View Full Version : having an issue with polygons, possibly normals

01 January 2009, 06:14 AM
so im having issues with polys in xsi pictured below: (

the funny thing is where the poly is cutout, on the opposite side the poly is filled in. i know i've come across this before in the forums but i really have no clue what to search for to find the answer.

your help is appreciated


01 January 2009, 09:25 AM
Try the following: select the polygons in question, go to Modify>Poly.Mesh>Invert Polygons,
or if selecting them is too hard: select all of the others, invert them, select all and then invert them all again...
or get the "xsi_usernormalediting_v2_2"-Plugin from te old Netview (or download it here ( )

01 January 2009, 09:40 AM
hm, the thing about that is i tried it earlier, while it seemed to fix the problem the polygon normals are all facing the same direction. not only that but when i reversed the normal that face turned black and it appeared as though there were border edges around the face

is there a way to set all the normals to one way

like "set to face" command in maya



01 January 2009, 04:40 AM
so i tried some stuff and figured i should post to see if maybe some more information might help someone help me.

i did a search earlier in the forums and found a post about imported maya user normals. when i check my polymesh it doesn't have anything listed under the "clusters" attr underneath the polymesh "node"

when i take a look at the mesh, the characters right side displays perfectly, that is, the way i want it to. the left side however displays as pictured above. when i tried duplicating the right side and scaling -1 it had the desired effect, but as soon as i performed a polygons > merge op on it the normals switched to what is pictured above. symmetrize polygons does the same thing.

i've been taking a look at other meshes constructed in xsi and none of them seem to have this problem. when i made a plane and snapped the four points to the face giving me the problem the plane displayed the way i wanted it to, however when i performed a symmetrize polygons op to that plane, the mirrored side behaved the same way the mesh is now. so i can't imagine it's because of the fact that i imported the head model as an obj. but i can't for the life of me figure out whats going on or how to fix this issue. its almost if the normals are reversed but when i look at them they are fine.

can anyone offer any insight?


01 January 2009, 07:08 PM
If the head looks fine in Maya, you can export it in .obj format and when you import it into XSI check the " import normals as user normals" option. Then the normals should look like they did in Maya.

01 January 2009, 01:47 AM
Is your mesh clean? Double faces? Multiple vertices?

01 January 2009, 04:00 AM
which polygon or polygons are you refering to? It's not clear by your post or picture what is wrong with it....if you're refering to the "dent" in the left side of his head (screen right) it just looks like a non-planar polygon, but I'd have to see the mesh to be able to tell for sure...

give a little more info on what exactly the problem is and it will be easier to diagnose....

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01 January 2009, 04:00 AM
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