I think ten years ago I had this problem when I was generating terrain types for a voxel world simulator (today everything with blocks is called 'Minecraft'), a

I think ten years ago I had this problem when I was generating terrain types for a voxel world simulator (today everything with blocks is called 'Minecraft'), and I was trying very hard to explain my problem to a statistician at my university. I never got a good answer, and it would be interesting to try to go back and solve this in a better way. One of the hardest problems is generating smooth edges between terrain types, as they can be both hard and too wide at points.