(let me know if this needs to be moved - dg)

xfrog (or “greenworks organic software”): http://www.xfrogdownloads.com/

one of my lsystem attempts - a very stylistic approach (all right angles). trees are built out of cube primitives for an artificial life simulation, in isometric projection:

the cubes approach was too slow (for my old graphics card in 2004) so I moved to using camera facing geometry (sprites), textured with faked normals to make them shade according to the lighting to appear cylindrical. with a bit of texturing it looked like this:

this might be a technique for background mass foliage - level of detail maybe…