landscape blending textures

Unity Engine
1

I have a perlin generated landscape with uv coords.
Since the terrain is big, I have a grass seamless texture repeated many times.
I’d like to have some areas with sand, how can I blend a sand texture in it?

Thanks

2

Some of the terrain shaders on Unify wiki could help: LayerShader or TerrainTwoLayerBumped

3

Yes, it can work, but I need a solution working on all video cards. I was thinking to create blended textures to map transition areas. Is it the only way to go?

Thanks

4

That could work, but then you lose the ability to tile the texture (unless you want to tile the sand parts as well). The LayerShader can be modified to lay down the textures in several passes (it would still need a dual-texture video card, but that’s basically all cards you can find today).

5

Is it possible to specify a ARGB color for each vertex?
This way I could build a mesh for each texture and make some vertex invisible or partially invisible.
I need to specify vertex color also to “give depth” to the scene.

Thanks.

6

You can import vertex colors from modelling tools that support it and you can assign them from the scripting interface too:
http://unity3d.com/Documentation/ScriptReference/Mesh.html

7

Thanks!
I was reading only code snippsets where only vertices,uv and triangles are assigned.
I’m going to try a multi material landscape.