Pose Deformers and Auto Riggers

Maya: Rigging Foundations

IMPORTANT NOTE

This Page Is Old
The corrective blendshape part of this page is an old tutorial. I now use Shapes 2 which has a free personal learning edition. The foundations of this class are still correct. But the scripts used are very difficult to use in comparrison to SHAPES 2. The autoriggers have changed a lot.

Advanced Skeleton Auto Rigger

 

INSTRUCTIONS

1. Lecture
Pose Deformers
Auto Riggers

2. Practical

 

Files

Pose Reader 2013.ma(right click download)

Pose Reader 2014.ma(right click download)

Pose Deforming Big Buck – Start(right click download)

Pose Deforming Big Buck – Finish(right click download)

 

POSE SPACE DEFORMATION

Gimbal being a problem that it is, we can’t reliably map corrective blend-shapes to euler angles of our joint rotations. Enter the Pose Space Deformer. This method uses vectors rather than euler rotations and is far more reliable. The downside is there’s little implementation in maya by default. Michael B Comet released a free plugin for Maya a long time ago but it hasn’t been maintained lately though it is available for PC. See the notes below in the Pose Deformer Plugin Section. Plugins are annoying.

The other option is to use Maya’s nodes to create a Pose Reader, and then manually hook that up to a corrective blend shape. This works well and the following 3 videos show how it works.

 

Why Use Pose Space Deformers?

We use pose space deformers rather than Gimbal based deformers because of the unreliability of Euler/Gimbal Rotations. To remember what gimbal rotations are see the gimbal rotation rigging page on this site.

Keep in mind that a lot of joints only work on one plane. For such hoints Euler Based deformers are fine and actually easier and more efficient to use. However in ball joints that have a high freedom of rotation (such as shoulders) the pose deformer can come in very handy.

To see how this works see this video.

 

Pose Reader

The pose reader is a simple tool that allows us to use vectors with locators and return a 0-1 valaue perfect for blendshapes. We can see how Marco built it in the “Build a Pose Reader” Section. But we can just import the reader already built and ready to go. Here’s a look at the Pose Reader…

You can grab the Pose Reader here
Pose Reader 2013.ma (right click download)

Pose Reader 2014.ma (right click download)

 

Connecting The Pose reader to a Corrective Blendshape

To hook the pose reader to a rig it’s pretty simple.

1. Import the Pose Deformer

2. Attaching it to your rig

3. Creating a corrective blend shape or use ones you’ve already made

4. Automate the blendshape by attaching it to the pose attribute.

Build a Pose Reader

For those interested the following is a tutorial on how to make the pose deformer with Nodes in maya. No need for plugins but the process is manual and can be slow if layering many poses together. 3 to 4 should be used and only for tricky areas such as the shoulder and hips.

It can be imported into any rig. The file’s are here

Pose Reader 2013.ma (right click download)

Pose Reader 2014.ma (right click download)

The math for this setup is quite straight forward and the following tutorial by Marco Giordano does each step with Mayas nodes. Notes below

1. We need two directions in space (vectors) so we can extract an angle between them

The base is the center, goes at the pivot of our arm
The Pose is away and parented to the arm, it’s where the arm is at any time.
The Target is the place in space that we’ll hit 1 or right on to make the blendshape fire

Result 3 xyz positions

2. Get 2 vectors. Base – Target and Base to Pose
Vectors are 3 numbers that equal the distance of the Pose and Target Locators away from the Base in translate x y and z

Result:
xyz position from the base to the target
xyz position from the base to the pose

3. Get the angle between the two vectors and return an angle value (0 – 360)
Once we have two vectors we can use an angle between node to give us the angle between the two numbers. This is the dot product in maths but the node does it automatically. The angle is one digit 0 – 360 degrees.

Result: The angle between the two vectors

4. We need a user defined number which equals the cone angle
When the arm gets close to the target the value will start to trigger the blendshape. How close should that be? It’s up to you. In the tute he uses 90 degrees

Result: User defined attribute of the cone angle

5. Halve the user defined angle
The angle between is only half of the cone, so we need to halve it with a multiplyDoublelinear

Result: Half of the user defined cone angle

6. Difference between the actual angle and the user defined angle.
Now we need to find the difference of the current angle to the user defined angle.

Result: The difference between the user cone angle and actual angle between the target and pose as 0 – 1

7. Invert that number
This needs to be inverted since the math is backwards to what we want. We can do that by going
1 – x
We can use a plus minus average node.

Result: The difference number inverted

8. If a negative value make it equal zero.
Now we have an attribute which goes equals 1 when it matches and 0 when it’s at the far distance of the cone. But when it’s further away it goes into a negative value. We don’t want our blendshape to go negative, we just want it to switch off! So we need a conditional node to tell it to equal zero while in negative ranges.

We use a condition node to do this

Result: The difference number inverted, but if it’s in the negative it stays at zero

9. We’re done
Now we have an attribute that is one when aligned with the target and 0 when outside of the cone range. We can use this to plug in a blendshape to our rig.

 

Pose Deformer Plugin Notes

Here’s another good overview about pose deformers the author recommends the Michael B Comet plugin… not sure how old this post is. But it’s worth a read
http://www.tokeru.com/t/bin/view/Maya/MayaRigging#poseDeformer
http://www.tokeru.com/t/bin/view/Maya/MayaPoseDeformer

Here’s the old Michael B Comet page (tested up to Maya 8)
comet-cartoons.com/maya.html

And here’s the page which has it recomplied for 2013 2014 windows only.

 

AUTO RIGGERS FOR MAYA

Advanced Skeleton (Free)
Advanced Skeleton is the most popular auto rigger. It’s free and has a lot of features. It’s highly customisable and can even rig fish.

Commercial License costs money, I’m not sure exactly how this works, on their website it’s listed as $3000 which seems excessive. A free version is definitely available.

http://www.animationstudios.com.au/

Help Files

You can download some free rigs that have been created with Advanced Skeleton.

Angry Eunuch (right Click Download)

Dobby

Boy (right Click Download)

Snook Fish (right Click Download)

Rigging Tutorial with Non Standard Features like a fish.

The Setup Machine 2 ($99)
A very comprehensive and popular character rig for maya. Only downside is a little slow to animate, but if only 1 or 2 characters in a scene is fine. Works a treat. Pro quality.
http://www.anzovin.com/tsm

http://www.youtube.com/watch?v=WbkqOgstrongZq0

The Face Machine ($199)
A bit over kill for facial
http://www.anzovin.com/tfm

Bittner Rig 3 (free)
http://www.thomasbittner.at/_htm/scripts.htm

AB Auto Rigger (free)
http://www.supercrumbly.com/3d.php?sid=173#.Ua6qjmRga7s

http://www.olivier-ladeuix.com/blog/2010/09/05/abautorig-part-i-pyro-tutorial/

Zoo Tools Auto Rigger part of ZooTools (free)
http://www.macaronikazoo.com/
http://www.creativecrash.com/maya/downloads/scripts-plugins/animation/c/zooriggingpack-collection-of-zoo-rigging-scripts

Rapid Rig ($40)
http://www.creativecrash.com/maya/marketplace/scripts-plugins/character/c/-rapid-rig-advanced-auto-rig-for-maya–2

Rigging Toolbox ($35) And some nice simple tools
http://www.creativecrash.com/maya/marketplace/scripts-plugins/gaming-related/c/the-rigging-toolbox

BZP, PRO Biped Autorig ($40)
http://www.creativecrash.com/maya/marketplace/scripts-plugins/animation/c/bzp-pro-biped-autorig–2

BZP, PRO Cartoony Biped Autorig ($50)
http://www.creativecrash.com/maya/marketplace/scripts-plugins/animation/c/bzp-pro-cartoony-biped-autorig–2

BZP, PRO Quad Autorig ($40)
http://www.creativecrash.com/maya/marketplace/scripts-plugins/animation/c/bzp-pro-quad-autorig–2

Automatic Rigging System ($70)
http://www.creativecrash.com/maya/marketplace/scripts-plugins/character/c/automatic-rigging-system-written-in-mel–2

Jason Schliefer Style Auto Rigger (free)
http://www.creativecrash.com/maya/downloads/scripts-plugins/character/c/automated-animator-friendly-rigging

 

SUMMARY

Rigging Reels
Rigging Reels on Master Of Rigging

Instructor

Andrew Silke

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