Kraken 1.2 for Fabric Engine

Posted By Eric Thivierge on June 24, 2016 06:32 am | Permalink
Early this year we released Kraken 1.1 which provided compatibility with Fabric 2.0. A lot has happened since then and this post will let you know all about the latest and greatest update, Kraken 1.2.

In a nutshell, Kraken is an Open Source rigging solution for Fabric Engine that allows you to use and define rigs and solvers that produce identical results across different animation applications. Some advantages to using Kraken include:

- Leverages Fabric Engine to give consistent results across applications
- Flexible, customizable, and extendable
- Portable rigs between Maya and Softimage
- Easy to use Biped workflow
- Node based Kraken editor
- Open Source

What's New
The updates in Kraken 1.2 focus on a new and easy Biped workflow which required us to flesh out the built-in Biped components and re-organize the libraries. Other notable changes are explained in this video and summarized below:

One of the more significant additions to Kraken this release is the new quick Biped workflow. We have fleshed out our built-in biped rig components and now have menu items to quickly create pre-built Biped guides and generate rigs from those guides too.

On top of that, rigs will now have metadata stored on them which contains the guide description (same as a .krg file) and users will be able to regenerate guide rigs from a source rig.

A new preference is available that when activated, rigs that have already been built in a Maya or Softimage scene will be deleted before rebuilding the rig. This allows users to more quickly tweak and iterate on their rigs.

The Kraken core received an upgrade with the new traverser class. This class evaluates each rig and determines the correct build order to ensure dependent objects aren't built out of sync.

Users can now connect visibility attributes to solvers too. This allows you to drive visibility of IK and FK controllers based on the IK or FK blend value of the solver or other situations where visibility of rig object's need to show and hide.

A proper Python logger has been integrated into Kraken. The logger prints messages to stdout and also to the output log window within the Kraken UI. Additionally the logger can be used to log debugging information within custom components and messages logged as warnings and errors are printed to the output log in orange and red respectively. A small feature that came out of this work is that the splash screen now logs messages live from both Python and KL so users know the progress of KL extension caching and Kraken loading.

We moved the documentation to Read The Docs which provides automatic building of Sphinx based documentation. This allows us to not only build the documentation for current releases but also provide documentation for past releases as well. As we update the documentation in our development branch, it automatically builds new versions with those updates as soon as we push them to the server.

What's Next
The next release of Kraken will be focussed on enhancing the core, automatic rig optimizations during the build process and usability improvements such as automatically rearranging nodes and allowing consecutive node connections.

You can keep an eye on our milestones in the github repo to see our plans and related issues that have been logged here:

It's Open Source, It's Free
Kraken is an Open Source project and free to everyone. We've provided a solid foundation for the system and will continue to improve on it with each new release. Involvement from the community is very welcome and we've had significant interest and contributions already from the Oculus Story Studio team. They've provided amazing feedback to help drive the direction of the system. We encourage everyone to fork the repo and take it for a spin and provide feedback on their experience.

How to get Kraken
You can download the latest Kraken v1.2 release by using the following links:

- You can download a pre-packaged Kraken release by going to: 
- You can clone / fork the repo by going directly to the GitHub page here:

Documentation can be found here: