I'm working with XNA on a 3D Game, and I'm trying to have a proper and nice environnement. I actually followed a tutorial to create a terrain from a heightmap. To texture it, I just apply a grass texture on it and tile it a number of times.

But what I want to do is to have a really realistic texturing, but also generate it automatically (for example if I want to use Perlin noise to generate a terrain and then texture it).

I already learned about multi-texturing, loading a map file with different colors for different textures, but I don't think this is really efficient, for instance for cliffs or very steep areas it will tile a texture badly as it's a view from the top. (Also, I don't know how I'll draw roads or dirt paths with that.)

I'm looking for an efficient solution to realistically texture mapping procedurally-generated terrain.