Creating an animation rig in Blender: Difference between revisions

This tutorial shows you how to create the [http://mods.oni2.net/node/388 animation rig for Blender] (made by geyser) from scratch, with some improvements.

The purpose of this rig is to give us much better tools to animate, compared to our [http://oni.bungie.org/forum/viewtopic.php?pid=23698#p23698 previous process in Softimage XSI] by EdT, which allowed us to animate exclusively with Forward Kinematics. While FK may work for simple, short animations done on characters with a small amount of bones, it does not work well for Oni characters and animations, as it's too labor-intensive and inefficient.

==Prerequisite tutorials==

Blender Character Rigging overview showing that you can create a Rigify rig in less than a minute at 5:43, and also rig a character while at it:

* [https://www.youtube.com/watch?v=p6PYKyxR0aY Animating with IK and FK]

Basics of using Rigify:

Changing Rigify Custom Shapes and Widgets:

===Tracking constraint tutorials===

These explain constraints like Damped Track which are used by Rigify – you can skip this if you want, but it might give you a better idea of how Rigify's MCH (Mechanical) layers work, or come in handy in the distant future; other than that, you don't need to know them to animate for Oni:

* [https://www.youtube.com/watch?v=5FK4jDCAOkk Camera Track To vs Damped Track Constraints | Pros & Cons Explained With Examples | Blender] by 5 minutes Blender

===Tools and relevant tutorials===

* [https://docs.google.com/document/d/175uJGklYASAgrFjxuUG4-kJRDoMTjjP7GvNxSj1GscU/edit '''Oni-Blender tutorial'''] by EdT. Please read this in entirety to know likely-to-happen issues and refer to this as your guide for OniSplit commands relating to Blender.

===Assorted issues in Blender===

Here is an overview of how the rig works: As stated before, our previous animating process was limited to FK only, which is inefficient for Oni. So instead we desperately needed an IK/FK capable rig, to which we would be able to snap a character, so we could animate him/her.

The rig uploaded on Oni Mod Depot contains three Konokos by default: One T-Posed Konoko and two animated ones, all stored in their own collections. The T-Posed Konoko is there because it was easiest to build the rig off a T-Pose, while the remaining two ones, stored in Pose 1 and Pose 2 collections, is where you are supposed to store your animated characters, to which you can Pose Match, and thus check if Pose Matching works as intended.

# Import the animation you are using as a starting point.

## If you did point 3, apply the textures on the animated model.

# Using the Pose Matching functionality, constrain the rig to the imported animation (Set the IK-FK sliders on rig limbs to 1, as Pose Matching works only through FK controllers)

# For each frame that you want to remain in your animation, while having all the bones selected (or the ones you want), press Ctrl+A, select Apply Visual Transform to Pose and keyframe it.

# '''Make your animation.'''

# Export the animation as a DAE.

For detailed explanation of the required OniSplit commands, please refer to the '''Oni-Blender Tutorial by EdT''' listed in the '''Tools and relevant tutorials'''.

# Using OniSplit, export any character you want as a DAE (-extract:dae) using -noanim (T-Pose) and -blender arguments.  

# Using OniSplit, export any two animations as an XML (-extract:xml) using -anim-body (lets you specify the character you want) and -blender arguments.

## You should get '''one DAE and an XML file for each animation, totalling four files.'''  

# Import the -noanim model into Blender first ('''MAKE SURE YOU CHECK THE ''Import Unit'' BOX''', otherwise you will import the model with arbitrary units which will break everything and will be basically unadjustable later)

# Import the animations into Blender ('''ALSO MAKE SURE YOU CHECK THE ''Import Unit'' BOX EACH TIME''')

# Create three new collections in the Outliner, name them ''T-pose'', ''Pose 1'' and ''Pose 2''. These three collections allow you to quickly hide the respective models from the Viewport using the eye icon in the Outliner.

## Move the T-Posed model to ''T-pose'', and move ''.001'' and ''.002'' animated models to ''Pose 1'' and ''Pose 2'' collections respectively.

# At this point, your scene should look as shown in the screenshot on the right.

==Adjusting T-posed model's Z location==

At this moment the T-posed model is sunk to the ground. That's because the pelvis location is set to 0,0,0. All of the animations in Oni have their heights adjusted [[XML:TRAM#List_of_tags.2C_types.2C_and_flags|(through the <Height> tags)]] so that the pelvis is roughly at Z ~ 0.9, so that the characters appear standing on the floor instead of, again, sinking into it. For this reason, we want to adjust the position of the pelvis so that the feet soles are aligned with the floor.

# <li value="10">Adjust the Z position of the T-posed model's Pelvis in one of the two ways:</li>

## The 3D Cursor snapping method:

### Select one of the feet in Object mode.

|}

# Add a Basic Human Metarig  to the scene. ( Add Menu / Armature / Basic / Basic Human (Meta-Rig) )

## Scale the rig by 10 or so that it's roughly the size of the character.

## Open Viewport Display,

## Check ''In Front'' box to make the metarig easier to select when your Viewport is in Solid or Material Preview shading modes,

# Remove the following bones from the Metarig:

*pelvis.L

|}

{| class="wikitable"

# <li value="21"> Remove ''rig type'' on the ''spine.004'' bone.</li>

# Enable the ''Connect chain'' checkbox on the ''spine.003'' bone.

# Set ''pivot_position'' on the ''spine'' bone to 1.

# Enable the ''Custom Pivot Control'' checkbox on the ''spine'' bone.

|}

# Switch to Object mode and using the Snapping Cursor to Active, and Snapping Selection to Cursor in the Snap menu (Shift + S), keep snapping cursor to model's body parts, selecting the Metarig, switching to Edit mode, selecting the appropriate bone and snapping it to 3D Cursor. '''I believe it is intuitive which bones should be snapped to which body parts, therefore there is no need for a table describing that, with the exception of hints on what should be done about spine.004, hand.L, hand.R, toe.L, toe.R, heel.02.L and heel.02.R.'''

## There is actually nothing you need to do about the heel bones, leave them as they are.

## In order to keep the toe bones aligned and properly positioned, do the following for each toe bone:

### Select the foot in object mode,

# <li value="37">Copy the constraints to all of the remaining body parts.</li>

# Add a ''Copy Location'' constraint to the ''Pelvis'' and:

## Set the ''Target to ''rig'',

# <li value="40">Now we need to fix the folded pose. This is done through a set of Empties with specified rotations, which are added to the rotation of each body part through the ''Copy Rotation.001'' constraint (this is also why the Mix of that constraint was set to ''After Original'').</li>

## Create a new collection in the Outliner called "''Axis Correction Empties''".

[[Image:AxisCorrectionEmptyPlacement.png|200px|right|thumb|Proposed Axis Correction Empties' placement]]

::#<li value="4"> In your Viewport, open the Viewport Overlay and enable Relationship Lines. These are the lines that will show you lines from constrained objects to their targets. They will give you a better sense of how body parts are copying rotations from the Empties you are about to make. You can also turn Relationship Lines off at any point if they're making the scene hard to read.</li>

[[Image:RigCharacterConstrained.png|600px|right|thumb|Expected result by the end of this header]]

#<li value="47">Using 3D Cursor snapping, snap ''torso'' and ''torso_pivot'' bones to the ''mid'' body part.</li>

#Reparent ''shoulder.L'' and ''shoulder.R'' bones from ''ORG-spine.003'' to ''ORG-spine.002''.

# Controller bones are now adjusted, and we can move on to ORG and MCH layers. Select the ORG layer (31), reparent the bones and set their ''Connected'' box according to the table below. '''x''' means no change is needed.

# With X-Axis mirror enabled, select the MCH-forearm_ik.R bone and extrude it perpendicularly to the axis of the arm. You should now have the MCH-forearm_ik.R.001 and MCH-forearm_ik.L.001 bones. These bones are needed for the wrist snapping function which we'll implement later.

Now's the time to edit and add bone constraints.

==Changing custom shapes of rig controller bones==

We're getting close to the end. There's still a bit of work to do, but all that remains relates to the rig controller bones in Pose mode.

#Select the tweak_spine.001 bone:

## Set the Scale to 1.5.

## Disable the ''Scale to Bone Length'' checkbox.

<pre>        props.bones = '["upper_arm_ik.L", "upper_arm_ik_target.L", "hand_ik.L"]'</pre>

Also, replace <code>'''YOURRIGID'''</code> with your <code>rig_id</code> from point 71.

#<li value="74"> Find the following line:

<pre>        props.bones = '["upper_arm_ik.R", "hand_ik.R", "upper_arm_ik_target.R"]' </pre>

<pre>

##Add ''three'' Copy Rotation bone constraints, and move the one without the suffix to the bottom of the list (so the order of the bone constraints going from the top to bottom is ''Copy Rotation.001'', ''Copy Rotation.002'', ''Copy Rotation''). ''Copy Rotation.001'' and ''Copy Rotation.002'' will be used for pose matching, ''Copy Rotation'' will be used for axis correction.

##In the ''Copy Rotation'' constraint, set the ''Mix'' to ''After Original''.  

##Add a driver to the ''Influence'' of each ''Copy Rotation'' constraint in accordance with the table below:

{| class="wikitable"

#*foot_fk.L

#*foot_fk.R

#Add two ''Copy Location'' constraints to ''torso'' and ''torso_pivot'' bones, and make sure they're named ''Copy Location.001'' and ''Copy Location.002''.

#Copy Influence Drivers from any of the bones in point 96 and paste them into the ''Influence'' of ''Copy Location'' constraints in ''torso'' and ''torso_pivot'', in accordance with the numbers of bone constraints (e.g. copy the driver from ''hips''' ''Copy Rotation.001'' Influence and paste it into Influence of ''Copy Location.001'' in ''torso'' and ''torso_pivot'').

|}

#<li value="100"> Select any FK (green) bone and set the IK-FK slider to 1. Do this for all four limbs. This has to be done because pose matching works only through FK.

# Congratulations! The rig is now ready to be used.

[[Category:Modding tutorials]]