I recently went away from derivative simplex noise to try out (textured) dudv and normals for water.
I can only say, I have never seen anything so bad in my life. Is it the quality of my texture? It's kinda big.
I had some issues with forming the normal because I couldn't properly combine levels of derivatives. Likely culprit being my math skillz.
The only remaining thing to try is combining levels of sine curves which are not that hard to combine and get derivatives. That will probably look best, but that requires a nasty number of for(;;) in the most complex fragment shader I have. I really don't want that.
Edited by Kaptein, 08 May 2014 - 03:32 PM.