Question

I have some legacy MFC apps, and I’d like to use the Cairo drawing engine to add some charts and graphs.

I’m searching for a small example of how to get that to work. Basically, once I’ve created a PNG or GIF file, how do I get that show up in an MFC CView window?

My google-fu is not finding any good clues.

Answer 1

From my demo samples,

// cairo_surface_t *surface;
// cairo_t *cr;

// surface = call_win32_surface_create_with_dib_T(CAIRO_FORMAT_ARGB32, 240, 80);
// cr = call_create_T (surface);

// call_surface_write_to_png_T (surface, "hello.png");


HDC src = call_win32_surface_get_dc_T(surface); // <--------
BitBlt(dest, 0, 0, 240, 80, src, 0,0, SRCCOPY); // <--------

Assuming that you already have a surface you can use something like the above sample.
dest is the HDC handle to the window you want to render the cairo surface.

Update: CView::OnDraw()

You should implement the OnDraw() method for your CView (inherited?) class.

You can use the pDC pointer to draw the cairo surface, ie:

pDC->BitBlt(0, 0, 240, 80, src, 0,0, SRCCOPY); // "HDC src" is mentioned above