Best tools inside of Maya to use when creating character LOD's and maintaining UV's

3qaureman

I've been messing around lately with LOD's and my main problem at the moment is being able to maintain normal map information on the lower LODs shared UV's.

I've noticed that when optimising using the target weld option effects how the normal map look on the LOD, for example sometimes it creates artefacts, where as, deleting edges tends to give better results.

Unfortunately the results I get still aren't ideal and I could really do with some tips on the subject as I can't find very much information on Character LODS online.

So what are in your opinions the best ways to deform/optomise a mesh whilst maintaining silhouette and the UV's for use with the higher LOD's normal maps. (would appreciate Maya examples)

throttlekitty

It's a very esoteric thing, you're always going to have some amount of artifacts with any heavy normal map use. The most generic rule is to remove the smallest/least significant details, polys that don't contribute to the silhouette, and lastly anything that comes close to being flat compared to neighbors to hit whatever your budget is.

Transfer Attributes UVs can be hit or miss, and it's fantastic when it does hit.

3qaureman

my only worry with that is that with bigger models I could be spending more than an hour optimising it, and since transfer attributes looks as thought it can be only done at the end, it's not something I'd want to be gambling with.

Ideally I'd want more control over the optimisation, being able to careful optimise my model while seeing how each change is effecting the normals.

I'm curious, are there any fundamentals of optimising your models for LODS? for example. "ONLY delete edges, don't weld" (no idea if actually a fundamental)

I'm having a really hard time researching this part, I can't seem to find a strong set of rules anywhere and every time I try to create an LOD I get unusble anomalies in my work.

Melazee

I think that the lower LODs will always have deformed map information, not much you can do about it unless you have a unique map for the lower LODs (but a lot lower resolution). But I basically avoid using target weld as much as I am able. If I want to move verts together, I find that often the normal map will deform less if I turn on "preserve UVs" and manually snap it to the required verts. Then I will merge them. 

If Maya freaks out about not being able to preserve UVs at any point, then I tend to just cut in new edges, manually deleting the others. It takes longer than simply welding, but you can preserve your nice normal map a bit better. Weld UVs does mess it up sadly.  

On my phone right now so no examples in Maya unfortunately! I will get some screenshot examples for you tomorrow:)