-I've found a rather easy way to improve the "side of map" effect, where the water looked weird near the sides of the map. This re-uses the code to build "sides", basically. This is a big improvement on some maps.
-I've found a way to fix redness. Haven't really been able to see any red pixels (except for the "moving-the-camera" related bug, but that's a different thing). This fixes in particular Extinct Volcano (@elexis ).
-Slight improvement to reflection near the edge of stuff, by shifting the clipping plane down a tad (same thing done with refractions).
-Code improvements make entities under water (such as fish) look better.
Side of the map: