i want to put 3 things on the sreen
,a map information(ie. an image), over that my drawing and again one more drawing on it. the objects has to transparent, so that i can see the map information.
in directx triple buffering is possible, how about in opengl?
please help me…
I don’t know if triple-buffering is possible in opengl, but I don’t think you need it for this problem.
You seem to want to draw things on top of each other using transparency to see through the top layers. This can be done using alpha blending.
triple buffering is not what you want. does this information change? drawings of what, ie txture mapped stuff or polygonal or…
You don´t need triple-buffering for this.
And it is not supported in OpenGL.
triple buffering is supported under extensions I thought. sure you could use a pbuffer anyways
I think it is an extension. Anyways for your problem, you need the accumulation buffer. You would render the map onto it first, then the second drawing on to that and the third drawing on to that. You would have to alpha blend the second and third drawings to the map. This is only if you store all three drawins in seperate buffers. Or else you could just normally draw the map to the background and follow it up with the two other drawings alpha blended (this is without accumulation buffer).