UV overlapping with normal map in Maya

aeryis

I have overlapped uvs for a jacket in Maya. The sleeves are sharing the same uv space and are not flipped. The normal map looks fine in the high quality rendering viewport, but when I render it out in mental ray, the right side is correct while the left jacket sleeve is inverted. I've been trying to figure out how to override this. If I duplicate the sleeve and mirror it by changing scale X to -1 and then freeze transformations, the normals will invert and I'd have to reverse them back, and in turn, inverting the normal mapping, same thing if I were to plainly mirror it, or if I were to combine it with the rest of the jacket parts. The only ways I've figured to get this to work is to keep the faces flipped or sacrifice UV space by having 2 sleeves in 2 separate spaces. This is in terms of not being used in a game engine...

Anybody that has any input with this will be greatly appreciated. Thanks a bunch!

Bal

Yeah it's tricky to find out how to fix this, found a solution to this a few years back, by checking random settings in the MentalRay options with a friend at work.
You have to check the the "Maya Derivatives" checkbox in your MentalRay render settings, under the Options tab, Performance section.

(Edit: I misread, what I describes alows you to render out normal maps on flipped UV shells without mental ray flipping the normal direction, might alow you to solve your problem anyways?)

aeryis

Bal wrote: »

Yeah it's tricky to find out how to fix this, found a solution to this a few years back, by checking random settings in the MentalRay options with a friend at work.
You have to check the the "Maya Derivatives" checkbox in your MentalRay render settings, under the Options tab, Performance section.

(Edit: I misread, what I describes alows you to render out normal maps on flipped UV shells without mental ray flipping the normal direction, might alow you to solve your problem anyways?)

Yes! Checking the box on Maya Derivatives did help. Thanks so much!