If a 3D shape (e.g. in Maya/Blender) is edited (e.g. extrude), the underlying UV often should be edited as well.

The UV editing is useful - to make a triangle occupy enough texture pixel, and make texturing artist work easier.

However, it is a tedious and very repetitive process.   

Fortunately, Maya can automatically update UV and the underlying texture.

(^ reference : https://knowledge.autodesk.com/support/maya/learn-explore/caas/CloudHelp/cloudhelp/2018/ENU/Maya-Modeling/files/GUID-6AB281B4-1653-4CC5-B4D4-A87516261F2E-htm.html  )

But, what if the texture is created by Photoshop? 

I don't think Maya will automatically hack into my ".psd" file.  Thus, my original Photoshop file will be deprecated/obsoleted.

Question: 

• What is your workflow when editing a shape? 
• As an artist, do you feel tedious that UV and/or underlying image have to be edited as well? 
• How do you solve it?

I am new to 3D modeling.

10 hours ago, hyyou said:

• What is your workflow when editing a shape? 
• As an artist, do you feel tedious that UV and/or underlying image have to be edited as well? 
• How do you solve it?

I'm not really an artist (I just dabble) so hopefully you will get some better answers:

1. Make sure the shape / uvmap is final before texturing
2. Yes
3. I don't  

PTex has some potential to solve issues like this. Some texturing systems may potentially make it easier to make edits (perhaps substance painter approach of procedurals with masks, versus traditional texturing, you'd have to ask substance users).

I know true artists have a greater tendency to faff and can never commit to a final version. Aside from moving round / warping uv islands, you could also look into using as many texture maps as you want and then baking down to a final texture map with a 2nd set of UVs. That won't work with photoshop layers either though.

Well the solution is to never put yourself in scenarios where you're going to edit UVs after your textures are created. I normally will create my meshes, do the UVs, and make a density check prior to baking and texturing. Texturing is only done at the final stage. I had only one scenario in which I did alter my UVs after a texture job, but this was a project in which I had procedural materials made and smart mats done, so I just reapplied them. If I was doing manual brush strokes then I would have to redo those which would take some time. (Adding new UVs to an existing map thankfully is easy, the problem is changing what you've already textured and making it look proper)

If you're doing your texturing through Photoshop and want to make UV edits, then you'll need to load in those UVs once changed to Photoshop as a layer, then match up your prior texture to conform to the new UV. You're going to lose by doing this as your textures are raster so scaling and warping can reduce the quality, it is just a mater of how much.

I cannot answer on how Maya does their warping, but if it just needs a format like PNG or something, then save your PSD as such as try it. I know in Substance we have an option to load in a new version of the mesh and "preserve texture strokes", but normally it doesn't work well unless your object is super simple.

Just don't put yourself in this scenario to begin with. Plan better.

Thank a lot, lawnjelly and Rutin.

Ptex is interesting!  Thank for the Disney link.  I just notice there is Ptex tool in Maya.

On 5/12/2019 at 7:37 PM, lawnjelly said:

... I know true artists have a greater tendency to faff and can never commit to a final version. ...

It is exactly what I am afraid of.

On 5/12/2019 at 8:09 PM, Rutin said:

Just don't put yourself in this scenario to begin with. Plan better. 

That is too hard for me.  I am a programmer - I love to refactor things too often.  

I will try to use procedural texture more.

     Definitely, texturing is a final step. And Rutin's suggestion of testing pixel density is important. It's quick to check, and can help to minimize the amount of times you have to adjust UVs (and you may have to adjust more than once to get a UV layout that makes sense.) 

     As for my workflow, I love to see models without texture. Having a strong, interesting silhouette can do wonders. I will model as many details as I can before considering to UV. There's a fancy mode in Maya that generates a quick AO preview in realtime, I like to model with it on sometimes to help give a sense of depth as I pull out shapes.

     I used to hate UVing. It is something that needs to be done with every model that I create. But, it's not so bad once you get used to it. Think of it as a challenge to yourself, to see how you can improve how you packed these UVs compared to the last model you tried. It's almost like art itself, trying to pack all these little UV islands together to maximize texture usage  But certainly, you will be UVing every new asset you model.

     At work, we primarily use Substance Painter or Designer to create textures. They are easily updatable, layering works well enough, and if you do need to change UVs, Painter (for the most part) will recognize and update your texture to match. We do have Photoshop, but honestly, I really only use it to edit an already existing texture, and that's only if someone lost the Painter/Designer source files in the first place.

     Now, if you are absolutely stuck with Photoshop, and you must change UVs after doing a considerable amount of work, Maya has an option to bake a textured object using old UVs onto an updated object with new UVs. This works best as long as the geometry doesn't change, but it is a destructive process. You'll get a new texture for use in Photoshop with the new UVs, but will likely not be able to use any of your old layers if the new UVs are drastically different from the old ones.

On 5/29/2019 at 3:36 PM, NeoBrea said:

we primarily use Substance Painter

Thank, NeoBrea.  I just watched some VDO ; Substance Paint is so cool.  Now, I has more options, yea. 

Look like drawing texture in Photoshop is wrong to begin with, but every approach has its own downfall.

I just need to select the least painful way.  ?