Terrain Workbench
Prototype a procedural heightfield before you build it in World Machine. Drag the sliders and watch the terrain, its slope and its drainage follow. Roll a ball down it, make it rain, then bake it to a grid and erode it into river valleys.
Made with instacalc The calculator that shows your work.
Remix "Terrain Workbench" into your own editable copy. Tweak it, share it, make it yours.