GLSL: How to get pixel x,y,z world position?

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Published on 2011-02-04T15:13:50Z Indexed on 2011/02/04 15:25 UTC
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opengl

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glsl

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fragment-shader

I want to adjust the colors depending on which xyz position they are in the world.

I tried this in my fragment shader:

vec4 pos = vec4(gl_FragCoord); // get pixel position

but it seems that the z-coord is always towards my camera... how do i make the coords independent from my camera position/angle?

Edit: if it matters, heres my vertex shader:

gl_Position = ftransform();

Edit2: changed title, so i want world coords, not screen coords!

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