How to add drawing to existing picture?
I have got an image with some background. I would like to add there couple drawings, like circle or square but without erasing that background. That mean i can't use glutSwapBuffer() function which i used to use and actually i don't know how can i render my new drawing. Any ideas? 
How to add drawing to existing picture?
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I have got an image with some background. I would like to add there couple drawings, like circle or square but without erasing that background. That mean i can't use glutSwapBuffer() function which i used to use and actually i don't know how can i render my new drawing. Any ideas? 