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Rendering a bitmap image of Windows screen shots as a DirectX texture

I am developing a DirectX application for "3d desktop", which should display the current contents of the desktop window (for example, "Calculator") as a 2D texture on a rectangular surface in directx (11). I am very close, but very afraid using the screenshot BMP → Texture2D step. I have a screenshot-> HBITMAP and DDSFile-> rendering texture works successfully, but I can’t take a screenshot-> rendered texture.

So far I have been working on the “capture window as screenshot” bit:

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);

At this point, I have a bitmap of the window referenced by HBITMAP hbmp.

My code also works for rendering a DDS file as a texture on a directx / 3d rectangle:

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);

:

Texture2D ObjTexture
SamplerState ObjSamplerState
float4 PShader(float4 pos : SV_POSITION, float4 color : COLOR, float2 tex : TEXCOORD) : SV_TARGET\
{
    return ObjTexture.Sample( ObjSamplerState, tex );
}

( - ):

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);

: LoadFromDDSFile - , HBITMAP screencapture ObjTexture?

HBITMAP hbmp shader screenshot_texture, ( , - "data.pSysmem = & bmp.bmBits", , ):

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
    );

::::::::: ::::::::::::::

& bmp.bmBits , - "malloc" . Chuck Walbourn , , , ( 32 /). - /, - , , .

:

  • FindWindow,
  • CreateCompatibleBitmap SelectObject PrintWindow, HBITMAP
  • malloc, ( *)
  • GetDIBits, ( *) HBITMAP
  • CreateTexture2D
  • CreateShaderResourceView,

, Windows direct3d:

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);
+4
2

& bmp.bmBits , - "malloc" . Chuck Walbourn , , , ( 32 /). - /, - , , .

:

  • FindWindow,
  • CreateCompatibleBitmap SelectObject PrintWindow, HBITMAP
  • malloc ( *)
  • GetDIBits ( *) HBITMAP
  • CreateTexture2D
  • CreateShaderResourceView

, Windows direct3d:

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);
+1

, BITMAP 32- RGBA. , , bmPlanes 1 bmBitsPixel 32, , 4 . BMP .

BMP BGRA, DXGI_FORMAT_B8G8R8A8_UNORM bmBitsPixel, 32.

-, bmWidthBytes, bmWidth.

data.pSysMem = &bmp.bmBits; //pixel buffer
data.SysMemPitch = bmp.bmWidthBytes;// line size in byte
data.SysMemSlicePitch = bmp.bmWidthBytes * bmp.bmHeight;// total buffer size in byte

bmBitsPixel 24, DXGI . 32- , DXGI_FORMAT_B8G8R8X8_UNORM.

bmBitsPixel - 15 16, DXGI_FORMAT_B5G5R5A1_UNORM Direct3D 11.1, , 16- DXGI . .

bmBitsPixel 1, 2, 4 8 , DXGI.

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