[Zbrush] Complex character posing ?

Renaud Galand

Hey guys,

I’m about to start this long and painful(?) process called “posing a character in Zbrush with a lot of subtools” (with my pirate model). It’s the very first time I’ll do this on a highpoly model and I’d be interested to know which technique works for you the best. After picking informations here and there on the web, I found three solutions so far:

- Using Transpose master and the TposeMesh: This is the only method I tried so far and I found it pretty hard to work with. The way you have to add subtools in your “selection” with ctrl + click drag ‘n drop on ALL subtools you want to add to you selection seems very painful to get a “global” and clean falloff selection. I found myself fighting with the selection of each subtool, then loosing the whole selection, etc. I should maybe dig in a bit more, but I’d love to see a temp “subtool merging” during the time you’re doing the rig. This way you would have to deal with just one simple and global mask selection for every objects !

- Using Zsphere Rig: Didn’t find any real walkthrough on it and I don’t see a lot of people using it. Has it to do with the fact that this technique isn’t fully functional? (more like a hack or something?) Or maybe really not user-friendly?

- Vincent “Valh” Joyau and I played a bit with transpose master and import/export between max and Zbrush. It looks like you actually can export the mesh(es) (after the TposeMesh step), import in max (or any other 3D package) making sure you select the “multiple” mode (means that every subtools will stay and won’t be merged), apply a skeleton/skin modifier on the meshes, rig/skin and then export it back in Zbrush without any big problem. I still need to investigate on this method, because I wouldn’t want to rig the whole character and get a typical mesh explode in Zbrush at the end (referring to the import/export thread on PC, where I mentioned that for some reason, when I use max, sometimes I get my mesh exploding in ZBrush, sometimes not, and I still don’t know how to fix that…).


Anyways, I’d be more than happy to have your thoughts about this.

Thanks !

-Renaud

Frump

You can definitely merge your subtools using subtool master. I definitely would before posing. However after merging you are only left with exactly the divisions of the subtools you merge and lose sub-d level control. I'm also not entirely sure if it's possible to break them back up.

Being able to merge should help you a lot, just make sure you're done before you pose or else you might want to tweak something and then have to pose again!

MoP

Isn't that what Transpose Master is for, Frump? It automatically merges all your subtools at lowest sub-d level for posing.

Personally for a complex character, if you think transpose master is gonna be too much effort, i'd probably just export the tpose mesh and try rigging it in Max or whatever. Do some test re-exports before you start rigging properly just to make sure the mesh still "survives"

James Edwards

I would think GoZ might help with this as far as keeping your vert order intact - once it is available for max anyway. I can't see why you wouldn't be able to rig each piece independently in the 3d app and totally control the posing at the lowest level and not have to merge anything. I should try this at work in fact with modo...

Mongrelman

Aye, transpose master should merge it all into one mesh as MoP said.

What I tend to do is tpose master to make one mesh, then auto polygroup that and mask of parts as I need, posing the rest. Then when done, just finish tpose master.

pior

What about .... converting everything to a mesh built for displacement mapping, and pose that instead? That should avoid all the typical workZarounds ...

Joao Sapiro

i dont know if zbrush has that feature , at least it exists in mudbox that you export the lowest subd to max , edit it out repose it and then import as layer and it would preserve all the subd levels and be posed the way you want, but for alot of subtools would be some time sorry if i cant help much

MoP

Johny: That's what Transpose Master does

Renaud Galand

Thanks for all the answers guys.

Frump : what MoP said ^^ Transpose master is temporary "grouping" the meshes in one single mesh (instead of a real seamless merge) but still keep all objects separate when it comes to make the mask selection (or maybe I'm missing something here?)

MoP : Looks like this solution is the one, here thanks for "securing" it ^^

Gwot : I directly thought about GoZ and especially WHY they didn't add a max support for the first version of the plugin... *cry*

Mongrelman : yeah I tried that and it's basically how you have to deal with this plugin, but when you have bunch a VERY small pieces such as cloth attaches, rivets, etc. it's really a nightmare to add like 40 elements to your selection just to rotate the arms a little and redoing it each time you want to tweak a part of your mesh (+; the selection system is pretty laggy and not really accurate with smaller pieces). If at least Zbrush had the option to save masks and name them, this way you would need to do it the first time and that's it.

Pior : I'm not sure to understand your solution. But in my case, I wouldn't bother if it wasn't for a 3D print. But the company (ownage.com) need a .ztl file with the highpoly character so I need to end up in Zbrush and keep all my subdivision levels.

Johny : yeah I remember using "import as layer" when I was using mudbox and I never had any single import/exort problem with it, but I'm "stuck" with Zbrush on this one ^^

anyways, I will keep you updated

Frump

I haven't really used Transpose master much and I misunderstood, it sounded like it wasn't grouping. So by answering your question faultily I suppose I learned something.

Mongrelman

Aye, t'is a pain indeed, especially if you have to keep changing the pose. Best I can think of is to just auto polygroup it, then hide the large parts so you are left with the small ones (and whatever else you want) and then 'group visible', so that way they are essentially just one selection. But I don't think those polygroups would remain if you leave and re-enter tpose master And topology masking won't work properly.

Have to say, I'm curious about exporting the combined mesh, posing with a rig and importing that back in. Theoretically it should work, but I get the same problem as you where sometimes meshes explode when you take them back into zbrush, despite doing the same thing as with other models that came back in fine.


Have you tried using subtool master to actually merge bits together into one subtool before using tpose master. You should be able to reconstruct subdivision levels with that.

It would save selection time, but make the model more of a pain to sculpt.


Another idea, though again an akward workaround, would be to combine subtools together, do a quick and dirty uv map and make textures that act as masks for the various parts. Then you could load the appropriate texture and 'mask my intensity'.

'fraid I don't know a sane way to go about this problem

Renaud Galand

All good suggestions Mongrelman ! But it looks like exporting the TposeMesh in max, rig and then re-exporting is working like a charm so far ! I was a bit affraid about having different (random) vertex count each time transpose master was doing the process (TposeMesh), but it doesn't. So basically, I can close both max and Zbrush and come back on the rig later if I want to. All I need to do just re TposeMesh my mesh in Zbrush and reimport a pose using my rigged mesh from max and it seems to work at every import !

Complete walkthrough using 3D studio max 9 and Zbrush 3.1 :

1. Highpoly loaded in Zbrush
2. Transpose Master > TposeMesh
3. Exporting the "merged" lowpoly (lvl0) mesh from Zbrush
4. Importing the mesh in max making sure the "multiple" mode is selected (!). For my test I just checked "rotate model" in the obj options (no Uvs yet). Having "multiple" mode checked will keep all subtools as seprate objects which is a must have to be able to reimport back the mesh(es) in Zbrush.
5. rigging/skinning/pose the mesh in max
6. exporting as obj from max using the classic obj setup (quad, etc)
7. importing back in Zbrush
8. Once the pose is imported in the TposeMesh, just press the other transpose master button to come back to your highpoly

Mongrelman

Good stuff, glad to hear it worked.

Have you tried using the pose as a morph target? I was wondering if you could tposemesh the model, then save a morph target before you export to max. So when you import back into zbrush the pose will be a new morph target, so in theory you could just tposemesh your model and switch between the base pose and the new pose.

MoP

Hmm, this rigging workflow is even nicer too, because using tools like Max's "Skin Wrap" (or Maya's "Copy Skin Weights") you could change your subtools in ZBrush at any time, add or remove meshes, re-generate the TPoseMesh, then export it and copy the weights across from your rig, providing no large-scale proportions changed.
So it all stays quite editable and flexible.