Texture Painting Question

[Dave Buckley]

I'm getting my head round texture painting at the minute, and have a question regarding splitting an unwrapped uv layout across multiple materials.

 

I may never encounter this situation - not in arch viz anyway, but would love to know the best route to take. So it's a hypothetical answer I'm looking for.

 

How would I assign multiple shaders to one UV layout.

 

For example, part of the UVW layout represents metal, other parts might represent wood.

 

I essentially end up with two materials in my mat editor and only one diffuse map.

 

Am i right in thinking I'd need to use that one diffuse map in both materials, but combined with a mask to determine which parts are associated with each material?

 

Hopefully that makes sense.

[Dave Buckley]

just to elaborate further, I can solve the above with a blend material and mask to separate the two shaders to the correct parts of map.

 

but what if there are more than 2?

[RobNJ73]

It's been a while since I had to do this, but if memory serves, it was multiple UVW maps, each one assigned a different map channel combined with a multi-subobject material with each material's assigned to a corresponding map channel (that is, material #1's maps were all Channel 1, material #2's maps were all channel 2, etc.. )

 

Not sure if my memory is faiilng me on this, but I think this is the right direction, even if not the exact solution to what you were asking.

[TSuess]

Multi/SubObject. Select a SubObject of an editable mesh or poly and in that objects rollout under Surface Properties use SET ID. It will correspond with the ID in the material itslef.

[TSuess]

You can also do a blend of a blend of a blend. Use the Slate Material Editor it's much easier to navigate these types of materials.

[-MerlyN-]

Thats what Material ID's and the Map Channel's are for. If I need just on UV layout with different materials just assign different material IDs in edit poly mode and use a Multi/Sub Material.

 

A couple of years ago I also managed to assign more than one UV layout to one object by working with several UV Unwrap mods set to different Map Channels. I just tried it again quickly and it didnt work, but I am not quite sure why. I know its possible however. Would be easier to just split the object though I think.

 

However if you want to have two materials on the same face you'll have to work with a blend material and a mask.

[Dave Buckley]

cheers Merlyn, thats what I thought. All tutorials I have seen all seem to create the finished photoshop file in one material. But what if that uv layout contains parts with different anistropy values for example.

 

But yeh. It is going to be a case of blends or MSO's and masks. I did kind of do it yesterday. I created 3 different materials, in diffuse, spec and bump slots of each material I placed 'mask maps', i then used the same diffuse map in each map slot of each diffuse channels' mask map, and the same for spec etc, i then controlled which parts were which by creating masks in PS from the original diffuse .psd.

 

It all gets a little confusing and you are right I could just break it up, and have two different layouts for different parts, but you hit the nail on the head, if the two materials cover the same face, let's say paper peeling off to reveal brushed metal. I'd unwrap as one complete object, build the texture in PS, but would then need two materials in Max. That could be done with blend and just a mask in the mask slot. It only gets overcomplicated with the MSO as described above when more than 3 materials need splitting over 1 uv layout and the parts can't easily be split, for example, the peeling away paper will span the same faces as the metal.

 

And cheers for the help to the other guys too. Like I say i should rarely come across this but just wanted to know the answer

[-MerlyN-]

Yeah. Nice example, btw. This morning I couldnt really think of any situation where you'd need this, but you hit it.

 

And yes, thats what bugs me of most tutorials. They only explain the simple things. I've never encountered any tutorial that would explain the really complicated situations where thinking out of the box would be required.

 

For the peeling away paper I'd go with a blend material. That would probably be the easiest way of dealing with it. Not sure as I have never used a blend map with more than a base and one coat layer, but pretty much anyway.

 

Glad if I could help.