graphics
fractals
Back in 1995, I put together a fractal landscape generator. It included support
for a snow-line, the boundaries of which were determined both by altitude and
steepness of the mountain section. The shader was a simple polygon engine with
phong coefficients, z-buffer and back-face removal.

Your basic fractal mountain.

Low resolution mountain, to show how snow is applied.

High resolution mountain with snow.

Very high resolution mountain. About a million polygons
used to create this image.