When generating the last levels of the terrain LOD, i'm placing some trees randomly over the patch surface. The trees are made of two crossed quads with a texture on it. For each vertex of the current terrain patch, i determine the density of trees based on the altitude and slope of this vertex. The tree is then randomly displaced (to avoid seeing organized rows/columns of trees) and randomly rotated around the vertical axis.
There are three problems with that:
1. Individually, each tree is fugly - in the future i plan to procedurally generate real 3D trees with LOD, and impostors at high distances.
2. Because i haven't optimized the code, it's awfully slow.
3. The placement of the trees is not perfectly matching the textures on the ground, since the textures parameters (altitude/slope) are modified with noise values, but the trees on the CPU aren't.
I'm not going to spend more time on that now, as i just wanted to make a quick test to get an idea of the potential problems.
I'm now going to start on the integration of the terrain engine, the textures prototype, and the planets/atmosphere from space.