How can I get ID2D1Bitmap from a BITMAP in Win32/Direct2D? HDC hScreenDC = GetDC(nullptr); HDC hMemoryDC = CreateCompatibleDC(hScreenDC); state.sw = GetDeviceCaps(hScreenDC, HORZRES); state.sh = GetDeviceCaps(hScreenDC, VERTRES); HBITMAP hBitmap = CreateCompatibleBitmap(hScreenDC, state.sw, state.sh); HBITMAP hOldBitmap = static_cast<HBITMAP>(SelectObject(hMemoryDC, hBitmap)); BitBlt(hMemoryDC, 0, 0, state.sw, state.sh, hScreenDC, 0, 0, SRCCOPY); hBitmap = static_cast<HBITMAP>(SelectObject(hMemoryDC, hOldBitmap)); DeleteDC(hMemoryDC); DeleteDC(hScreenDC); BITMAP bmp; GetObject(hBitmap, sizeof(BITMAP), reinterpret_cast<void*>(&bmp)); ID2D1Bitmap* d2dBitmap = bmp; // Somehow do this I have trouble finding the tutorial for this. So I ended up here. Regards, @thebluetropics

GetDIBits + ID2D1RenderTarget::CreateBitmap from lpvBits

Hello @thebluetropics , You can load a Bitmap based on decoder's implementation . For an example, see How to Load a Bitmap from a File , How to Load a Bitmap from a Resource (Direct2D) . In order to load a Bitmap, you can try GUID_ContainerFormatBmp .

Win32: BITMAP to ID2D1Bitmap

Accepted answer

Castorix31 83,206 Reputation points

2022-09-30T06:54:12.03+00:00

GetDIBits + ID2D1RenderTarget::CreateBitmap from lpvBits
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1 person found this answer helpful.
thebluetropics 1,046 Reputation points

2022-09-30T09:15:19.003+00:00

@Castorix31

What is HDC should be? Somehow, I got confused about this. There is two variable that maybe match this (see my code above): hScreenDC, hMemoryDC
But what if there is somehow only BITMAP are available and nothing such HDC?

Castorix31 83,206 Reputation points

2022-09-30T09:41:48.093+00:00

The DC where the hBitmap is selected (in your case, hMemoryDC)

thebluetropics 1,046 Reputation points

2022-09-30T12:02:14.613+00:00

Is there any other way, like get the HDC from only a BITMAP?

The hMemoryDC, as you can see, it was deleted by DeleteDC()

Castorix31 83,206 Reputation points

2022-09-30T12:10:12.617+00:00

You must call GetDIBits before DeleteDC (I tested with your code and I get a correct ID2D1Bitmap, containing a copy of the screen DC)

thebluetropics 1,046 Reputation points

2022-09-30T12:48:23.85+00:00

How do you do GetDIBits()? If possible, can you show me the tested code?
I have no idea with the remaining parameters, start and total of scanlines, etc

Castorix31 83,206 Reputation points

2022-09-30T13:14:20.443+00:00

The quick test I did from your code =>

HDC hScreenDC = GetDC(nullptr); HDC hMemoryDC = CreateCompatibleDC(hScreenDC); int nCX = GetDeviceCaps(hScreenDC, HORZRES); int nCY = GetDeviceCaps(hScreenDC, VERTRES); HBITMAP hBitmap = CreateCompatibleBitmap(hScreenDC, nCX, nCY); HBITMAP hOldBitmap = static_cast<HBITMAP>(SelectObject(hMemoryDC, hBitmap)); BitBlt(hMemoryDC, 0, 0, nCX, nCY, hScreenDC, 0, 0, SRCCOPY); BITMAP bmp; GetObject(hBitmap, sizeof(BITMAP), reinterpret_cast<void*>(&bmp)); int nWidth = bmp.bmWidth; int nHeight = bmp.bmHeight; BITMAPINFO bmi = { {sizeof(BITMAPINFOHEADER), nWidth, -nHeight, 1, 32, BI_RGB} }; DWORD* pBits = new DWORD[nWidth * nHeight]; if (GetDIBits(hMemoryDC, hBitmap, 0, nHeight, pBits, &bmi, DIB_RGB_COLORS)) { unsigned int nDPI = GetDpiForSystem(); D2D1_SIZE_U sizeu = D2D1::SizeU(nWidth, nHeight); D2D1_BITMAP_PROPERTIES props = D2D1::BitmapProperties( D2D1::PixelFormat( DXGI_FORMAT_B8G8R8A8_UNORM, D2D1_ALPHA_MODE_IGNORE ), nDPI, nDPI ); ID2D1Bitmap* d2dBitmap = NULL; // m_pD2DDeviceContext3 is ID2D1DeviceContext3* hr = m_pD2DDeviceContext3->CreateBitmap(sizeu, pBits, 4 * nWidth, &props, &d2dBitmap); // d2dBitmap is OK here (tested with m_pD2DDeviceContext3->DrawBitmap) } SelectObject(hMemoryDC, hOldBitmap); DeleteObject(hBitmap); DeleteDC(hMemoryDC); DeleteDC(hScreenDC);

thebluetropics 1,046 Reputation points

2022-09-30T22:56:45.457+00:00

@Castorix31

Thank you for the example. May I know why do you put SelectObject(hMemoryDC, hOldBitmap) at the end?

Castorix31 83,206 Reputation points

2022-09-30T23:33:47.38+00:00

Because a GDI object (here hBitmap) must not be deleted while it is still selected into a DC.

thebluetropics 1,046 Reputation points

2022-09-30T23:38:14.817+00:00

@Castorix31

I have tried using DrawBitmap() but the entire client area is black?

Full code

Castorix31 83,206 Reputation points

2022-10-01T00:19:51.847+00:00

Your CreateBitmap is wrong : not created from pBits...

thebluetropics 1,046 Reputation points

2022-10-01T00:24:53.217+00:00

It works as expected, thank you for helping me, @Castorix31
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Win32: BITMAP to ID2D1Bitmap

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