Multiple UVW Maps on same mesh


#1

Hi all ,

Hmm I’m a bit stuck, I always thought this would be something easy but I’m not sure what I’m doing wrong.

So I have a body/face all part of one mesh I want to unwrap. But I want the face to have more detail so I want to unwrap that by itself, and then do the body seperate, while not having to detach the mesh.

I thought this was as simple as assigning it to a different map channel? However, I can’t seem to assign the selected Face faces to a different map channel, everything seems to go across.

What am I missing here?

Thanks


#2

You could use Multi Tile Map or different Mat IDS, in the latter case move/scale unused UVs out of the way.


#3

You need to assign the Map ID’s on the faces themselves. Then assign a Multisub object material to the model. Set the diffuse bitmaps to the corresponding Map channel. Then the UVUnwrap picks that up. Then when you’re in the UV Editor, change the viewable map in the drop down list on the uppoer right to the corresponding map you want to see.

Hope that helps!


#4

Hey thanks for all the responses, it really helps, I didn’t think of the Mat ID part. I’m still getting stuck though when trying to separate them to a different channel. (I haven’t put seams on etc or assigned maps, its just for demonstration proceses of trying to seperate the channels)

So I’ve gotten further in terms of being able to unwrap the 2 different I’ds, but I’m still unsure about how I separate them. Also when rendering the UVW template, how do I hide one channel.

Am I just using the completely wrong technique?

Please see video here, I am determined to understand the technique!

https://youtu.be/-LKQgtRRREA

Thanks


#5

You don’t necessarily need 2 different UV channels.
Might be cleaner that way, but normally you’d only need them if you want to apply 2 different UV sets to the same faces. Also it’s only then that you need to move/scale your unused UVs out of the way, using 1 channel and Mat IDs would destroy UVs already set up that way (unless you move them over exactly one tiling UV square. Sorry about that - brainfart.

Also switching UV channels in the same Unwrap UV modifier means you lose the UVs of the channel you just worked on (unless you copy them over to the next channel, but the old channel will be reset). Unwrap UV works only on the active channel. If you want to have two channels active, you’ll need two Unwrap UV modifiers or collapse the modifier into your base object before you proceed.

For filtering (and I guess rendering) only one Mat ID in the UV Editor you have display options in the lower right corner of the editor window.

And for assigning different maps to different Mat IDs use a Multi Sub Mat like electrotoast wrote.

So basically you would assign your Mat IDs, filter them in the UV Editor to arrange them and a Multi Sub Mat to assign your respective maps. (Or a Multi Tile Map where you need neither Channels nor Mat IDs)


#6

It looks like you’re on the right track. Is there something you’re missing? You have them separated by channel and ID (might be a little redundant, but that’s ok). Looks like all you have to do is make sure your maps and materials are using the corresponding numbers. If you want to see the maps in the UV Editor, just load it from the drop down. You don’t have to separate the geometry. As Noren mentioned, you may need to move each one to a different UV area outside the main 0-1 box so you don’t mess up the other IDs placement. It’s ok as UV space is repeatable.

Unless of course you’re doing this for a game character. In which case you should either split the geometry, or scale down the UV space utilized by the body leaving more room for the head in a single map. If that’s the case, you don’t need separate maps or mats just need to arrange your UV’s accordingly.


#7

Hey guys,

Thanks for your patience, and time to explain, very helpful! I think I have become a little outdated with the process! I was doing the Game method, but this will be for pre-render. I will try moving it outside the main area box, (I have to read up on that a bit)

Really good info, I might hunt down a tutorial, although most of them go into the unwrapping I’ve found not so much the layout.

Happy to hear your process as well!

Thanks