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VanDookie
02-24-2011, 08:34 PM
I'm working on my first character rig for an animation, I have some digital tutors dvds from a few years back that have helped me wrap my head around some of the key concepts but now I'm running into problems in the only area I was comfortable with when I started: Blend Shapes.

http://i25.photobucket.com/albums/c62/nato_vandookie/pess2.jpg

I have at this point a fully rigged and weighted character with a few set driven key controls and some simple curve control objects. But I've been waiting to do the blend shapes. The problem I'm having though is when I apply the blend shape, I get the correct deformation, but my entire character drops a couple inches, this adds on top of each blend shape activated.

http://i25.photobucket.com/albums/c62/nato_vandookie/blends.jpg

Like I said, this is my first attempt at a full character for animation, I have no experience here and am completely baffled. Any help would be appreciated even if that help means I have to start over...

Stavs82
02-24-2011, 10:19 PM
I think the problem is from the order of your inputs on your mesh. The inputs needs to have the skin cluster higher on the list than the blendshapes. If this is the problem then it is easy to fix. Simply select the geo that has the blend shapes on it and then click the button (inputs to selected object). You can find this button to the right of the magnet icon(Make Live) at the top of tool bar. The inputs to selected objects icon looks like a green box with a red arrow. After you click the button then go to All inputs. After that middle mouse drag so that the blend shapes are under the skin cluster. Hope this helps.

I just noticed that you didn't specify a program(or I missed it in the post). My solution was for Maya.

nuternativ
02-25-2011, 02:16 AM
Your character drops a couple inches when activating blendShapes?

I think that because of verticies difference on the base mesh and the target meshes.

Usually, blendShape will store vertex information for every target mesh, and will calculate the difference between the base and target meshes when activated. So, the problem might occours when the base mesh got freezeTransformations so the the object space has been reset and the difference between verticies are on every verticies. That's why the whole thing moves.

An easy work around is to detatch skin on base mesh, duplicate it, set one of the blendShape to -1 so the shape move in opposite diriction- up. Then, snap the duplicated mesh's pivot to any vertex and use the pivot to move the whole mesh to snap the original mesh at the identical vertex point. Freezetransformation on the duplicated mesh and use it as your new base mesh.

hope this helps, excuse my English.

VanDookie
02-25-2011, 03:01 AM
Wow, thanks for your replies!

Stavs82: I am using Maya. I have adjusted the order of the inputs, that was discussed in one of the digital tutors tutorials, that was an issue that used to plague my blend shapes and was my immediate reaction to the problem. Thanks!

nuternativ: I'm not going to pretend I understand everything you mentioned, and that was not due to your english... but, I did detach my skin and when I did, the skin rose about an inch... So I readjusted the skin, refroze transformations, and rebound... problem solved! Thanks so much!

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02-25-2011, 03:01 AM
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