headus 3D tools

michaelws · Posts: 10 Joined: 18 Jul 2007

I love the program. Here is a little anomaly. Doesn't seem to affect the unwrapping, but was wondering what it might imply.

After I load in the obj and select "Find" in Symmetry and click on the edge and hit the spacebar, I get some yellow polygons...you can see them on the wrist area in the attachment.

Again just wondering what this implied in my mesh. Thanks

Is it because one of the polys has more than 4 vertices? Just noticed that.

headus · Posted: Mon Jul 23, 2007 5:11 pm Post subject:

Yellow polys means there's a difference in the topology between the left and right sides at that point. You should compare those polys with the same ones at that point on the other wrist, possibly marked with yellow polys too. If you can remodel your mesh so its perfectly symmetrical (i.e. no yellow polys) you'll be able to use the symmetry copy S hotkey later on when you're flattening.

If you cant see any difference, email me that mesh and I'll have a look myself. It might be a bug in UVLayout, not your mesh.

Phil

r_knightly · Posts: 74 Joined: 29 Jun 2007

also check your export options, some formats might triangulate ngons and wont do it the same way on each side. something to keep in mind, tho it dosnt look like the case here

michaelws · Posts: 10 Joined: 18 Jul 2007

Thanks...I sent the mesh as it should be and looks symmetrical. I don't alter the obj export options. It is set for quads and polys and whatever else (I can't remember now without looking..but the same export settings I use for getting the meshes into Zbrush 3.

thanks for the suggestions.

headus · Posted: Mon Jul 23, 2007 6:29 pm Post subject:

r_knightly is right! There has been a difference in triangulation of
that 5 sided poly on the left and right sides. I don't think UVLayout is doing
that, because even before the recent update, it could handle up to 7 sided polys
before triangulating them.

michaelws · Posts: 10 Joined: 18 Jul 2007

thanks for the quick analysis...I will play around with the export settings. I know I should just add another edge along both sides of the wrists.

Thanks again.

andyburm · Posts: 4 Joined: 31 Jul 2007

.obj will tend to triangulate everything that is not a quad poly in your 3D app (even if set to quad in the export options). So if you have a 5-sided poly on your mesh it will most likely be a triangle afterwards.

headus · Posted: Fri Aug 03, 2007 8:33 pm Post subject:

The OBJ format itself can support any number of sides; its the application in this case (whatever that is) that would be doing the triangulation. Remembering back I think the 3DS format only supported quads, so if this is 3DS Max it could be related to that; maybe the obj export goes via 3DS somehow?

Phil

andyburm · Posts: 4 Joined: 31 Jul 2007

you got a point Phil...although I encountered this in max and maya before

michaelws · Posts: 10 Joined: 18 Jul 2007

What can one do to correct this? I notice that the triangulation is not mirrored in the sample shown and the polys I created in max 9 were symmetrical ( used the symmetry modifier).

Relayer · Posts: 16 Joined: 12 Mar 2007 Location: Christchurch NZ

Triangulate it manually so it's symmetrical, is what I'd do. It's only a couple of polies. It'd be pretty easy. You could also redo that area so it's only made up of quads. That's more work though. Wink

r_knightly · Posts: 74 Joined: 29 Jun 2007

michaelws · Posts: 10 Joined: 18 Jul 2007

Thanks all..and r.knightly, I will check out your max script...many thanks. Going to Colorado Monday to see the folks for a week or so...back on the 15th.

By the way, even with this little tri-glitch..the uv unwrap works like a charm in max...love this program...it almost makes unwrapping fun. Can't believe my luck in stumbling across an article about it.

Thanks again to all.