GDI + only outputs monochrome to DC memory

Question

I am trying to double-buffer in an MFC application and am trying to use DC memory with GDI +. However, although I called CreateCompatibleDC (), I only get a monochrome image. Here is the code:

CDC bufferDC;
CBitmap bufferBitmap;
bufferDC.CreateCompatibleDC(&dc);
bufferBitmap.CreateCompatibleBitmap(&bufferDC, 300, 300);
bufferDC.SelectObject(bufferBitmap);
Graphics g(bufferDC);
g.Clear(Color::Green);
dc.BitBlt(0, 0, 300, 300, &bufferDC, 0, 0, SRCCOPY);

Instead of a green patch, I see a rectangle with fading black and white dots. I even tried saving the bitmap to disk after calling g.Clear (). This is really a 1-bit depth file.

Any ideas what went wrong? Thank.

Answer 1

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Answer 2

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&dc CreateCopmpatibleBitmap.

Answer 3

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