This is from my entry into the best water contest, maybe 15 years ago (a sub on the water). Waves are based on the old plasma.bb, with 2 scalar copies interferring (as far as I see). Also, using vertex color to get some pseudo-volumetric water colorization, as seen in Far Cry back then, adds a lot to it IMHO.
Fredborg won the contest,but refused to take the prize, so it went to Inarie from Germany. Yeah, he won a swiss military knife ^^
Re Optimation: I have added an exporter for the copperlicht.js engine, all trees in one single surface mesh, and all grass in 4 parts (each one less than 32k tris or verts), and the terrain too, and it runs in the browser with a very decent framerate. So I may do the same in Blitz and have it running even faster, while displaying grass all the way to the horizon, too. In the LOD fading, I must see whether fading nearby low poly trees out using vertex-alpha is fast enough, and if not, just fade the highpoly version in and have it covering the low poly one somewhat. However, internal z-sorting of meshes with alpha textures may cause problems, where in the current version the individual tree meshes are rendered in their last positioning order, which z-sorted them during their creation.