Really nice work! Runs ok on my old laptop (2.2 GHz, 3 GB RAM, GeForce 8600M GT). When adding hills and caves it gets somewhat laggy.
Perhaps you can even implement Minecraft's lighting style? I don't know how to do that, though. According to Notch "it adds no performance penalty per frame, and a small one every time a tile changes". Perhaps it's a bit tricky.
Its not tricky. Its very easy. You just have to change the lightning if something in the level changes. Since the sun shines only in -z direction you can just update the "pillar" were a block was added/removed. And you just have to update the upper 2 blocks, because all blocks underneath those two are and will stay dark. EDIT: And i think minecraft only changes the ambient value. Since this is the easiest way of doing that.
