ZBrushCentral

Maya, Zbrush & using sub-tools workflow

I thought I should share our current work flow. Images from meshes developed by Dotnamestudios & Peter Minister . If anyone looks at this and has improvements or developments of this work flow please share.

Level: Medium to Advanced

Workflow outline:

Use Zbrush with sub-tools to sculpt out base mesh using zspheres, retopologise the mesh inside Zbrush, export to maya to UV, detail in Zbrush, rig in Maya render out of maya ( mental ray ) or zbrush.

Why the chosen work flow ?
Doing too much outside zbrush is a little like swimming upstream, I have found the perfect mesh for zbrush can only be built inside zbrush, even the neatest quad mesh from Maya can’t be taken to as high a level as the equivilant built in zbrush. Zbrush really needs not only quads but perfect squares for high subdivision levels.
That said, if you want the ability to export and import your mesh to UV in another program or create morph targets for animation and so on you would want to be able to bring your mesh in and out of zbrush rather than have a one way work flow.
You might also want to rig your mesh in a program like maya and then render it out of zbrush.

Current issue:
A mesh containing sub-tools that has been created in zbrush cannot be exported and reimported and maintian scale and position relitive to the other sub-tools. See fig01

Solution:
The perfect world isn’t here yet so you can’t sculpt your various sub-tools to differnt levels, export them at L1 and re-import them without them jumping. If anyone can figure it out please share, the scale bug might be corrected in 3.5 but until then here is our workflow:

Mocking up shape
Do a quick twenty minute sculpt with Zspheres, to get the basic shape, then retopologise within zbrush to get a neat mesh with sensible edge loops and mesh flow.
( If you want to go much further detailing before retopologising I suggest you read up on all the threads; to sum it up it is possible, but with limited success, you can’t project very high detail methods and you are likly to experience many crashes and heart ache along the way )

Retopologise
Subject to many tutorials itself, suffice to say- think about how you want the mesh to be able to bend or animate.
Fig02

Subtools
Create or import eyes, teeth, spikes, sunglasses whatever your mesh might require but only to level 1. If you are competant in Maya it might be easier to generate simple objects requiring little sculpture such as dinosaur teeth in a later step.

Export merged mesh
Download a plug-in called Sub-tool master if you don’t already have it and merge all your subtools into one mesh. Export it as an OBJ.

Maya
Import OBJ, add rows of simple teeth or anything else you prefured not to do in Zbrush. Separate each mesh you want as a subtool into a separate UV block ( 0-1 ; 1-2 ; 3-4 ) see fig03.
The UVing is simple projection for now and is temporary. Final UVing can be done later at any stage. Personally I use a combination of Headus and Maya to create UVs and I would do it at this point; I just havn’t for this tutorial.
Merge and export

Back in Zbrush
Import OBJ into a new zbrush scene.

Tool < Polygroups < UV Group

Tool < SubTool < GrpSplit

Detail
You can now detail to your hearts desire on the various sub-tools. They can now be exported and imported to UV or rig as you require and re-import back into Zbrush in the correct scale and position.

No doubt this work flow could only be classed as a work around to avoid the scale bug, but it provides a good base to work from once set up and use the various strangths of differnt applications.

An example of this work flow solving problems is Fig04. & fig5 Here we have the many spiked dinosaur Euoplocephalus where it is clearly advantages to have the spikes as sub-tools, but in order to position it in an action pose you may choose to rig it in maya and reimport it. Certainly a maya rig is much more powerful than what you could achive in with transpose or prehaps you would want to create morph targets.

Andrew
www.dotnamestudios.com
Images copyright to Peter Minister and Dotnamestudios

Attachments

fig03.JPG

fig01.JPG

fig02.JPG

fig04.JPG

fig05.jpg

“The perfect world isn’t here yet so you can’t sculpt your various sub-tools to differnt levels, export them at L1 and re-import them without them jumping. If anyone can figure it out please share, the scale bug might be corrected in 3.5 but until then here is our workflow:”

Within your external app create cubes and place around the pieces of your mesh, as if you were placing them in the corners of a large bounding box…8 cubes all up. Combine these cubes then duplicate as many times as you have seperate meshes.
Then take each set of cubes and combine them with each individual mesh.
Export each piece (cubes combined with mesh) and import into zb.

The problem you are finding is related to how zb imports the mesh, with a bounding box each piece has exactly the same center pivot and scale.

Delete the cubes in zb after all is imported and now you have a non linear workflow.
:wink:

Dorling Kindersley set out to create the new da-facto book on dinosaurs and to that end we among the 3d-agencies to be commissioned to do digital recreations under the watchful eye of some of the worlds Leading palentologists.

A selection of final examples can be seen at www.dotnamestudios.com

It was an interesting project and a great challenge for Dotnamestudios to produce 94 rigged and rendered animals between December and April. Many of the animals need to be in environments and all the animals had to be OK’d by various fastidious leading paleontologists. There were only 4 people producing the illustrations and it meant a great deal of hard work for those involved. namely Peter Minister, Wimpie Meyer, Michelle Tyson and myself Andrew Kerr.

Pipe line:

Initial reference needed to be sourced from or OK’d by the Paleontologist overseeing the particular animal. Originally Peter was supplied the base mesh but he soon showed it was faster for him to mock it up inside Zbrush and then either myself or Wimpie would do mesh clean-up in maya, add a few edge-loops, remove null-planes ect…and then UV the mesh using Headus and hand it back to Peter. Peter would then do an initial fairly quick pass and send it to the Paleontologist for inspection. New information and interpretations of dinosaur skeletons is continually evolving and there would invariably be a few passes before it was rubber stamped.

As soon as be had the basics down such as number of toes correct and overall body form, either myself or Wimpie could rig the mesh in Maya using TSM at a low level of detail. In the mean time Peter could take it up to level 7 and add all the little bumps and scratches. I tried to keep colour decisions away from Paleontologists as they are generally fairly unimaginative and the truth is, nobody really has a clue what colour of these animals were, I generally turned to the more colourful birds and reptiles for a colour palette and avoided elephant grey as much as possible.

Peter laid out the initial colour system in Zbrush and then myself or Michelle Tyson worked on refining the pelt in a combination of Photoshop and Maxxon’s Body-paint to add age, scars and bumps, inner mouths ect…as well as extracting and working on diffuse maps.

A variety of stock shaders were used in Maya for teeth, claws and eyes and the final animal was rendered out in passes with mental ray. DK commissioned us to do approximately 45% of the animals in environments which again needed be OK’d by the paleontologists.
Grass and other plant life that had not yet evolved had to be digitally removed by myself or Michelle Tyson.

Rendering was handled by Wimpie while I did all the compositing in photoshop. Layers and layers is the secret and seldom was there less than 50 layers per scene. Background imagery came from a variety of sources of personal staff photos and purchased images, before we tried to put the animals in as convincingly as possible.

DK were supplied with with final Tiffs or in the case of the dinosaurs on a white backgorund, a layered PSD with shadows on a separate layer.

A big thank-you to all those who put a lot of work in:

The rendered Dinosaur images were produced by DotnameStudios but all rights were signed over at delivery to Dorling Kindersley under Peason Education who now own the copywrite.
Models are all copyright of dotnamestudios.
Zbrush Artist: Peter Minister
Maya Artists: Wimpie Meyer, Andrew Kerr
Shave and a Hair-Cut: Andrew Kerr
Texture Artist: Michelle Tyson
Project Director: Ina Stradins
Paleontologists: Darren Naish
Robert Owens
Chris Duffin
Donald Prothero
Andrew Milner
Steve Brusatte
Dave Hoone

Andrew Kerr
Lead Artist; Dotnamestudios

Attachments

CoverSmall.JPG

After much despair over the last few weeks and several tickets to pixologic, the best way to do the maya thing seems to be to export to maya before you do all of your sculpting.

For example, if you rough out the geo for your character in ZB, then export it to maya, work out the scale and position for each piece, then bring them all back into ZB, the scale issue is solved. The trick seems to be working this out early enough as well as taking note of the export settings (scale, offset) incase these numbers go crazy along the line you can always change these values back to where they will line up in Maya again.

It’s not ideal when you just want to ho in and start sculpting, but since I started doing this I have’t had any problems. If I decide to add any new objects, I take them into maya, match the scale and position (if they are off) and then freeze them out and re-import to ZB. Seems to work.

When retopologizing, keep using the maya scene as a reference point to make sure things are scaled properly.

btw, if you want serious efficient speed with retopology, look into Topogun and NEX for Maya. insanely fast compared to Zbrush.

hi…
The problem I have is related to how zb imports the mesh, with a bounding box each piece has exactly the same center pivot and scale.
Please suggest me about it
thanks

i want to know if i can rig the model in zbrush and then export the model with the rigging to maya cz its gonna be easier to make the rig in zbrush and gonna save time thx so much for helping me