Directx10翻转纹理水平/垂直

Question

正如我在标题中提到的，你知道如何水平/垂直翻转 ID3D10Texture2D 对象吗？

我使用此代码截取屏幕并将其保存到文件中。

ID3D10Resource *backbufferRes;
renderTargetView->GetResource(&backbufferRes);
ID3D10Texture2D *mRenderedTexture;

// Create our texture
D3D10_TEXTURE2D_DESC texDesc;
texDesc.ArraySize = 1;
texDesc.BindFlags = 0;
texDesc.CPUAccessFlags = 0;
texDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
texDesc.Width = 640;  // must be same as backbuffer
texDesc.Height = 480; // must be same as backbuffer
texDesc.MipLevels = 1;
texDesc.MiscFlags = 0;
texDesc.SampleDesc.Count = 1;
texDesc.SampleDesc.Quality = 0;
texDesc.Usage = D3D10_USAGE_DEFAULT;

d3d10Device->CreateTexture2D(&texDesc, 0, &mRenderedTexture); 

d3d10Device->CopyResource(mRenderedTexture, backbufferRes);

D3DX10FilterTexture(mRenderedTexture, 0, D3DX10_FILTER_MIRROR_U);

D3DX10SaveTextureToFile(mRenderedTexture, D3DX10_IFF_PNG, L"test.png");

D3DX10FilterTexture(mRenderedTexture, 0, D3DX10_FILTER_MIRROR_U);线条不反映我的纹理。有什么建议 ？

Answer 1

在您的着色器中执行 1-u 水平翻转或 1-v 垂直翻转。

编辑：如果您实际上没有进行任何渲染，那么还有更好的方法来进行图像处理。但是，如果您想手动执行此操作，则必须使用地图并自己翻转数据。

您可以这样做（代码未经测试，请原谅任何编译错误）：

D3D10Resource *backbufferRes;
renderTargetView->GetResource(&backbufferRes);
ID3D10Texture2D *mRenderedTexture;

// Create our texture
D3D10_TEXTURE2D_DESC texDesc;
texDesc.ArraySize = 1;
texDesc.BindFlags = 0;
texDesc.CPUAccessFlags = 0;
texDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
texDesc.Width = 640;  // must be same as backbuffer
texDesc.Height = 480; // must be same as backbuffer
texDesc.MipLevels = 1;
texDesc.MiscFlags = 0;
texDesc.SampleDesc.Count = 1;
texDesc.SampleDesc.Quality = 0;
texDesc.Usage = D3D10_USAGE_DEFAULT;

d3d10Device->CreateTexture2D(&texDesc, 0, &mRenderedTexture); 

d3d10Device->CopyResource(mRenderedTexture, backbufferRes);

D3D10_MAPPED_TEXTURE2D d3d10MT = { 0 };
mRenderedTexture->Map( 0, D3D10_MAP_READ_WRITE, 0, &d3d10MT );

unsigned int* pPix = (unsigned int)d3d10MT.pData;

int rows    = 0;
int rowsMax = height;
while( rows < rowsMax )
{
    unsigned int* pRowStart = pPix + (rows * width);
    unsigned int* pRowEnd   = pRowStart + width;
    std::reverse( pRowStart, pRowEnd );
    rows++;
}

mRenderedTexture->Unmap();

D3DX10SaveTextureToFile(mRenderedTexture, D3DX10_IFF_PNG, L"test.png");

来自文档顺便说一句：

D3DX10_FILTER_MIRROR_U 像素离开纹理边缘 u 轴应该是镜像的，而不是包裹的。

因此，当您过滤图像时，仅计算边缘周围的像素。