Please see the UV Smoothing Section (you may have to scroll down)
I have noticed that a lot of people are using what appears to be Linear UV smoothing.
Some practical examples of linear UV mapping on characters can be seen;
- The Mari Example Scene (https://www.foundry.com/products/mari/tutorials) - Oats Studio Rakka Model available on Steam (http://store.steampowered.com/app/652150/Oats_Studios__Volume_1_Assets/) - Article on Accurate Displacement maps (http://www.cggallery.com/tutorials/displacement/) Select V-Ray for 3ds max and see how you have to break the uvs to force them to be linear ?
I am hunting down and researching this topic of UV style and if its entirely necessary to have linear UVs. In any case I would think it a good idea for Unfold to have a 'style' that can be applied to the UV set
Welcome back to the Unfold3D forum. I am happy to see you there. Did you tried Unfold3D Virtual Space beta ? I want to thank you because 30% of the new features come from your requests. We could do all you requested, because you asked a lot, but we did our best.
About UV smoothing, the topic is interesting. UV smoothing take place at render time when the renderer compute UV derivatives of the subdivided mesh. Adding smooth makes the UV derivatives smoother and the result can be visible for shader that use them. Honestly, and from my knowledge, there not a lot shaders that use them, most shaders don't use UV derivatives. But at the moment you have anisotropic materials, speculars and more generally reflectance properties will look better when UV are smoothed properly. Note that in that case, dedicated UV sets are used to specify the anisotropic direction. Regular UVs (not used for anisotropic field) should be set to linear.
About Unfold3D, we could offer the option to set UV smoothing property style on UVs. The problem is that I think that there is no standard way to specify that property among mesh files (OBJ or FBX).
That subject need to be dug a bit more, but I think it is more in the 3D software that the unwrapper that this option should be set.