overlaying GdkPixmaps

[Andreas Sliwka <goff nef wh uni-dortmund de>]

Frickeln - second part.

Hi,
  I want to overlay two GdkPixmaps. The first one is opaque , the second one
  is mostly transparent. How can I accomplish that the I see all the opaque
  pixels of the second GdkPixmap, and on all positions where the second on is
  transparent the pixels of the first one shine through? I tried the following:

---------------- Code Snippet ------------
/* copying from template to buffer */
gdk_gc_set_function(bufferGC,GDK_COPY);
gdk_draw_pixmap(buffer, bufferGC, template,
		posx, posy, 0,  0,  24, 24);
/* overlaying buffer with overlay !DOES NOT WORK! */
gdk_gc_set_function(bufferGC,GDK_OR);
gdk_draw_pixmap(buffer,bufferGC,overlay,0,0,0,0,24,24);
gdk_gc_set_function(bufferGC,GDK_COPY);
/* copying the buffer on the screen */
gdk_draw_pixmap(actual_pixmap,   bufferGC,     buffer,
		0,         0,   posx, posy, 24,  24);
---------------- Snippet End -------------
But that doesnt work.
Can someone help me please?

the whole code (main.c:60-78) can be obtained at
http://trashcan.nef.wh.uni-dortmund.de/~goff/CheeseNMice.tgz

mfg
-- 
Andreas Sliwka   | goff@nef.wh.uni-dortmund.de | ICQ goff:13961062
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