Repurposing MoCap Data

This project explores using Python and Rendermans custom MEL procedures to Repurpose MoCap data to be used to create new and interesting visual effects.


The MoCap data used for the renders below were obtained from Ohio State University Advanced Computing Center for the Arts and Design website.





The trails are being generated at render time via rib archives. It keeps the actual maya file very small and your project file to just as many rib files as you need to generate for the animation. Simple Geometry drives is used in place of the motion capture data and is generated as secondary geometry from the motion capture data.

View from maya at frame 161

Render at frame 161

The code to used to read the Motion capture data was written by Malcolm Kesson and the scripts and a tutorial can be found here.



Once you have the scripts and have placed them in there proper locations you can proceed to create.



1. Create a polyCube and run mocapUI; in the script editor.


2. A new set of options will appear on the polyCubeShape node as seen below.

MoCap Data File: The mocap .txt file that will be read to generate the ribs


Render As: Allows for 4 options for rendering; Points, Curves, Blobbies Volume, and Blobbies Surface


MoCap Scaling: The size of the moCap file with in the scene


Geometry Size: the size of the geometry outputted to the rib files


Trail: Creates a motion trail effect that goes as many frames back as inputted


Step Size: is how often it will place an object within the trail based on frames.



3. Browse for you selected mocap .txt file.

4. Customize your options as you see fit.




1. Go to your render settings and set your frame range and project directory

2. Create a directory named RIB_Archive in the root of your project directory.

3. Run rman genrib; in the Script Editor to generate your rib archives.

4. Now it will run through and generate the rib archives for each frame and place them in the RIB_Archive folder.

5. Once this is done you can now hide your polyCube

6. Go to RenderMan drop down, then RIB archives, create Node

7. In the RIB_Archives attribute settings select the rib archive and change the .0001.rib extension to .$F4.rib

8. Then go back to the attribute Editor go to the attributes drop down, renderman, Add Custom Shading Group.

9. Now you can add a custom shader to your RIB archives and render.


This project was a good way to ween my way into learning the basics of python and has given me a new understanding of what can be done with MoCap data. The code provided by Professor Malcolm has made the process of working with Motion capture data quite easy and has allowed for a lot of room to do interesting look development. This project leaves me wanting to experiment more with motion capture to create some more interesting pieces as well as want to further explore learning python as I can see it being a very useful tool in the future.