Is it possible to create a terrain object from a sphere?
I'm building a "Little Prince" type planet that the game camera rotates around and would love to use the super optimized terrain to build up the exaggerated mountains.
Is there a way to use a quad mesh object as a stand-in for terrain that the terrain tools will work on?
I can build my own mesh, but it will likely be a lot heavier than a terrain object.
This new Q&A site ROCKS, BTW.
Terrains are only height maps on planes... there's no spherical support that I'm aware of. Depending on your needs, you may be able to fake something by putting multiple terrain objects together, but you're probably just going to have to model your terrain in a 3D program.
answered Nov 18 '09 at 12:50 AM
You can't use unity's terrain engine at all to make spherical terrains, even by putting multiple terrain pieces together. Much of the optimisation done within the terrain engine relies on the terrain being a flat horizontal plane which is deformed upwards only by the heightmap. Same with the trees & grass system, etc - all designed to work on terrain which lies on the X-Z plane. For this reason, the rotation controls in the inspector of the Terrain GameObject have no effect at all.
The most common way of achieving spherical terrain that I've seen is to build your own "CubeSphere" using 6 heightmaps, one for each side of the cube. I've done this before, and I've seen at least two other people on the IRC channel accomplish it.
The technique is essentialy this: