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Gabba123XXL
09-13-2011, 03:20 AM
Hello,
I have just a question about fog generation. It is completely depricated. How I do it? With shaders? When yes, can somebody give me a reference example or even a link?
Or there are other techniques to do it?

Alfonse Reinheart
09-13-2011, 03:27 AM
The kind of fog computed by the fixed-function pipeline is just a cross-fade, based on depth (or some other positional value), between the color produced by lighting and the fog color. The OpenGL specification explains the math behind the various fog computations.

Gabba123XXL
09-13-2011, 04:34 AM
So, I have to compute the color of each vertex in the shader?

Alfonse Reinheart
09-13-2011, 01:02 PM
Where you do it is up to you. Personally, I would use per-fragment fog, but if you want to exactly emulate the fixed-function fog, you compute the fog interpolation parameter in the vertex shader and do the cross-fade in the fragment shader.

Gabba123XXL
09-13-2011, 01:13 PM
Ok!
Thanks a lot!

Gabba123XXL
09-13-2011, 01:17 PM
But here I have the next question...
glTexCoord*(..) is depricated as all the other fixed functions like glVertex*(..).
How I have to handle the texture coordinates? Like the vertex coordinates and binded in vertexarray/buffer object?