So starting off,

1/ I'm going to be generating a terrain from L3DT and transfer it into 3DGS.
2/ Convert .dds models of rocks and trees to .mdl. As posted elsewhere, transparencies are a problem in MED.
3/ Write a function to return surface at x, y in the terrain.
4/ Write a function to return a requested number of points for trees. I'll randomise x, y values and return x, y, z, values, where z (height/ground) would be the surface of the terrain.

This function will require a few parameters.

num_trees, number of trees
Radius of each tree (Rmin, Rmax) - each tree will be in its own square box. 2 parameters will be need so that the size of each box will be randomised between a min radius to max radius value. This will make the trees less uniformed when viewed from above.

I think a density function should return the number of trees for an area and also the higher the density, the smaller the diff between Rmin and Rmax.

Hopefully the terrain will be automatically vegetated with a few trees and not look too uniform from afar.

Globals such as FOREST_DENSITY, JUNGLE_DENSITY, DESERT_DENSITY can be pre-determined.

There probably are a few current projects that automatically vegetate terrain, but I thought this will be a good learning project for myself and gets me straight into contact with handling models. Always loved 3D graphics.