Cult of Rig : Season 00 Day 010 Finishing Pedals and GodNode Components

Season 00 Day010 Stream – Finishing Pedals and GodNode Components


Pilot Season – Download


Rigging Dojo Notes:

This week we are not doing much of a breakdown, there are many details and things that you simply have to watch through the video to understand and get the most from. We will pick out a few things that we want to explain or highlight. Enjoy!

God node (Master control)

  • Drive the whole rig but doesn’t have to be in world space
  • top_top_world_ node, hidden, used by only shot final, this is the world space of your rig, the GodNode would be under it

Building the component

cult of rig god node hiearchy

  • Building a non-cyclic constraint

Connecting the God Node component in to the rig

there is a good few bits of trouble caused by the node editor not being set to sync… jump to here to see the hook up of the offset nodes

Maya name space : “underworld” and all the connective nodes between SRT nodes get assigned that name space.

On to the next video!



Get involved:

Scene used to display the functions is available at:…
Maya 2016 and up.

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Check out the calendar for up-to-date information and times

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Cult of Rig : Season 00 Day 009 Applying Math to Fix Components

The rig as you see it by the end of this session, plus a little bit of crud cleaned out, is now available at…
If you’ve fallen behind but still want to nodel with me, now you can catch up. Or just take it apart ūüôā

Season 00 Day009 Stream – Applying Math to Fix Components
“Building upon the theory established the previous day we can now flatten the rig hierarchy some more to extract the pedals from their FK only position, and complete the transform for the staff to inherit rotation.”

Rigging Dojo Notes

  • Why not make everything flat? While keeping the controls not in a deep hiearchy helps with flexablity but making a flat “component” limits the amount of control you get out of the component, in Maya you can always get worldspace from a node so making everything worldspace/flat you loose any local data you get from a hierarchy.
  • Fix the rig:
    • Graph from the output or forward from the input of the component to start walking the graph and troubleshoot the rig.
    • Matrix multiply¬†pedals_M_staff_ctrl¬† by pedals_M_staff_ctrl_srtBuffer (order matters)
      • decompose the matrix and¬† and drive the rotation of the staves_srt to fix the current rig bug.
  • Fix IK control

  • To get the IK FK blend, need to make sure both are in the same space
  • Here Raf blasts away chunks of the rig instead of trying to fix or figure out what they were doing.
  • He explores getting the pedals_M_ikPedals_projectedAngle_fnode hooked up to the same space as the FK driver.
  • There is some discussion as he rehooks up the nodes so it is a good point to watch from here
  • Tips: expression vs. nodes? try both and see what is faster in your rig but stay away from Python Nodes so they don’t play well with parallel.

Pedal settings of the IK FK attribute

  • If you name the attribute FK IK switch, then that is the order it should blend in, pay attention to those details.
  • *Q: do you alias attributes? No Raf hates them and it complicates things later on, don’t bother.
  • Some left over logic nodes from past videos Raf hooked the nodes back up to the animBlendNodeAdditive¬† weights to hook it back up like before.

Question: What about rigging like this with so many nodes vs. constraints etc, does it become complicated, but the point of this is to learn to rig with CLEAR input and Output of each component. It is easier to refactor for complex rigging.
Maya needs compound nodes (if they do) this style of rigging will scale better as it gets more complex (parallel processing for Maya)

Request: Node editor: let us grab a connection line and drag duplicate to another node for connection instead of having to click on the source node and drag the connections.

Change space of the pedals and update the rig

Fix a pedal offset bug

RDNotes:At this point in the video, Raf has to explore and troubleshoot the graph- he knows what he is doing and build the graph and still hits a problem. This is how rigging goes, it isn’t a perfect straight path to a working rig. This is what the job is, and worth watching how it works through how to fix the problem.

….to be continued in the next stream



Get involved:

Scene used to display the functions is available at:…
Maya 2016 and up.

Follow me on twitter for announcements and news

Check out the calendar for up-to-date information and times

Follow the Streams live on Twitch

And keep up to date with news on the website

Cult of Rig : Season 00 Day 008 Math Crash Course

Season 00 Day 008 Stream – Math Crash Course – Trigonometry and Matrix Mult

Trig is the study and solution of triangles…or all angles

Starting with Trigonometry as it is a basic and good place to start vs. starting with linear algebra that creates lots of extra wasted calculations.

“You hear me mention custom nodes…doesn’t mean you don’t have to use custom nodes unless you need performance, but the math part is important for foundations”


  • Right triangle is where we start (triangle with 90 degree corner)
    • degree vs. radian
      • Also the “Why” of when unitConversion nodes show up as you connect a translate value to rotation.
      • unitConversion nodes are normal maya nodes with some basic math (conversion factors) and change the type of the connection at the output (
    • Scene used to display the functions is available at:…
      Maya 2016 and up.
  • Back to radians
    • Radius of the circle¬† R=1¬†¬† means 1/2 is PI 3.14¬† so full raius is 2 PI R
    • when you see radians the start of the circle is 0, end is 2 PI, half circle is 1/2 PI
  • Degrees
    • Circle is broken in to 360 values , 0, 90, 180, 270, 360
  • The relationship between the two is PI = 180¬†¬† so if you need to convert them 3.14/180 to convert so when you look in the unitConversion node you see this math happening.

When you create triangles from a unit circle you always get hypontus of 1, simplifying calculations.

function of an angle (works in radians always works  between [-1,1]

  • Sin
  • Cos
  • Tangent ( can be infinite)

Each function has an inverse

  • arc sin
  • arc cos
  • arc Tangent

What do these do?

If we say the we get the Sin of the triangle leg, the Arc Sin will give us the Angle.

Given any axis, if you are rotating around Z for example , clockwise will be negative.¬† This isn’t great so flip the mesh around so that the rotation will be positive.

*Do follow along in Maya with the example scene and also create with Raf.

  • Build some primitives named
    • sine
    • cosine
  • We will rotate the HY transform node (from the example file) and on its rotation¬† to create an expression

skip from 30:00 to here to see 35.32 to see the expression work

in expression editor type sine.ty = sin(hy.rz) and click create

Rotate the hy node to see the SINE node translate up and down. Because the connection creates a unitConversion by default you can change the value in the unitConversion node to 1 to allow it to pass through to the SIN() in the expression with no rad/deg convert.

Next we create the cosine transform expression  cosine.tx = cos(hy.rz) so we now have our nodes translating up and down and left and right as we rotate the HY node.

Behind the scenes in Maya when you take¬† a “vector” and rotate it with Matrix Math.

If we connect the  translate X from cosine and translate Y from sine to a new transform you can see that the new Transform (say a new sphere) you will get the same action as if a parent constraint on the new sphere following the HY node.

The combination of the Sin and Cos create a translation the spears to be a rotation.

Soh Cah Toa

For any giving angle there are two sides, (legs) adjacent, opposite and hypotenuse

S(?) = 0/h  C(?)=a/h  T(?)=o/a

Law of Sin and Law of Cosin 55:30

a/sinA = b/sinB = c/sinC

Law of cosines is the foundation for IK solvers like the 2 bone solver

“I mention all of this because when ever you are using Matrices because this is what you are doing under the hood a lot”


Linear field of numbers with sides

Vector for example is a single column Matrix.

Raf gets in two a few topic tangents and you are best watching it as it is hard to note what he was talking about with all the drawing and graphics.

What happens when the Matrix is not normal? 1:15


Why is this important?



Get involved:

Scene used to display the functions is available at:…
Maya 2016 and up.

Follow me on twitter for announcements and news

Check out the calendar for up-to-date information and times

Follow the Streams live on Twitch

And keep up to date with news on the website

Cult of Rig : Season 00 Day 007 Matrix math rig clean-up

Season 00 Day 007 Stream – Cleaning the Components

“Day 7, we introduce matrix multiplication and then proceed to an uninterrupted stretch of rigging proper (yay!)
Lots of nodelling.”


What is the Matrix? 6:00 (video)

Raf hits some basics of the Matrix, the Matrix is the transform in Maya and describes what was required to move the object to where it is in space.

If you want to reverse the path of the object back to 0,0,0 this is the “inverse Matrix” will give you this path.

*order maters in how they are multiplied*  Similar to Rotate order

“Build a rig that you are not affrid to change the rig”

Implement the rig:

If the rig so far has been built correctly you can simply select all the “deform” nodes and graph them and cut the connections. (rig should stop updating the mesh after)

Don’t be afraid to detach chunks of your rig and re-hook up later.

Next hunt down any nodes that are in the connections but not named correctly


  • pedals_M_cmpnt
    • input
      • localWorld_srt¬† updated to pedals_M_localWorld_srt
  • Control graphed and¬† “wheel_M_main_ctrl_wMtx_output_fNode2” gets updated to match what the in and out connections are “pedals_M_staffworldMtx_fNode”
  • Continue to clean the graph and make sure the IK FK blend works
    • Here you need to watch closely as Raf shows a fearless editing of the existing rig nodes to prep the rig.

Build a new attribute holder

  • Create new curve shape
    • pedals_M_settings_ctrl and parent it under the pedals_M_cmpnt-controls
    • It needs to move along with the rig
      • pedals_M_world3staff_offset_srt-> pedals_M_staffworldMTX_fNode-> pedals_M_settings_ctrl
  • Add custom attribute FKIK_switch¬† and pedals_gravityAligned

We had this working before but it gets disconnected and cleaned up

  • We were using the animBlendNode_AdditiveRotation weight to rotate the node to flip the value and also do the blend.
  • Make sure animBlendNode_AdditiveRotation.output -> pedals_M_pole_srt.rotation (this still works from our process before)
  • Few more cleanup passes on some of the¬† other unnamed nodes multMatrix1, decomposeMatrix2, vectorProduct3,angleBetween node, from pedals_M_world3staff_offset_srt.¬†¬† pedals_M_localizedPEdal2staff_fNode, pedals_M_localizedPEdal2staff_mtx2srt, pedals_M_ikPedals_projectedAxis_fNode, pdeals_M_ikPedals_projectedAngle_fNode

“Don’t just copy what I do, become familiar build dexterity with the Node editor”


The next process is hooking up the logic for the connections, FKIK_switch out to Weight B on but the value needs to be flipped- Using Reverse node to flip the 0 to 1 should give us the weight swap.


FKIk_swtich to animBlendNode_AdditiveRotation.Weight A to finish the rig.

Next get multDoubleLinear node take FKIK switch attribute to its input 1 and set input 2 to -1 to flip the incoming value and hook it up to the animBlendNode_AdditiveRotation.Weight A .

Rename your nodes and clean up the graph on what you just created and hooked up.

Staves rigging:

  • wheel_M_main_ctrl_wMtx_output_fNode1.Translate -> staves_srt.Translate
  • animBlendNode_AdditiveRotation.rotate-> staves_srt.rotation
  • update name animBlendNode_AdditiveRotation¬† to pedals_M_FKIK_rotBlend_fNode

Continue clean up and end: (1:15:00)

Here Raf walks the graph and updates the names of the nodes to help make sure they make sense to the rig and do what they are doing, there are many changes here so take the time to watch this part of the video or clean up the rig names on your own.



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Cult of Rig : Season 00 Day 06 – Theory and Applied vectors, IK pedals

Season 00 Day 6 – Theory and Applied vectors, IK pedals


“More on vectors while we actually show some application, and eventually make it to hooking up the pedals’ geo to the IK pedals control in the niche of time”

“Day 6, crash course in vector math, sprinkle of matrix math, and finally, applying in Maya. IK pedals connected to the geometry in the niche of time.”

continuing from last video cult-rig-season-00-day-005-vectors

Quick catch up:

  • Shout out to animBlendNodeAdditiveRotation for angle connections without unitConvert nodes.
  • Pythagorean theorem reminder for dealing with vector length
  • |V| or ||V|| is how you might see will be an absolute length of a vector, if you read about vectors in math books
  • a unit vector is the vector compressed in to a 0 to 1 range
    if you want to scale it, normalize it first then * by value to scale it up to be longer.

How to do this with nodes: Vector scale and playing with vector math.

  • create a control transform group “pedal_ik_ctrl”
  • Add a cone polygon primitive
  • Connect the ik control to drive the cone
    • create the node vectorProduct
    • connect ik translate to node input and go output to the cone translate.
    • set the vectorProduct attribute normalize output this crates a “follow” that is limited to a range of 1 and set to “no operation” because we only want the value normalized.

How do we create the Math with only nodes?

  • interesting tip that comes up later: If you have two vectors and normalize them then do dotProduct you get the angle between them
  • Create a spherical constraint with just vector math(13:29)
    • ik ctrl node translate – vector Product-translate of target
    • To control the length is multiply the vectorProduct by a value with a multiplydivide node before the target translate.
    • If you want to lock this sphere to a single plane you need to set the axis in the mitiplyDivde node to zero.

Need to control this effect or build on.

  • dotProduct
    • ||a|| *||b||* cos¬† – if you have two normalized vectors multiplied by COS gives you an angle.
    • If your vectors are aligned (angle zero) the COS of that angle is going to be 1
      • ||b|| * COS¬† normalized gives you the magnitude(length) of the vector
  • So with out a “length node” in Maya we can use the vectorProduct node
    • pedal_ik_ctrl.translate out to vectorProduct 1 node (normalizing the value no operation) -out to vectorProduct 2nd node input 1
    • pedal_ik_ctrl.translate out to vectorProduct 2 node input 2 (with no normalizing set to dotProduct)
  • We get the result of the length of the vector
  • Condition node (if length of first vector in to “first term” ) is greater than 3 (then we want the reScaled vector from multiplyDivde node “second term” )
    multiplyDivide.output – Color if true.
    otherwise if the length is less than, use the pedal_ik_ctrl translate.
    Then take condition.out to the cone.translate.
  • This creates an “IK” like behavior by creating a limited range

RIGGING : Back to rigging the bike pedals

Raf now uses what he just worked through with the vectors to create the rigging. And updates the names of the nodes.

  • pedals_M_pedal_IK_ctrl_srtBuffer
    • pedals_M_pedal_IK_ctrl
  • pedals_M_pedal_IK_ctrl. translate->vectorProduct (no operation) – multipleyDivide


We want to have our pedals_M_pedal_ik_ctrl_srtBuffer end up in the same space as the the pedal_Mstaff_ctrl_srtBuffer + an offset

  1. parent pedals_M_pedal_IK_ctrl_srtBuffer under pedals_M_cmpnt-control
  2. world2Pedals_offset_srt->wheel_M_main_ctrl_wMtx_output_fNode2 -> pedals_M_pedal_IK_ctrl_srtBuffer
  3. create a new node staff2pedals_offset_srt that is a child of pedals_M_cmpnt- input- world2pedals_offset_srt (rename name to world2staff_offset_srt )
  4. staff2pedals_offset_srt world matrix out- to new decomposeMatrix node wheel_M_main_ctrl_wMtx_output_fNode3- srt out to pedals_M_pedal_IK_ctrl_srtBuffer

Now the IK control starts in the same place as the FK

Raf does something interesting here to drive the control points on the shape for the pedal inverse of the transform to create a visual link 

At this point Raf also digs in to Matrix math (1:00hr) to setup the information needed to create context to the nodes and rigging that he needs to do to make the IK buffer work in the rig.

*Maya uses row matrices, reading top to bottom across the matrix

1,0,0,0 x
0,1,0,0 y
0,0,1,0 z
0,0,0,1 (w) displacement from world 0,0,0

Continue the rig

  • world2staff_offset_srt
  • pedals_M_peal_IK_ctrl

New node time ( multiplyMatrix )

Take the inverse matrix from world2staff_offset_srt ->multMatrix.Matrix In[2]

and pedals_M_peal_IK_ctrl.worldMatrix to ->multMatrix.Matrix In[1]

Now decompose the multMatrix output  and drive a sphere for visualize the output of the offset we now need in order to drive our pedals.

delete it and create a cone.

parent the code under the world2staff_offset_srt for visualization of the pivot.

  • multMatrix-decompose->and attach it to the translate/rotate to check that your offset goes to the pedal location.

But we need rotations, not translate

  • create vectorProduct and set it to no operation
  • Dot product can give you both projection and angle of the vector.
  • New node (angle between)
    • multMatrix-decompose-Y and Z in to the angle between vector Y.Z and then angle.euler out to the cone to show rotation. of only Y and Z, keeping X from solving and creating a flat plane of rotation
    • To invert the value push the Euler out to animBlendnodeAdditiveRotation and – the weight so you can get the rotation angle in the direction you need.
    • ¬†To do the final rig hook up between the IK and FK¬† using the existing animBlendnodeAdditiveRotation¬† node, take and pedals_M_staff_Ctrl (our fk rig) .Rotate¬† into¬† animBlendnodeAdditiveRotation.inputb
    • then animBlendnodeAdditiveRotation.Output – to Deform-pedals_M_pole_srt
  • Now the weight value on the animBlend node will mix between the IK or FK rig system.


What does this give us?

  1. A rig that doesn’t depend on hierarchy
  2. no relationships with layers of constraints because the rigging is managed with pure math and in the DG not in the hiearchy.
  3. A deeper understanding of what Maya is managing behind the scenes when you are doing constraints and parents etc in the DAG.



Get involved:
Follow Raf on twitter for announcements and news
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Subscribe and watch past broadcasts
Cult of Rig -YouTube
And keep up to date with news on the website