我正在开发一个“3D桌面”DirectX应用程序，需要在DirectX（11）上将桌面窗口（例如“计算器”）的当前内容显示为2D纹理，放置在矩形表面上。我已经接近成功，但是在截图BMP-> Texture2D步骤中遇到了困难。 我已经成功地实现了截图-> HBITMAP和DDS文件->渲染纹理，但无法完成截图->渲染纹理的步骤。
到目前为止，我已经完成了“捕获窗口截图”的部分。
采样器状态（默认为线性）是：
到目前为止，我已经完成了“捕获窗口截图”的部分。
RECT user_window_rectangle;
HWND user_window = FindWindow(NULL, TEXT("Calculator"));
GetClientRect(user_window, &user_window_rectangle);
HDC hdcScreen = GetDC(NULL);
HDC hdc = CreateCompatibleDC(hdcScreen);
UINT screenshot_width = user_window_rectangle.right - user_window_rectangle.left;
UINT screenshot_height = user_window_rectangle.bottom - user_window_rectangle.top;
hbmp = CreateCompatibleBitmap(hdcScreen, screenshot_width, screenshot_height);
SelectObject(hdc, hbmp);
PrintWindow(user_window, hdc, PW_CLIENTONLY);
目前，我已经有了由HBITMAP hbmp引用的窗口位图。
我的代码也能够在DirectX/3D矩形上呈现DDS文件作为纹理：
ID3D11Device *dev;
ID3D11DeviceContext *dev_context;
...
dev_context->PSSetShaderResources(0, 1, &shader_resource_view);
dev_context->PSSetSamplers(0, 1, &tex_sampler_state);
...
DirectX::TexMetadata tex_metadata;
DirectX::ScratchImage image;
hr = LoadFromDDSFile(L"Earth.dds", DirectX::DDS_FLAGS_NONE, &tex_metadata, image);
hr = CreateShaderResourceView(dev, image.GetImages(), image.GetImageCount(), tex_metadata, &shader_resource_view);
像素着色器是：
Texture2D ObjTexture
SamplerState ObjSamplerState
float4 PShader(float4 pos : SV_POSITION, float4 color : COLOR, float2 tex : TEXCOORD) : SV_TARGET\
{
return ObjTexture.Sample( ObjSamplerState, tex );
}
采样器状态（默认为线性）是：
D3D11_SAMPLER_DESC sampler_desc;
ZeroMemory(&sampler_desc, sizeof(sampler_desc));
sampler_desc.AddressU = D3D11_TEXTURE_ADDRESS_WRAP;
sampler_desc.AddressV = D3D11_TEXTURE_ADDRESS_WRAP;
sampler_desc.AddressW = D3D11_TEXTURE_ADDRESS_WRAP;
sampler_desc.MinLOD = 0;
sampler_desc.MaxLOD = D3D11_FLOAT32_MAX;
hr = dev->CreateSamplerState(&sampler_desc, &tex_sampler_state);
问题：如何用一个等效的方法替换LoadFromDDSFile位，使其从Windows截屏中获取HBITMAP，并将其转换为ObjTexture加载到图形卡中？
以下是我最好的尝试，将屏幕截图HBITMAP hbmp与着色器资源screenshot_texture连接起来，但它会导致来自图形驱动程序的内存访问冲突（我认为是由于我的"data.pSysmem = &bmp.bmBits"引起的，但实际上我毫无头绪）：
GetObject(hbmp, sizeof(BITMAP), (LPSTR)&bmp)
D3D11_TEXTURE2D_DESC screenshot_desc = CD3D11_TEXTURE2D_DESC(DXGI_FORMAT_R8G8B8A8_UNORM, bmp.bmWidth, bmp.bmHeight, 1,
1,
D3D11_BIND_SHADER_RESOURCE
);
int bytes_per_pixel = 4;
D3D11_SUBRESOURCE_DATA data;
ZeroMemory(&data, sizeof(D3D11_SUBRESOURCE_DATA));
data.pSysMem = &bmp.bmBits; //pixel buffer
data.SysMemPitch = bytes_per_pixel * bmp.bmWidth;// line size in byte
data.SysMemSlicePitch = bytes_per_pixel * bmp.bmWidth * bmp.bmHeight;// total buffer size in byte
hr = dev->CreateTexture2D(
&screenshot_desc, //texture format
&data, // pixel buffer use to fill the texture
&screenshot_texture // created texture
);
:::::::::::::::::::::::::解决方案::::::::::::::::::::::::::::::::::::::::::
主要问题是直接使用&bmp.bmBits作为像素缓冲区会在图形驱动程序中引起内存冲突-这可以通过使用'malloc'来分配一个适当大小的内存块来存储像素数据来解决。感谢Chuck Walbourn帮助我摸索出像素数据实际上是如何存储的（默认情况下实际上是32位/像素）。仍然有可能/很可能一些代码依赖于幸运来正确读取像素数据，但是随着Chuck的输入，它已经得到了改进。
我的基本技术是;
- FindWindow以获取桌面上的客户端窗口
- CreateCompatibleBitmap和SelectObject和PrintWindow以获取HBITMAP以进行快照
- malloc以分配正确数量的空间给(byte*)像素缓冲区
- GetDIBits将(byte*)像素缓冲区从HBITMAP填充
- CreateTexture2D建立纹理缓冲区
- CreateShaderResourceView将纹理映射到图形像素着色器
因此，截取Windows桌面窗口并将其作为纹理传递给direct3d应用程序的工作代码是：
RECT user_window_rectangle;
HWND user_window = FindWindow(NULL, TEXT("Calculator")); //the window can't be min
if (user_window == NULL)
{
MessageBoxA(NULL, "Can't find Calculator", "Camvas", MB_OK);
return;
}
GetClientRect(user_window, &user_window_rectangle);
//create
HDC hdcScreen = GetDC(NULL);
HDC hdc = CreateCompatibleDC(hdcScreen);
UINT screenshot_width = user_window_rectangle.right - user_window_rectangle.left;
UINT screenshot_height = user_window_rectangle.bottom - user_window_rectangle.top;
hbmp = CreateCompatibleBitmap(hdcScreen, screenshot_width, screenshot_height);
SelectObject(hdc, hbmp);
//Print to memory hdc
PrintWindow(user_window, hdc, PW_CLIENTONLY);
BITMAPINFOHEADER bmih;
ZeroMemory(&bmih, sizeof(BITMAPINFOHEADER));
bmih.biSize = sizeof(BITMAPINFOHEADER);
bmih.biPlanes = 1;
bmih.biBitCount = 32;
bmih.biWidth = screenshot_width;
bmih.biHeight = 0-screenshot_height;
bmih.biCompression = BI_RGB;
bmih.biSizeImage = 0;
int bytes_per_pixel = bmih.biBitCount / 8;
BYTE *pixels = (BYTE*)malloc(bytes_per_pixel * screenshot_width * screenshot_height);
BITMAPINFO bmi = { 0 };
bmi.bmiHeader = bmih;
int row_count = GetDIBits(hdc, hbmp, 0, screenshot_height, pixels, &bmi, DIB_RGB_COLORS);
D3D11_TEXTURE2D_DESC screenshot_desc = CD3D11_TEXTURE2D_DESC(
DXGI_FORMAT_B8G8R8A8_UNORM, // format
screenshot_width, // width
screenshot_height, // height
1, // arraySize
1, // mipLevels
D3D11_BIND_SHADER_RESOURCE, // bindFlags
D3D11_USAGE_DYNAMIC, // usage
D3D11_CPU_ACCESS_WRITE, // cpuaccessFlags
1, // sampleCount
0, // sampleQuality
0 // miscFlags
);
D3D11_SUBRESOURCE_DATA data;
ZeroMemory(&data, sizeof(D3D11_SUBRESOURCE_DATA));
data.pSysMem = pixels; // texArray; // &bmp.bmBits; //pixel buffer
data.SysMemPitch = bytes_per_pixel * screenshot_width;// line size in byte
data.SysMemSlicePitch = bytes_per_pixel * screenshot_width * screenshot_height;
hr = dev->CreateTexture2D(
&screenshot_desc, //texture format
&data, // pixel buffer use to fill the texture
&screenshot_texture // created texture
);
D3D11_SHADER_RESOURCE_VIEW_DESC srvDesc;
srvDesc.Format = screenshot_desc.Format;
srvDesc.ViewDimension = D3D11_SRV_DIMENSION_TEXTURE2D;
srvDesc.Texture2D.MostDetailedMip = 0;
srvDesc.Texture2D.MostDetailedMip = screenshot_desc.MipLevels;
dev->CreateShaderResourceView(screenshot_texture, NULL, &shader_resource_view);