[PyOpenGL-Users] First fragment shader - corrected

[Mads I. <mp...@co...>]

Please ignore the first post which had errors. This one is correct

OK, so its time to write the first most simple fragment shader ever. But
it doesn't work:

void main()
{
        gl_FragColor = vec4(0.5, 0.5, 0.5, 1.0);
}

No teapot - just black. Changing to

gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);

gives red teapot, and vec4(0.0, 1.0, 0.0, 1.0) and vec4(0.0, 0.0, 1.0, 
1.0) gives green and blue teapot. But any RGB triplet with values < 1.0 
are always truncated to 0.0. For example:


vec4(1.0, 0.5, 0.0, 1.0) -> pure red
vec4(0.0, 0.5, 0.5, 1.0) -> pure black

I have no clue about whats up.

Best regards,

Mads

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| Mads Ipsen, Scientific developer                            |
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