View Full Version : Wrap Deformer skinning problems

03 March 2004, 05:37 PM
I am using a low poly model of an arm which has been bound to a skeleton. This low poly arm is deforming a subd arm (just converted the poly arm to Subd) using the wrap deformer. (Besides I am using this technique for the the whole character and I have never encountered any problem except from this one which I can't solve)
When I rotate the bones for the fingers the Subd object breakes and some vertices are moving towrads the coordinate space's origin. The low-poly arm is fine , though.

Playing with wrap deformer options like "weight treshhold" and "max distance" don't change anything. I also checked the deformation order.

Does any1 have a clue?

I've read this question on highend 3d, no answers where given unfortunatly.
I'm having exactly the same problems, so does anybody around here know why this is occuring and how it can be fixed??

:: Galactor ::

03 March 2004, 10:00 PM
I thinck is the same problem I had a while back. I would have to see a pic of where the problem occurs to be shure. Ok, well the way I have fixed my problem is. I had influence objects to help on the deformations and sometimes the influence objects would go throw each other or to a position were it was not practicle. So the wrap would not know what to do and those cv's would return to the origin. So all I did is adjust the animation curve of the sdk's. Or you could move the influence object around and see what hapens.. If you are using a wrap to help on the deformations and sometimes the cv's jump to the origin, is because the wrap is deighn pinched or twisted in a bad way or not a practicle way.

03 March 2004, 10:30 PM
I do have influences included in my rig, butt those are located near the hips of my character. So i don't think they cause the problem that occurs around the hand area.

There are just some vertices that are indeed snapping to the origin. I tried to move or delete the influences, but that only resulted in strange wrapping around the hips, and didn't affect the way the wrap reacts in the hand area.

Right now i deleted the subd geometry, and smoothed the lowres geometry. This works because the highres version was just a conversion from my lowRes geometry.

:: Galacter ::

03 March 2004, 12:45 AM
So you fixed it?

03 March 2004, 01:13 AM
I'm not sure I understand what you were doing but if you are using a wrap deformer on a sub-d surface that is also the low res poly cage for the sub-d surface then you would get double transformations.

So as you have done it is really best to only generate the sub-d surface fromthe poly cage and apply whatever additional deformaers to the cage not the resukting sub-d surface.

03 March 2004, 10:38 AM
I duplicated my lowres Polymodel, then i converted it to subD.
So no i have a lowResPoly and a highResSubd model. These where then wrapped so the lowres was driving the highres model.
So there where double transformations occuring, cause the two models do not have any connection but the wrap deformer.

Did i fixed it?
No, i deleted my subD geometry. Then just before rendering i did a polysmooth action on my lowRes PolyModel. And this looks good enough for this project. But i want it to work with future projects, so if you know the answer, please do give it.

:: Galactor ::

03 March 2004, 11:38 AM
Try this... select the low poly wrap influence object, open up the attribute editor (not channel box, as the attribute we need to change doesnt show up there), and select the transform node of the object (not the shape node, careful :)).
Under Extra attributes, there should be an InflType attribute which is set to 2. Change this value to 1 and you shouldnt have the problems you were having.

What this does is change the wrap method from faces to vertices.

03 March 2004, 04:17 PM
Yes Yes, your the man.
Thanks a lot, strange though that the attribute "Infl Type" is hidden away like that.

:: Galactor ::

03 March 2004, 05:13 AM
No worries :) Yeah, it is really strange that they have it hidden away in the extra attributes of the transform node and not in the wrap node itself. Anyone know why this is?

02 February 2005, 09:07 PM
I had learned this in the gnomon video 2 years ago and promptly forgot about it. I was pulling my hair out.

thanks for the help again! I've seen this post 2 times now. let's see if I can retain this little nugget!

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