How to make plants grow over time

[bira3D]

There's an "Animated EcoSystem Populations" example at e-on's site:

http://www.e-onsoftware.com/products/vu ... am/?page=5

where plants grow in a terrain over time. I suppose it was made in the function editor with an animated gray scale color map over time. I'm trying to figure it out how but had no success till now. It would be very nice to have a tutorial or a hint on how they did it.
Thank you!

[vovka]

good request i will record this