The easiest way to create breakdown poses in Maya.

Say you’re creating poses for your character with stepped keys, and have created key poses on frames 1 and 10.  You want to make a breakdown pose on frame 7, but you want it to favor the first pose by 70%. The following comparison shows how this would be accomplished both with and without tweenMachine.

Manual Process tweenMachine
Select all controls on the character Select all controls on the character
Change interpolation on all keyframes to linear Left-click on frame 7 in the timeline
Left-click on frame 3 in the timeline Adjust a slider in the tweenMachine interface to -70
Middle-click on frame 7 in the timeline
Set a key
Change interpolation on all keyframes to stepped

If you’re not happy with the results, you’ve got a lot of steps to repeat if you’re doing it the manual way. With tweenMachine, you simply adjust the slider and see the results immediately.  Better still, if you’ve created a custom set that controls the entire character, you can skip the first step and save even more time.

Will tweenMachine create perfect breakdown poses? Not likely, but it will get you closer to your goal a lot faster than other methods. You spend less time with busywork and more time making actual progress.

tweenMachine window

Get tweenMachine

MEL versionv 2.1.0, released 6/7/2016 Python version (beta)v 3.0.0 b1b, released 6/7/2016
  • Easily favor poses on different body parts in different ways using multiple sets
  • Organize sets in collapsable custom groups (see screen shot)
  • Control how sets and groups affect the ticks on the timeline
  • Create an overshoot pose by enabling overshoot mode
  • Adjust the UI to use sliders, buttons, or both
  • Affect only the channels highlighted in the channel box for selected objects
  • Easily work with character sets, either by using a single custom slider, or by importing character set info into tweenMachine
  • Use Maya’s “special” tick color to identify keys made with tweenMachine
  • …and more features are still coming!
Those who follow the tweenMachine Facebook page know that I’ve begun work on an overhaul of the tweenMachine code. It’s being completely rewritten in Python, which will not only allow for much easier maintenance, but will also pave the way for features that would be extremely difficult — if not impossible — to code in MEL.

Some of the features that I would like to add include:

  • The ability to change the order of sets or groups in the UI
  • The ability to customize the buttons associated with each set
  • More robust import/export capabilities
  • The ability to interactively modify the contents of a set, including moving set items between sets and groups
  • The ability to dock the tool within Maya’s interface (Done!)
tweenMachine was inspired by Doron Meir, who told me back in 2003 about a MAXScript that someone had written for him that allowed him to easily add in-between poses somewhat similar to the way he was used to doing in 2D animation. I’d been thinking of trying my hand at MEL scripting, so I offered to create a script for Maya that would accomplish the same task. A few days later, tweenMachine was born.

tweenMachine.mel/ Justin S Barrett
xml_lib.mel J. Adrian Herbez
Maya shelf icon Keith Lango

Python (beta)

Date Notes
6/7/2016 3.0.0 b1b: Maintenance release to fix an issue that prevents tweenMachine from working in Maya 2016 Extension 2
7/11/2015 3.0.0 b1a: Fixed: Overshoot mode reset properly from settings when restarting TM.  Fixed: When grabbing the global key tangent, make sure it's a string.  Fixed: If there are no curves to tween, force an empty list.Changed: Disabled toolbar opt for Maya 2013 until a fix can be found.
5/22/2015 3.0.0 b1: Initial beta release, containing only selected features ported from the original MEL version, a streamlined UI, and the new toolbar mode.

Original MEL

Date Notes
6/7/2016 2.1.0: Updated to store certain settings so that the Python version can properly read them when the user migrates
5/31/2016 2.0.9: Modified to support keyframe data on sub-frames.
11/3/2014 2.0.8: Improved selected channel parsing to handle missing node/attribute combinations, and attributes with no connected curves.
11/1/2014 2.0.7: After tweening, focus is now set to the main Maya window instead of the last active panel.
11/1/2014 2.0.6: Fixed a bug where selecting attributes in the channel box would not find the proper animCurve nodes for tweening under certain circumstances.  Changed version numbering scheme.
10/24/2014 2.05: Fixed bug that prevented group and set dialogs from working in newer versions of Maya. Fixed bug that cropped off sliders and buttons for user defined sets in newer versions of Maya
Unknown 2.04: Fixed bug related to character set support
03/27/2009 2.03: updated to support the special tick color for Maya 200X versions
09/17/2006 Shelf icon added to download package
09/12/2006 2.02: Added a tick color toggle (visible only in Maya 7 or higher). Choose whether you want to use the standard tick color or Maya's "special" tick color for keys created with the tweenMachine
08/30/2006 2.01: New character set features! Use a single slider to favor poses on the active character set, or import your character set hierarchy into tweenMachine.
08/20/2006 2.00: Major overhaul! Added sets and groups, buttons, management tools, timeline tick control, and lots of other things. See the HTML documentation included in the zip file for full details on the new version.


Sign up for the tweenMachine Breakdown newsletter to be notified of the latest tweenMachine news: bug fixes, new features, etc.  It goes out approximately once per week, and your email is 100% safe.

First Name

Last Name

Your Email

Please leave this field empty.