Yep, vertex shading is being used for the mesh. Since I wanted each triangle to be a flat shaded solid color, vertex shading make it pretty simple, with the option to still overlay a texture if I so choose.

I really am just using a height map derived from a noise function. Most of the interesting code is how noise values are blended to give interesting terrain, and making Unity play nice with true multithreaded generation in order to run at a decent speed while spitting out chunks of terrain.

I'm probably not gonna do much more work with this project. I'm currently playing with Compute Shaders and seeing if I can implement Marching Cubes to give something more interesting/varied than a heightmap.