Merge two meshes + transfer weights - Adapting Softimage workflow in Maya

[Nicolas Esposito]

Hi all,

I already asked this question on a Maya forum and I didn't get an answer basically...

I'm merging together two rigs, one for the head and one for the body.

What I'm doing is parenting the root of the head rig to the neck bone of the body, then merge the two meshes and transfer the weights ( using the merge PPG ), in order to keep the enveloping on both of them ( and later on a bit of smoothing on the weights ).

This is my simple workflow in Softimage, the main reason is to have a single mesh with both head+body rigged.

Now I'm translating the same workflow in Maya.

Parenting of the head rig to the body rig not a problem, done.

The problem is when I'm trying to merge and create a unique mesh with both envelopes...looks like the weights can't be transfered or some scripting is needed in order to do that....

Well, nothing out of the box allow me to do that in Maya?

If I'm not wrong the merging operator act as GATOR, and I know that the tool is not available inside Maya, but seriously there's no way to merge and blend the weights between two meshes?

Sorry to bother you with quesion regarding Maya but looks like here some of you use both of them so better ask :)

Cheers

Nicolas

[Jordi Bares]

Unless this changed recently this can't be done out if the box in Maya, please correct me is I am wrong.

In Houdini you can use attribute transfer.

Jb

Sent from my iPhone

[Martin Yara]

I haven't used that much Mayas latest versions, but AFAIK no.

You would need to:

- Reset to Bind Pose

- Duplicate obj A and obj B

- Combine duplicated unskinned obj A to obj B (getting obj C)

- Select obj C and apply bind Skin.

- Select obj A, obj B and obj C and apply Copy Skin Weights (inside Animation / Skin, Edit Smooth Skin)

- Delete old obj A and obj B

Martin

[Nicolas Esposito]

Good to know, it just requires more clicking...

Thanks Martin

I'm so tempted to use Houdini :) 

[Graham Bell]

Yeah, you can do much of the stuff from GATOR inside Maya, but some things are scattered about.
The great thing about GATOR is that it's all in one place, kinda a 'one stop shop'

G

From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Nicolas Esposito
Sent: 25 March 2014 08:58
To: soft...@listproc.autodesk.com
Subject: Re: Merge two meshes + transfer weights - Adapting Softimage workflow in Maya

Good to know, it just requires more clicking...
Thanks Martin

I'm so tempted to use Houdini :)

2014-03-25 9:47 GMT+01:00 Martin Yara <furi...@gmail.com<mailto:furi...@gmail.com>>:

I haven't used that much Mayas latest versions, but AFAIK no.

You would need to:

- Reset to Bind Pose
- Duplicate obj A and obj B
- Combine duplicated unskinned obj A to obj B (getting obj C)
- Select obj C and apply bind Skin.
- Select obj A, obj B and obj C and apply Copy Skin Weights (inside Animation / Skin, Edit Smooth Skin)
- Delete old obj A and obj B


Martin

[Jordi Bares]

That is good to know… thanks

Jordi Bares
jordi...@gmail.com

> <winmail.dat>

[Emilio Hernandez]

Will this method work as well with the blendshape node?

-------------------------------------------------------
Emilio Hernández   VFX & 3D animation.

[Nicolas Esposito]

Excellent question, I would like to know it too

[Siew Yi Liang]

Hi Nicolas:

In this case, unless the meshes need to be unibody for some reason (uv maps etc.) I would keep them seperate in Maya, it is easier to seperate weights this way, back them up and restore them seperately should the need arise.

While the Copy Skin Weights tool in Maya works, I use will use the AESkinWeights script, it's far more reliable imho and doesn't rely on UVs like the old tools do.

If the meshes need to be combined, Martin's method will work fine, although I would add that as far as possible try to only select the joints that are actually IN the skinCluster before saving out the weights, will save you a ton of headaches with empty weights and painting them later :P (do a cmds.skinCluster('skinClusterName', q=True, inf=True) to query the deformers associated with a skinCluster)

@Emilio: OOTB no. However you have absymmesh right? :) You can use that to actually restore details from a different topology mesh altogether, even if the vertex order has changed (which it will in this instance). So it will be annoying, but what you can do is for every shape in the old mesh you had, duplicate your new base geo by that amount, and then take the old blendshapes and use absymmesh to essentially 'project' their details down to those new target shapes. It's what I used to do when sculpting corrective blendshapes in ZBrush actually and going back and forth between Maya.

Yep, obviously not as elegant as the shape manager hehe. But hey, if you're ever stuck in this situation....at least you can now save the day! :P

Hope that helps!

Yours sincerely,
Siew Yi Liang

[Emilio Hernandez]

Thanks for jumping in Siew.

I found a quick and fast solution for this last one.

Send to Softimage button.

-------------------------------------------------------
Emilio Hernández   VFX & 3D animation.

[Szabolcs Matefy]

Haha. With Softimage merge, and Gator I can implement a new character into our game in a matter of minutes…

 

From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Emilio Hernandez
Sent: Tuesday, March 25, 2014 5:08 PM
To: soft...@listproc.autodesk.com
Subject: Re: Merge two meshes + transfer weights - Adapting Softimage workflow in Maya

 

Thanks for jumping in Siew.

Send to Softimage button.

[Nicolas Esposito]

Oh, c'mon, thats cheating :-P

Anyway thanks Siew

[Siew Yi Liang]

@Emilio: Oh, does that actually work?! I've never trusted any of the "Send To" workflows since they're all version-dependent and I'm running different versions of Maya/XSI, but if it works for sending shapes back and forth, I might have to see if it helps out in my workflow too... :D

Yours sincerely,
Siew Yi Liang

[Martin Yara]

Yes, pretty much everything requires a lot more clicking in Maya.

BTW, you can't change topology without messing up your weights, so you'll need to or save your weights by global position with an script like doraSkinWeights, or duplicate your mesh and keep it as a weight container to copy weights to your edited mesh.

I don't think there is a way to edit your mesh and keep the original weights just like they are, like you can in Softimage. You can get only approximations with copy weights or scripts, relying in UVs or global position.

After doing all of this, now you need one more edge in your model? well, start again with the whole process.

So yes, the workflow is a mess compared to SI and is a lot more time consuming.

I disagree with Graham. You can't do GATOR inside Maya. You can get a similar final results with 10x more clicks, but it isn't the same, and you don't have a Gator op alive.

The send to Softimage is a good alternative when you can do it (basically envelope, uv and mesh modeling). Sadly, there are a lot of features that can't be translated between them like Maya crease edges or sets, or Softimage hard edges, so you'll have to re-build them. I haven't tried shapes + send to SI.

Martin

[Emilio Hernandez]

Yew Siew for delivering in Maya the Send to Softimage button for me is a lifesaver.  I do all the correctives and shapes in Softimage and send them back to Maya.  Specially when you merge two geometries with each one has shapes.   Softimage handles that amazingly.  You will get two sets of shapes in the shape manager in a single object.  Extract the shapes send them to Maya and reconnect the whole stuff.

With a script I made....

-------------------------------------------------------
Emilio Hernández   VFX & 3D animation.

[Nicolas Esposito]

So thing is or you're lucky that someone made a script in order to do something you need or you're screwed if you don't know how to script....crap...

The more I ask questions about Maya the more I feel depressed :'(

[Siew Yi Liang]

?!? That's pretty awesome, actually! Going to see if I can try that with the school's 2014 maya/xsi package for fun one of these days :D

Finally 'send to' has a use, haha!

Yours sincerely,
Siew Yi Liang

[Graham Bell]

I never said there's the exact same GATOR functionality and feature in Maya, only you can do much of the same stuff.

This is where you start to see the differences between how Maya and Softimage structures data and you look at the different Maya nodes in the dependency graph. When you looks these nodes, you can do a lot of the GATOR stuff, but I agree that it's way way simpler, easier and cleaner in Softimage using GATOR.

From: softimag...@listproc.autodesk.com [mailto:softimag...@listproc.autodesk.com] On Behalf Of Martin Yara
Sent: 25 March 2014 16:46
To: soft...@listproc.autodesk.com
Subject: Re: Merge two meshes + transfer weights - Adapting Softimage workflow in Maya