I hope I post it in the right forum.
I've played with procedural generation of Perlin Noise in fragment shaders using RenderMonkey to develop those shaders. The problem is that when using a big integer array in fragment shader (512 int entries) framerate is very low (single digit). I've changed array to texture and now some strange lines appeared. Additionally my shader causes RenderMonkey to fail when using nVidia card.
First version (using int array):
Further versions (using textures):
Anyone have a clue what could be wrong? My shader is based on: http://http.developer.nvidia.com/GPUGems2/gpugems2_chapter26.html and Ken Perlin examples.