[solved] Mesh Problem / Using Maya Exporter

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rukos1
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[solved] Mesh Problem / Using Maya Exporter

Post by rukos1 »

Hi!

searched in the forum, but can`t find a solution for my problem.

i have Maya File with 2 boots
Image
After the export they look like this in lexiview:
Image
The light from the left side is lithting up the inner side of the left boot
Image
Image

i have reversed the normals, deleting the history and modify the tangents without success. Using the cleanup command caused an error in lexiview when i tried to load the mesh.

the maya 8 file, the mesh and material file can be found here

now i don`t know what to do else to solve this.
best regards rukos1
Last edited by rukos1 on Thu Aug 23, 2007 8:26 pm, edited 1 time in total.
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Anathema
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Post by Anathema »

With the risk of appearing like a total dofus, what exactly is the problem? At first glance everything looks just fine. The only thing that differs is the light in lexiview vs Maya's default light.
Would you care to ellaborate what I am missing?

Oh it seems the inside of the shoe is missing near the back? It's hard to tell from the camera angles you've posted.
It seems you've verified those speciffic normals. Have you checked if double-sided is on in object poperties, and the backface culling?
If it is on try turning off double-sided and see what happens.

Is the pivot at 0,0,0, does anything have negative scale?

Sorry I have no experience exporting from Maya to Ogre, so I can't deliver definite answers or help. I'm a XSI user so can't check your file from home.
mklann
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Post by mklann »

To clarify the first posting a bit, there are two problems:

1) although the normals in Maya appear to be correct, the surfaces in ogre appear as if the normals were flipped. That's to say the surfaces are visible from the inside and not from the outside. There is a light to the left of the left shoe and as you can see the inner side of the right boot is lit. On the last screenshot you can see that the outer surface from the left boot (which is turned the wrong way) is lit.

2) if we flip the normals of the left boot the surfaces are displayed correctly. But the inner (right) surface of the left boot is lit and not the outer as it should be.

We didn't create these models ourselves but we assume that the left boot was somehow copied from the right one. We checked doing a mirroring but the resulting boot was displayed fine in ogre.

So I guess we need to understand better the normals and possibly tangents work in ogre and it would be really great to know a way to diagnose this problem somehow.

Many thanks!
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Anathema
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Post by Anathema »

Try this scene and see if the results are exactly the same. Pretend they are good looking boots yeah hehe. They are UV mapped, no negative scale, double sided and normals set to face. Note how the numbers on texture are inverted on the inside of the shoes. On the outside they will look correct from any viewing angle. This is a good way to test.

Image
Last edited by Anathema on Fri Aug 24, 2007 12:32 am, edited 1 time in total.
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Anathema
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Post by Anathema »

The .mesh and .material files are exported using ogreExporterForMaya defaults. I've included the scene file so you can do your own exports according to your needs and testrequirements. Hope it's of some help at least .
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mklann
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Post by mklann »

Thanks, Anathema!

see below
Last edited by mklann on Thu Aug 23, 2007 8:28 pm, edited 1 time in total.
rukos1
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Post by rukos1 »

Thx Anathema,

can`t open the maya file because just have maya 8.0 and the file is an 8.5.

The Problem is solved now!

The geometry of the left boot was negative scaled and this was the reason for the inside/outside problem of the faces. To solve this Problem, i normalized the scale values with the "Freeze Transformations" function in maya from the modify menu.

best regards rukos1
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Anathema
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Post by Anathema »

I'm glad. It's good practice to never have negative scale on models, other than temporary of course. It is very handy for modeling. Just not so good for exports.

I wish you tons of development fun now.
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