How do you actually texture a high poly model?

LiviuD3D

Hi everyone. The short version of my question is: "How does one go about texturing a high poly mesh properly?". Google only returns results related to backing details on to a low poly, but almost nothing about what I am trying to achieve. I want to obtain a properly textured high poly model instead of a game ready low poly mesh similar to the example below:

I figured that the intuitive thing to do would be to first unwrap the low poly version, create the textures and then subdivide, but when doing this the texture gets distorted around the seams. 

As a workaround to this, I am currently subdividing the low poly mesh with 1 iteration (TurboSmooth - using 3Ds max), unwrapping the result and then subdividing again with my textures applied. 

This minimizes the distortion around the seams considerably to the point where it's barely noticeable since the geometry doesn't get stretched that much after subdividing a second time, however the downside is that the unwrap workflow becomes a real pain in some cases both for me and the computer since I am unwrapping a poly heavy mesh. I'm not sure this is the proper workflow.

I honestly ran out of ideas for figuring this out and for things to google and I would be VERY grateful if someone would enlighten me. I suspect that the way I am doing things is wrong since it is such a hassle. Does anybody have any suggestions?

Thanks in advance

Dihemi

LiviuD3D said:

(TurboSmooth - using 3Ds max)

Use OpenSubdiv. OpenSubdiv gives you options on how the UVs are subdivided.

Smooth (Always sharp) behaves like a normal turbosmooth. Edge only and/or corner smooths everything except the UV borders and/or corners. Bilinear doesn't smooth at all (only use this one if your mesh has equal spread out topology, like all polygons are the same size). Experiment with those settings a bit.. Most of the pitfalls of regular subdividing still apply though (dangers of distortion, using extra edge guards, rounding corners. How you UV your mesh is still important).

As to texturing high poly objects; texturing your mesh at intended subdivision (or near intended) should also help.

That's mostly it. As far as I know. I'm likewise interested to hear whether there's some improved tech or workflow as of recently.

LiviuD3D

Thank you so much for the advice. I had a hunch that OpenSubdiv might help, but I'm not used to it at all. I will definitely experiment. Thank you

kanga

Ah I dont think subdividing the mesh affects the uvs. Your first post gives the clue. Are you automatically unwrapping? You should be using the unwrap modifier. Place your seams on the lowest sub D, apply the seams, unwrap, open the uv editor. Select an island, dunno what its called as these days Im on Blender, find relax in one of the menus and hit it. Rinse and repeat.

The max unwrapper has straighten functions, so you can straighten the boarder, freeze it and relax the internal uvs. With uvs you should just look for that on yt and there should be loads of info.

oglu

Subdividing does effect uvs. Depending on your subD settings (Boundary rules). If you dont have enough support loops your texture will get stretched.
The easiest way to check if you model is save to toggle subD on and off and look if your edges move.


I postet this some years ago. Its for mudbox but its the same in all tools using opneSubD.

Ghogiel

https://www.youtube.com/watch?v=eG7xQvtIoAU

sprunghunt

For a hipoly you don't even need UVs. You can often just use a box projection 

it's done using the place3dtexture node in maya 
https://knowledge.autodesk.com/support/maya/learn-explore/caas/CloudHelp/cloudhelp/2018/ENU/Maya-LightingShading/files/GUID-1CC2519F-4800-41C2-8348-3751A6F41EA3-htm.html

to get noise along the edges you can use combinations of curvature and ambient occlusion with noise shaders. This is just like doing it in substance designer but inside the shader in your renderer. Here's the curvature node in arnold:
https://docs.arnoldrenderer.com/display/A5NodeRef/curvature