This is really awesome, considering my current (first ever) graphics engine which just uses standard polygon rasterization can't even render a few rotating cube

This is really awesome, considering my current (first ever) graphics engine which just uses standard polygon rasterization can't even render a few rotating cubes without starting to break a sweat. And you've got billions of everything! You say the grass is green-space. Do you mean that you just generate the grass as a texture and blit it to a framebuffer or something equivalent? (i.e.: it's never "real" geometry on the GPU). Do you generate your visuals by rendering a fullscreen quad and having shaders do all the work is there actual polygon work involved? Just curious, nice work! EDIT: drat, it seems I missed a few comments, you already answered most of my questions. So feel free to disregard them. I'm leaving the comment to show that I really like the things you've done with the engine, it looks fantastic (and $deity knows how much fun it can be to work on something like that)