Thank you! :) If I had started developing Skycraft in 2013, it might have been voxel.js, but it didn't exist at all a year ago. I could have converted to voxel.js, but chose not to, as I have some things voxel.js doesn't yet (lighting, ambient occlusion), and the whole floaty islands thing allows for some special optimizations that would be hard to generalize into voxel.js. So it's just "normal" Three.js., but I really like the voxel.js project!