What's the best way to draw a fullscreen quad in OpenGL 3.2?

Posted by Phineas on Stack Overflow See other posts from Stack Overflow or by Phineas
Published on 2010-04-06T22:49:08Z Indexed on 2010/04/06 22:53 UTC
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opengl

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I'm doing ray casting in the fragment shader. I can think of a couple ways to draw a fullscreen quad for this purpose. Either draw a quad in clip space with the projection matrix set to the identity matrix, or use the geometry shader to turn a point into a triangle strip. The former uses immediate mode, deprecated in OpenGL 3.2. The latter I use out of novelty, but it still uses immediate mode to draw a point.

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