View Full Version : Seam problem with Vertex normals

12 December 2009, 03:09 PM
Dear members,

I am trying to make a character for a real-time game engine that is able to have limbs switched out with code. To do this, we modeled it to have seams in places that will have minimal movement once bound, like the bicep. At the seam, the geometry stops and terminates with interior faces, and the rest of the limb is a seperate piece of geometry. Our goal is to make it seamless, but in real-time it is very noticable, especially the neck seam.
We think it may be because the vertex normals at the border edge loops have different values. What would be the best and/or quickest way to hide the seams?
(Working with Maya 2009)

thank you very much in advance!


12 December 2009, 06:42 PM
Have you attempted selecting the seems and softening the edges? (polygon shelf>normals>soften edge)

Or just use the move normals tool and tweek the offending edge untill it blends better.

My apologies if i've misread your post!

12 December 2009, 11:38 PM
Dear MrJuzah,

yes I tried to softening the edges,but no luck!Also I tried to match the vertex normals with the rotation(edit) tool but the seam is stil noticeable.

I was reading in a post the following:

"One of the biggest issues 3D artists encounter when using normal maps is the appearance of seams wherever the UV's for a particular vertex are split (wherever your uv boundaries are).

This issue can be fixed by simply creating an additional edge in your geometry that has the same tangency as its neighboring edge (also known as an inline edge). By doing this you will now have an edge where you can "legally" split your uv's without affecting the tangency. This gets rid of any normal or bump map seams. Alternatively you could generate your normals procedurally, in which case the broken tangency is taken into consideration."

I do not know if that would fix the problems,since all UV mapping and generation of gaming maps allready made.Also all paint weights and animations are ready.:hmm:
Thought to ask the community if was any shortcut and I do not have to throw into garbidge so much work!:wip:

Dear MrJuzah,thank you anyway for your answer!

12 December 2009, 06:13 PM
Ah!! Well there ya go eh! I learnt something in the process of trying to help you :P

Best of luck with the modellign!

12 December 2009, 08:02 PM
Since your problem stems from a Geometry Seam as opposed to an UV Seam, the method you quoted wouldn't work...

But by removing the capping polygon at the swappable limbs, or excluding them from Gouraud Shading (if that is possible in your engine), you should be able to at least minimize the visibility of the effect...combine that with inline edges and you could theoretically get rid of it altogether...(you might have to make sure that the inline edges of both parts and the edges of the seam are aligning)

12 December 2009, 01:26 AM
Dear Piflik,
thank you for your feedback.I will test it and I will post a reply.Hope it will work as you are saying!:thumbsup:

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12 December 2009, 01:26 AM
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