Mixamo to Houdini Apex Workflow

Simple Automated workflow for implementing Mixamo animations and characters in Houdini APEX based workflow.

Workflow

The HDA's and python plugin will create basic workflow which needs to be modified as per requirement. This is just a mere skeleton

Electra Base Rig is used as a reference for the workflow.

For more info see: https://www.sidefx.com/contentlibrary/electra-rig

Mixamo rigs are first mapped and renamed with respect to electra rig. Captured weight mappings are also renamed. Guide Skeletons are created based on the remapped names.(Non Destructive) Base Apex Rig is then created and the animations are then transferred.

Python Tool is used to streamline the workflow. Character and animations can be selected within the python plugin. Multiple Animations can be stacked up or looped via plugin. Previewing the stacked motion clips are available and complete apex workflow can be generated from the plugin itself

Disclaimer

I'm not a rigging artist. I have used the Apex Component Scripts from the electra rig example as reference and automated the workflow.

For more info see: https://www.sidefx.com/contentlibrary/electra-rig/

HDA Descriptions

MixamoNameRemap

 Use points sop to map the names between electra rig and mixamo rig.
 Rename the Captured Atrributes in Captured geometry
 Cleans the "name" attribute

MixamoApexConfigurator

 Create tags for Apex. Inspired from the electra rig example
 Create a Guide Skeleton procedurally with the remapped names. Modify the Guide skeletons if required.(EG: ArmPole Spacing)

ApexBipedRig

 Implements the electra inspired rig for mixamo characters

ApexTransferMixamoAnimation

 Transfer the animation clips to the new apex based mixamo character
 New animation will be added to the apex scene

Setup Instructions

Step 1:

Install all the 4 hda's present inside the hda folder. Eg: Assets --> Install Digital Asset Library --> Select all 4 HDA files --> Install

Step 2:

Create a New Tool in any shelf of choice. Name it accordingly. In the Script Tab Copy the code from "MixamoApexConverterTool.py" and paste it and accept. Eg: In Animatin Shelf --> Right Click --> New Tool --> Script(TAB) --> Paste the Code --> Accept

Python Plugin Overview

Plugin is developed with pyside2.

Characters can be loaded from file system by clicking the Add Character button.

Animation Clips can loaded from file system by clicking the Add Animations button.

N no of animation clips can be stacked the tool will extract and sequence the motion clips based on the uploaded order.

Uploaded animations can be dragged and dropped to create copy of animation to stack or deleted using delete button.

Loop value can be set to loop the particular animation for the given time.

With character and animations are provided motion clips can be previewed using the Preview button.

Preview will create only the motionclip sequenced subnet.

Apex network workflow can be created by clickin the Apex Convert button.

How To Use the Python plugin

Step 1:

Open the tool.

Step 2:

Click the Add Character button and select the character fbx file from mixamo.(It can contain animated pose but only the character is extracted not the animation).

Step 3:

Click the Add Animations button and select multiple animation fbx clips from mixamo. Order of selection is important. Make sure the animations and the character are for the same captured geometry. Animation retargetting is not handled.

Step 4:

Delete any extra animations by selecting and using the Delete key. Copy and Stack the animations using drag and drop. Use the loop count to extend the animation

Step 5(Optional):

Click the Preview button to create a subnetwork with motion clip's merged. Changed the blend values if required.

Step 6:

Click the Apex Convert button to create the apex network. Enter into scene animate node and modify the animations