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Pickman
07-21-2005, 01:45 PM
Hey guys,I'm digging into rigging and corrective blendshapes. My question is how do you add edge loops or cut edges into the original mesh to refine the deformation once it has been bound, before doing any blendshape ? What's the workflow ? Do you just have to turn the skinclusternode off ?
THX

cavetroll
07-23-2005, 11:11 AM
I wouldnīt recommend adding more detail to your model after you skinned it to your sekeleton. you would end up with a large history on your model when adding edges and stuff after binding. this will slow down your scene a lot.
no, you just canīt turn off the envelope of your skinCluster. when you turn ist back on, maya wouldnīt know where to skin the new vertices to.
so, put enough detail in places you will need it.
as for the corrective blendShapes: visit highend3d.com to get some decent scripts for that which handle the different local-point-spaces you have when doing corrBlends.

when you do it directly in maya you would have to duplicate your mesh in the bindPose and add this to your blendShape node. do the tweaks on the duplicate and drive the weight of your corrShape with a joint rotation or sth. make sure your blendShape node gets evaluated BEFORE the skinCluster.
cheers.

Pickman
07-23-2005, 01:04 PM
Hey cavetroll ! Thx for the answer, in fact maya 6.0 has delete non skin history to get rid of modifications on mesh and I have Kiaran cgtoolkit script for building blendshapes in a few minutes...I'm sure there must be a way to modify the base mesh while doing modifications in production pipeline, I'm sure some gurus here have the answer :-)

john_homer
07-24-2005, 10:15 AM
...I'm sure there must be a way to modify the base mesh while doing modifications in production pipeline, I'm sure some gurus here have the answer :-)

Gurus model it correctly, then skin it.
Not skin it then "hack it right".

.j

michaelcomet
07-24-2005, 04:05 PM
Yeah I'd agree, changing topology after is bad.

Typically the workflow is skin, then use something like my free pose space deformer plugin to do the corrective shapes.

Worst case, if point count has to change, export all skin weights, psd targets etc...then kill history, then reapply rigging deformers and reload weights and adjust as needed.



-comet

Pickman
07-24-2005, 07:39 PM
Lol, I was right, you gurus have the answer, even if it is NO, lol, thx for your reply guys, in fact I had nice skinweights but realised I needed an extra row on the shoulder area, that's why I asked this question. It is hard to visualize before the end result, I had never been so far in a rig, modeling, skinning, rigging and PSD or blendshapes script.

Michael I did a rig I'm happy with but it was oriented X pointing down, it was all screwed when I decided to use your psd....I had to reorient the whole rig Y pointing down.
Same goes for modeling, the model deforms nicely except on shoulder area.

Now that I made some mistakes I'll be happy to do it again and learn from both you and my errors.

"Gurus model it correctly, then skin it.
Not skin it then "hack it right"."

I'm really surprised you never go back to model modifications while in production :-)

THX guys for taking the time to answer me.

michaelcomet
07-24-2005, 11:04 PM
Well model changes DO happen in production....it'd be nice if they didn't but sometimes they do. Getting tools to work around it cleanly is a good thing.

As far as Y axis down, my PSD will work with it in whatever axis you want, it just defaults to Y-axis...but you can use it with X or Z or whatever, there is no limitation...

-comet

Pickman
07-25-2005, 09:05 AM
Hey Michael, I experimented weird problems changing the default axis, i realised problems disappeared as soon as i came back to Y default axis. But that was at my first try using your great PSD, really looking forward to getting the money for your cmusclesystem, it really seems tremendous.

THX.

michaelcomet
07-25-2005, 12:42 PM
What weird problems? There's no issues I am aware of....

Octagon
07-26-2005, 10:56 AM
no, you just canīt turn off the envelope of your skinCluster. when you turn ist back on, maya wouldnīt know where to skin the new vertices to.

This is an interesting topic. As far as I know 'Detach Skin (keep history)' did a pretty decent job the last time I used it. Basically it allows you to disable the skinCluster, then fiddle with the geom, add edges etc and then you can reattach it later. Maya doesn't assign any new weights to the new verts but it's still faster to make those points fall in place then to blow away the skinning and reapply weights.
Has anybody tried it? I honestly remember this worked.

twedzel
07-26-2005, 03:35 PM
It'll work but it will leave the history of your modifications in the mesh. Which is messy and in my mind undesirable. You're better off saving out your weights and doing the modifications then reapplying.

michaelcomet
07-26-2005, 08:27 PM
Also at many production studios, Models are referenced in, so this really isn't an option, since model changes are done in a completely separate file from the rig.

Pickman
07-26-2005, 08:51 PM
Do you guys know what the ShapeOrig node is for, what's the point of turning the intermediate object off, it leaves a grey version of your mesh ? Michael, any idea on this node ?

THX

michaelcomet
07-27-2005, 12:24 AM
Orig shapes are the original mesh, that's the real original mesh in the original state, it then feeds through all the history and each deformer affects the points, to finally arrive at the final deformed state, which is shown.

The orig shape will be non deformed, and it's so that there is actually data/points to be there for the deformer and final versions.

Buexe
07-27-2005, 07:44 AM
And if you are really slick you can pump your new geomatry into the Orig node and don`t have to kill your deformer history just because you did some uv tweaking.

Octagon
07-27-2005, 11:34 AM
It'll work but it will leave the history of your modifications in the mesh. Which is messy and in my mind undesirable. You're better off saving out your weights and doing the modifications then reapplying.

I'm quite sure I didn't have any model history on my skin after I did the model changes. Maybe I turned of the history before I did the changes? I think some operations require history but not all of them.

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