Would anyone be able to extend this to provide a version that outputs a gradient vector as well as the noise value? This would very useful for generating surface normals.

Thanks very much for that - given that it's commentary on the simplex algorithm from Perlin it might shed some light on the subject, but I must admit that I'm still not sure I understand the code...

Yeah, I've seen that stuff from Perlin before. The problem is that he's using multiple samples of precomputed patches of noise rather than generating the noise on the GPU.

I'm hoping to generate...

Hi There

I'm using Stefan Gustavson's GLSL simplex noise code (http://webstaff.itn.liu.se/~stegu/simplexnoise/)

But one thing I'm unsure about is that while the implementation returns a noise...

Is redundant shader code removed at link/assembly time? I'm wondering whether I need to worry about splitting up collections of library code so that only used functions are compiled?

I'm a shader...