FAQ

Does editing in the panel change my scene?

No. Only Commit Keys and the Key Tools write to Houdini. Everything else, including recipes, history and preview, stays in the panel. See Houdini integration.

How do I undo a commit?

Use Houdini’s Edit ▸ Undo once. A commit is one undo step on every channel it touched. Ctrl+Z in the graph undoes curve edits only.

Can I apply one curve to many channels or many keys at once?

Yes. Select keys on as many channels as you like and press Commit Keys. With Apply to each interval, the curve is applied between every pair of adjacent selected keys. See Apply To.

Why does Get Keys read only one channel?

The Ease curve is one curve. Get Keys reads the first valid channel in path order so you can start from its motion; Commit Keys can then write the result to every selected channel.

Will my keys stay where they are?

The first and last key of each interval keep their frame and value. Keys between them are replaced; keys outside are untouched, and their motion is verified unchanged after every commit.

How many keys does a commit create?

As few as the shape needs: one per knot of the curve. A default Bounce adds six keys between two keys; a default Elastic adds three. Sampled effects are fitted to a small number of keys. Use Reduce Keys to thin out existing animation.

Can I use it in hython or Houdini Engine?

The panel needs graphical Houdini, because it reads the selection from the Channel Editor and playbar.

Can I try MotionAtelier without Houdini?

Yes: open the panel simulation. It runs the shipped MotionAtelier Python package in your browser (through Pyodide; about 13 MB, downloaded once).

• Real: everything MotionAtelier itself decides. Curve editing and dragging, the generators, Motion Stack effects and their fitting, local undo, Get Keys and Commit Keys planning, Key Tools, recipes (including export and import) and history all run the product’s own code, with its own messages.
• Simulated: the panel is an HTML copy of the Qt interface, so some details of menus, tooltips and sizing differ. The Houdini scene is a small stand-in: three channels in a simplified Channel Editor. Changes are applied directly, without Houdini’s undo groups or the read-back verification, and the scene’s Undo button stands in for Edit ▸ Undo. Nothing is saved when you close the page.

Does it work on Linux or macOS?

Not in this release. MotionAtelier is tested on Windows only. See Known limitations.

Does MotionAtelier connect to the internet?

No. It has no network access, licence checks or telemetry.

Can I use it commercially?

Yes. MotionAtelier is free software under the GNU GPL version 3 or later, with an additional permission for combining it with Houdini. You may use, study, modify, share and sell it. If you distribute it, modified or not, you must provide its source under the same terms. Animation you make with it is yours; the licence does not cover it. Houdini stays under SideFX’s own licence. See LICENSE and HOUDINI_EXCEPTION.txt in the release. MotionAtelier is not affiliated with SideFX.

How do I back up or move my recipes?

Export them to a .zip, or copy the MotionAtelier folder in your Houdini preference directory. See Where your data is kept.

How do I report a problem?

Open an issue on the project page you downloaded the release from. Include:

• the MotionAtelier version and the Houdini build (Help ▸ About Houdini);
• the exact status-line message;
• any error from the Houdini console;
• the Inspect Selection report for the affected channels, if keys were involved.