This is something Dave's asked for, I finally got enough math together in my head to implement it. A texCUBElod that doesn't have sharp edges. What it basically is, is a drop-in function to be called in place of texCUBElod. In turn, it calls texCUBElod in a couple places, and blends the samples smoothly. The edge in the top picture's reflection is, of course, what I am referring to. Well, to be honest, this is cheating slightly - I didn't yet implement the corner case, so the corners of the map are still visible if there are sharp transitions. But once I've added that, I'll post it up. EDIT: There, it's completed. See lower post for download link, since pasting the code didn't work. Stick this into renderer\common\utils.cg, probably, since that's included in most shaders already. Then just replace texCUBElod() with texCUBElod_soft() in the fragment (_f.cg) shader. Code: #include "../common/utils.cg" (just stick this with the other #includes if it's missing) Since normal texCUBE() doesn't go to mipmaps within view there's no point implementing it for that one.