I also remember some terrain-generating demo (for Vista Pro, maybe?) that I had for the Amiga that let you render a scene of a landscape after setting some height variables, water size for lakes, tree type and density, and possibly even snow level on the peaks (hard to remember for sure after 25 yers...). You could watch the scene gradually build up from the lowest point to the top of the final peak.
Of course, the render times were very slow. I'd set the parameters around lunch and, maybe by dinner, I'd have a nice little digital Bob Ross scene.