Multiple UV Map Question

tyl3r

So lets say I have a Static Mesh, we'll call it WallMesh.
My UVs for the Diffuse Map are set up and utilize overlapping to get the most out of the texture.

I also want an Ambient Occlusion map for the WallMesh, but can't use the same UV's because of the overlapping. So I create a second UV set in Maya, by copying the first UVs to a new set titled map2, and configure them so there is no overlap. I bake out my AO using the map2 UVs.

My question: Is it possible to take this into UDK and set it up so that my main material for the WallMesh utilizes the map1 UVs for the diffuse texture, but ALSO uses the map2 UVs for the AO?

divi

http://www.polycount.com/forum/showthread.php?t=74824

tyl3r

I went through the thread and still can't seem to figure it out. I don't know if I am missing something or what here.

I have a texture that I want to use as the Diffuse on my WallMesh and it uses the UV map 0 in UDK. But in that material I also want to lay an Ambient Occlusion Texture over the Diffuse, but have it affect UV map 2 for the mesh... is that any clearer?

kdm3d

Yeah, you can create your shader to use your diffuse on one channel default is 1, and there is a node to change the channel for the AO to 2. Then, on a basic level, you can use a lerp with your tiling texture going into one part, and a constant set to o for the other lerp channel. Then put your AO map into the blend hookup of the lerp node with the node to change the channel behind the AO map... Does that make sense? I could do a quick mockup if it would help.

Actaully that link up there is exactly what your asking... check out the shader layouts, and combine with what I wrote here...

tyl3r

Ha yah, a quick mockup might be the best, I've been trying it out but can't seem to get it working... it's really starting to frustrate me...

divi

with AO maps you dont necessarily need a lerp since you want the dark parts to be laid over your diffuse and the bright parts to be invisible so multiply works just as well.
in udk the default channel for all texture maps is actually coordinate index 0. 1 is used for the lightmaps, even though that could be changed. But coordinate index 2 and upwards would probably be the channels to put extra maps with different UV layouts into.

the splatter represents the AO map btw.

tyl3r

Thanks for the mockup, I'll give it a try later tonight! Much appreciated!