I’ve created a cliff face model which I’d very much like to place grass on. From what I can make out however Unity only allows you to place this on it’s own terrain?
I’ve thought about creating a dummy terrain underneath my cliff asset but it would be quite time consuming and I’m unsure how effective it would be.
So before I go ahead and attempt that I thought I’d post here to see if there is some way to do it differently?
Any advice greatly appreciated.
P.s. Sorry if this sounds a dumb question but I’m still trying to get to grips with Unity!
Correct, the terrain system has a method of storing grass and trees that wouldn’t work on arbitrary objects.
–Eric
Thanks for the reply Eric.
Damn, that’s annoying!! 
This should work with most 3d Packages. Maya, Max, etc: Go with the ramp method. Drop a linear ramp material (black/white) onto your cliffs (ramp material should be oriented like a projection from the side but not from the top) and then render your cliff from orthogonal top view. Use the created image as heightmap inside Unity.
http://www.halflife2.net/forums/archive/index.php/t-16207.html
http://unity3d.com/support/documentation/Components/terrain-Height.html