc,
LPCWSTR uri
)
{
HRESULT hr = S_OK;
ComPtr<IWICBitmap> spWICBitmap;
ComPtr<ID2D1RenderTarget> spRT;
ComPtr<IWICBitmapEncoder> spEncoder;
ComPtr<IWICBitmapFrameEncode> spFrameEncode;
ComPtr<IWICStream> spStream;
//
// Create WIC bitmap to save and associated render target
//
UINT bitmapWidth = static_cast<UINT>(pRTSrc->GetSize().width + .5f);
UINT bitmapHeight = static_cast<UINT>(pRTSrc->GetSize().height + .5f);
HR(m_spWICFactory->CreateBitmap(
bitmapWidth,
bitmapHeight,
GUID_WICPixelFormat32bppPBGRA,
WICBitmapCacheOnLoad,
&spWICBitmap
));
D2D1_RENDER_TARGET_PROPERTIES prop = D2D1::RenderTargetProperties();
prop.pixelFormat = D2D1::PixelFormat(
DXGI_FORMAT_B8G8R8A8_UNORM,
D2D1_ALPHA_MODE_PREMULTIPLIED
);
prop.type = D2D1_RENDER_TARGET_TYPE_DEFAULT;
prop.usage = D2D1_RENDER_TARGET_USAGE_NONE;
HR(m_spD2D1Factory->CreateWicBitmapRenderTarget(
spWICBitmap,
prop,
&spRT
));
//
// Create a shared bitmap from this RenderTarget
//
ComPtr<ID2D1Bitmap> spBitmap;
D2D1_BITMAP_PROPERTIES bp = D2D1::BitmapProperties();
bp.pixelFormat = prop.pixelFormat;
HR(spRT->CreateSharedBitmap(
__uuidof(IWICBitmap),
static_cast<void*>(spWICBitmap.GetRawPointer()),
&bp,
&spBitmap
)); // <------------------------- This fails with E_INVALIDARG
//
// Copy the source RenderTarget to this bitmap
//
HR(spBitmap->CopyFromRenderTarget(nullptr, pRTSrc, nullptr));
//
// Draw this bitmap to the output render target
//
spRT->BeginDraw();
spRT->Clear(D2D1::ColorF(D2D1::ColorF::GreenYellow));
spRT->DrawBitmap(spBitmap);
HR(spRT->EndDraw());
//
// Save image to file
//
HR(m_spWICFactory->CreateStream(&spStream));
WICPixelFormatGUID format = GUID_WICPixelFormat32bppPBGRA;
HR(spStream->InitializeFromFilename(uri, GENERIC_WRITE));
HR(m_spWICFactory->CreateEncoder(GUID_ContainerFormatPng, nullptr, &spEncoder));
HR(spEncoder->Initialize(spStream, WICBitmapEncoderNoCache));
HR(spEncoder->CreateNewFrame(&spFrameEncode, nullptr));
HR(spFrameEncode->Initialize(nullptr));
HR(spFrameEncode->SetSize(bitmapWidth, bitmapHeight));
HR(spFrameEncode->SetPixelFormat(&format));
HR(spFrameEncode->WriteSource(spWICBitmap, nullptr));
HR(spFrameEncode->Commit());
HR(spEncoder->Commit());
HR(spStream->Commit(STGC_DEFAULT));
done:
return hr;
}
任何问题与此代码? (我确定有很多:))MSDN上的某处表示WIC渲染目标只支持软件模式,而DXGI渲染目标只支持硬件模式。这是上述对CreateSharedBitmap()的调用失败的原因吗?那么我应该如何将DXGI曲面内容保存到使用D2D的图像文件中?