How to draw into device context - winapi

Question

I have a bitmap image in form of array of 32-bit integers (ARGB pixels: uint32 *mypixels) and int width and int height. I need to output them to a printer.
I have the printer context: HDC hdcPrinter;
As I learned, I need first to create a compatible context:
HDC hdcMem = CreateCompatibleDC(hdcPrinter);
Then I need to create an HBITMAP object, select it into the compatible context, and render:
HBITMAP hBitmap = ...?
SelectObject(hdcMem, hBitmap);
BitBlt(printerContext, 0, 0, width, height, hdcMem, 0, 0, SRCCOPY);
And finally clean up:
DeleteObject(hBitmap);
DeleteDC(hdcMem);
My question is how do I create an HBITMAP object and put mypixels into it?
I found two options:
HBITMAP hBitmap = CreateCompatibleBitmap(hdcPrinter, width, height);
Looks good, but how do mypixels get into this bitmap?
HBITMAP hBitmap = CreateDIBSection(hdcPrinter /*or hdcMem?*/, ...);
Will it work? Is it better than option 1.?

Answer 1

This function creates a bitmap and sets it to an initial image.
Irt's a bit fiddly to access the bits directly, but it can be done.
HBITMAP MakeBitmap(unsigned char *rgba, int width, int height, VOID **buff)
{
VOID *pvBits; // pointer to DIB section
HBITMAP answer;
BITMAPINFO bmi;
HDC hdc;
int x, y;
int red, green, blue, alpha;
// setup bitmap info
bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
bmi.bmiHeader.biWidth = width;
bmi.bmiHeader.biHeight = height;
bmi.bmiHeader.biPlanes = 1;
bmi.bmiHeader.biBitCount = 32; // four 8-bit components
bmi.bmiHeader.biCompression = BI_RGB;
bmi.bmiHeader.biSizeImage = width * height * 4;
hdc = CreateCompatibleDC(GetDC(0));
answer = CreateDIBSection(hdc, &bmi, DIB_RGB_COLORS, &pvBits, NULL, 0x0);
for (y = 0; y < height; y++)
{
for (x = 0; x < width; x++)
{
red = rgba[(y*width + x) * 4];
green = rgba[(y*width + x) * 4 + 1];
blue = rgba[(y*width + x) * 4 + 2];
alpha = rgba[(y*width + x) * 4 + 3];
red = (red * alpha) >> 8;
green = (green * alpha) >> 8;
blue = (blue * alpha) >> 8;
((UINT32 *)pvBits)[(height - y - 1) * width + x] = (alpha << 24) | (red << 16) | (green << 8) | blue;
}
}
DeleteDC(hdc);
*buff = pvBits;
return answer;
}