I have created a rocky/grass texture out of two displacement materials it looks pretty good however I know its going to bump up render times.. can you recommend how to make good looking grassy/rock type material from basic materials/not displacement materials? I also want to add trees bushes etc to my whole scene when I add an ecosystem all the trees seem to be roughly the same length and it doesn't look very good and I would like to have more control over where they are placed. I have tried painting them on which is good but still cannot control the scale and if I want to paint a different type of vegetation... I remove some that I don't want to use and it removes them from the whole scene. For instance if I wanted just fir trees and a type of bush in one section. ....and I wanted palm trees in another.

Sorry if I have gone off topic a bit!