UV Mapping

[ChallAcc]

Hi there! I've just built my first model within 3D Coat, and reached tyhe point where I wanted to export it into Substance Painter. However, when I do that, I can't paint on it.

Not sure why, so I looked back in 3D Coat, and noticed that when I switch over to the UV tab, everything disappears. When I switch back over to the other tabs, my model reappears, but for some reason my UV simply isn't.

I'm thinking this may be the issue. In the paint section I can still paint, and I thought a basic UV would automatically be generated... but who knows?

Any help would be appreciated!

[Pangolin Legends: Arceus]

When you try to load the model in substance painter, if you don't have a uv map it will not load your model and will say in the bottom left something like "model not loaded no uv map". I'm not sure (i'm just a demo user at the moment) if 3d coat can generate a uv map for you through a menu option. Like you I would assume it creates a uv map when you paint on it.

Have you tried exporting in all the different formats 3d coat supports? (if more than one, can't remember) Some formats may not support uv maps.

If all else fails you can load the model into Blender and add a uv map there before loading it into substance painter.

[ChallAcc]

Hey, thanks for the reply! I've tried obj, whch doesn't work at all, and fbx, which works but no UV.

Is this a bug then? The model was built entirely within 3D Coat, so it should have a UV. I wish there was a "Generate UV" button.

[pekbro]

3D Coat excels @ UV map creation and editing, youve just got to figure out how it works.
Not super intuitive unfortunately...

[ChallAcc]

Yeah, I've heard that. That's why I'm so surprised that it's skipped the first stage for me. I can paint the object from within 3D Coat, suggesting that it's aware of a UV map, but my object still disappears within the UV tab, and still exports without a map included.

Very annoying! That's why I assume I've encountered a bug.

[pekbro]

Youve just got to remember, most of the time when your working in 3D coat,
your using voxels, not polygons. You must convert to polys before you can
uv map an object... 3D Coat is quite unique in this way...

*if your wondering why that is; its because voxels are
volumetric, until you topologize your object, essentially,
there is no geometry to map...

Its confusing because 3D coat can paint directly on
the voxels and could care less if there is a map or not.
It only creates geometry for other programs to use, not itself...

Youll find out why the first time you do it and wind up with an
object of 5 or 6 million polygons... And it takes 20 mins for your
pc to respond again...


-Cheers

[ChallAcc]

Thanks again! Any idea how to convert from Voxel to Poly? Checked online, and in the program, but not sure if I need to be in a certain tab or not.

I've found the AUTOPO tool, but when I use it, I set the number of polys to something like 500, and it gives me a model with 94 polys. I set it to 100,000 and I have 836. However, I can export my object as it stands, directly to 300,000 polys without an issue beyond it not getting a UV map created for it!

Lovely program, but I'm missing something important to make it useful.

[☠F☺celessMind☠]

the number of polygon you target is not enought to get an efficient topology. so use big value and after that you can delete some edges to reduce the number of polygons

[ChallAcc]

I set it higher, and the program crashes. So far this program is like pulling teeth.

[MAriskaDeville]

@4demon - If your not after a game ready model, you can convert your voxel mesh to a polygon mesh in the sculpt room. Then you can export it out (as dense quads I think) then re-import it into 3DC. When you re-import it 3DC will automatically apply UVs. Export once more and you can then use this model in SP.

Keep in mind Facelessminds advice about polycount vs performance however. This workflow needs a decent bit of horsepower from your PC. It crippled mine when I tested the idea out :(

Also, 3DCs UV room is just for models you import to UV map. For models you build inside 3DC you want to use the UV tools found in the retopo room.

[ChallAcc]

Thanks I'll give it a go! I just wanted to build a model, and then use the auto UV tool on it. I can paint on my object fine, which to me suggests it has a UV already applied in some manner.

Seems like a lot of steps.

[MAriskaDeville]

Originally posted by 4Demon:

I can paint on my object fine, which to me suggests it has a UV already applied in some manner.

Sounds like you have already converted a voxel mesh to a surface mesh - those you can paint on with vertex paint in the paintroom with no need for UVs.

[ChallAcc]

Hmm, not sure I've taken steps to do that. I just want to be able to work on my model in Substance Painter. I'll try out the work around shortly. Happy New Year to you!

[MAriskaDeville]

Oh its easy enough - in the voxtree layer list you will see the letter 'V'. Click on that and it changes to an 'S'. You are now in surface mode and working with tris, not voxels.

Whilst you can switch back to voxels, I recommend you only switch to surface mode for detailing/finsihing.

Anyway stick with it, and happy new year yo you and yours.

[ChallAcc]

Ok, finally given this a go. Exported as dense mesh, but no idea what to import it as. Half the stuff just doens't import anything, and the other half pops up with a message telling me the object is empty. One time, however, it imported a very low poly version of the object.

Hmm... thinking me and this program just don't get along...

[ChallAcc]

Managed to import it back into 3D Coat so I could try the UV, and noticed that it's a very sketchy looking thing. Broken up into 15 different sections. Imported this into substance painter, and it didn't work.

Very strange program. Why is it forcing me to use the low resolution AUTOPO?