Mirroring UV map and normal map creation question

lkraan

I know this must have been mentioned here before but I couldn't find it...

I was wondering what I have to keep in mind when I want to mirror the mapping of a model that a normal map will be created for.
In the model that I am working on I want both arms to use the same mapping, texture and normal map. To do that I have to offset the mapping of the "clone" with a value of 1 so that both mappings aren't on top of each other.

But I would also like to mirror the mapping of the face, chest armour and belly/groin area right down the middle. Can I use the same technique for this?
Will this mirroring cause a seam?

Eric Chadwick

We were just talking about this over in P&P, Rorshach and others had some good info.
http://boards.polycount.net/showflat.php?Cat=0&Number=91531&an=0&page=0

Rick Stirling

It depends on your engine and coders, but generally a mirror will cause a seam, and a very nasty one at that. Sometimes you simply wont notice, and at other times it is glaringly bad.

lkraan

Thanks guys!
I'm working on a mp model for either D3 or Q4. From looking at the existing textures in the game's pk4 files they use mirroring so I'll just go ahead and do that too to same texture space.

kat

You need to take a look at the material files for D3 and Q4 as there's a 'special' parameter in there which they use on character models called "unSmoothedTangents" (although it can be used on other models).

I've got two working character models done for Doom 3 without too many noticable artifacts from mirroring the UVWmap.