I wrote an open source object placement utility that allows for placing objects on a terrain using the mouse.
It consists of a terrain and a water surface (pond). The user can select from 3 different models of trees and place them on the terrain.
Here is a demo:
I hope people will find it useful for object placement in scenes or using it as a base for terrain editors and such.
The code is not perfect so any comments and suggestions are welcome.
Souce code: https://github.com/lkarydas/ogre_object_placement_utility