I'm creating a voxel terrain engine for my game in Unity, but I don't know, what's the best way to implement lighting. I wanted to write it as it is in Minecraft - CPU calculating light for each vertex and then shader multiplying output color by this value, but I've got octrees implemented, which means that one faces are big and other ones are small, which is a major issue when creating per-vertex lighting. I wouldn't like to have to divide bigger faces to get the lighting resolution I want, because then octree rendering optimizations lose their sense. Is there a way to overcome it? Using unity lighting would mean that I have to buy Unity Pro (which is too expensive for me) to make shadows and deffered rendering and I wouldn't be able to tell how dark it is in a certain place on the map. And of course real-time lighting would mean a major performance drop, which I cannot afford. Please help if you can.