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maddav99
01-12-2007, 03:31 AM
Again, this is coming from Maya and not really knowing the ins and out of XSI, what is the alternative to Maya's influence objects for a skinned character in XSI?

bravmm
01-12-2007, 07:49 PM
what do they do??

solarflare
01-12-2007, 08:33 PM
I apologize if I am wrong (I don't have a ton of experience with rigging), but I am pretty sure Maya's influence objects are just a way to use something other than a bone to bind/skin/weight/envelope. In XSI this is just the way it is done...you can bind/skin/weight/envelope to anything. You can create an entire FK chain without a single bone, just by parenting objects and then rigging to them (I believe).

mdee
01-12-2007, 08:57 PM
I apologize if I am wrong (I don't have a ton of experience with rigging), but I am pretty sure Maya's influence objects are just a way to use something other than a bone to bind/skin/weight/envelope. In XSI this is just the way it is done...you can bind/skin/weight/envelope to anything. You can create an entire FK chain without a single bone, just by parenting objects and then rigging to them (I believe).

That's partially true, influence objects can change the shape and deform the geometry according to shape changes, similar to shrink wrap.

There is no direct XSI equivalent of influence objects with "use geometry" checked.

There are a couple of methods which can give similar results
- shrink wrap (I recommed reading help for this one, much better than me explaining) deformer
- you can constrain null to every point of your deformer (influence) object and then bind (envelope) to those nulls. I believe there is a script in netview called AddNullToPoints which does the first part for you.
- do you know that XSI has corrective blendshapes built in? (shape -> deform by orientation, or something similar, can't remeber exactly). Then you can go to secondary shape modeling mode and sculpt on top of your mesh

- of course you can use syflex skin, some custom muscle system, etc..
Hope that helps.

maddav99
01-13-2007, 01:06 AM
I guess I should have claified what Maya's "Iinfluence objects" are and do before posting the question. In Maya an influence object will control deformation of a skinned object to reflect the transforms applied to it. An example would be to make the arm flex when bent as a bulging bicep. You would simply use any type of object, perhaps a NURBs sphere in this case, and have it's scaling transform attached to the bending of the arm. You could then set the weights of the influence object in the general area of the bicep to have it affect the skin to reflect this transform to any amount that you desired with a drop-off to blend with the rest of the mesh. Very handy with muscles are as a soft body in the stomach where you could apply a jiggle effect.

I was aware of the "link with deform" but i wasn't sure of how much control you had over it. I'll look in to the other ideas, syflex and shrink-wrap, to see what they can do and how they work.

Thanks.

maddav99
01-13-2007, 01:08 AM
Syflex is only available in the "Advanced," right?

JDex
01-13-2007, 01:16 AM
Syflex is only available in the "Advanced," right?

That is correct. XSI does have SI cloth in Essentials (and possibly advanced)... it's not Syflex, but it is powerful.

Sil3
01-13-2007, 08:07 AM
That is correct. XSI does have SI cloth in Essentials (and possibly advanced)... it's not Syflex, but it is powerful.

Cloth is also available on Foundations.

maddav99
01-13-2007, 08:18 AM
Let me ask this then, if I use the "link with deform" is there any way to replicate that from one side of the envelope to the other, or copy and paste from one cluster to another? I'm anal and I'd like my mesh to be as symmetrical as possible.

mdee
01-13-2007, 10:41 PM
Let me ask this then, if I use the "link with deform" is there any way to replicate that from one side of the envelope to the other, or copy and paste from one cluster to another? I'm anal and I'd like my mesh to be as symmetrical as possible.

Yes, use GATOR. If you don't have it, there is a way to do it - model in symmetry mode, make sure both joins on both sides have the same orientation (ie you need to correct shape when your joints are rotated to 30 degree, make sure both sides are rotated), then save both shapes (select both corresponding clusters and save deform key, it will save it for both)

If you just need to emulate Maya influence objects in simple form (so your skin/envelope is affected only by SRT, not by actual deform of influence objects) then you can envelope to anything in XSI, use NURBS, implicit geometry, whatever.

P.S. I'd not recommend uisng syflex skin just to do simple corrections of your envelope.

maddav99
01-14-2007, 12:22 AM
Great, I'll check it all out. Thanks.

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