cancel
Showing results for 
Search instead for 
Did you mean: 

Archives Discussions

Wibowit
Journeyman III

Problems (visual artifacts) with Perlin Noise

Strange lines when using texture instead of integer array

Hi,

 

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):

http://www.ii.uj.edu.pl/~tarsa/Material.zip

 

Further versions (using textures):

http://www.ii.uj.edu.pl/~tarsa/Material2.zip

http://www.ii.uj.edu.pl/~tarsa/Material3.zip

 

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.

0 Likes
1 Reply
frali
Staff

I don't know how RenderMonkey is now since it has reached end of life and AMD no longer supports RenderMonkey.

If you write your own opengl program, you will get the warning message like "Large size of this xxx shader may cause slow execution". It means that the big array causes the scratch buffer using, the poor performance may be expected. We strong recommend you to using other ways like uniform array,  texture buffer and so on.

If you still have problems when running your program NOT using RenderMonkey, please tell me.

Sorry for the inconvenience.

0 Likes