11/5/26

Blender 5.3 preserves animation when the axis order changes

Soft Blender

In Blender 5.3 you can change the rotation order of an animated bone or object, and the motion will not change. For example, you can switch from XYZ Euler to ZXY Euler or to quaternions. The program recalculates the rotation keyframes for the new mode on its own. Jonathan Lampel (@jonlampel) drew attention to this capability in a post on X dated November 4. In his view, the feature has gone almost unnoticed so far.

“One of the Blender 5.3 features that I see hardly anyone praising so far: when you change the rotation order, the program can automatically convert all of your rotation keyframes to the new order, so the resulting animation stays the same. That's very nice!” — Jonathan Lampel, post on X

The post itself is short. Details are given in the official Blender 5.3 release notes and in the user manual. The developers included the new command in the list of major changes in the animation and rigging section.

Where to find the command and how it works

The command is called Convert Rotation Mode. It can be invoked in several ways:

from the Object › Animation menu in object mode;
from the Pose › Animation menu in pose mode;
from the new dropdown list next to the rotation mode field;
with Ctrl+R in Pose Mode.

The list offers all of Blender's rotation modes: Quaternion (WXYZ), six Euler variants (XYZ, XZY, YXZ, YZX, ZXY, ZYX) and Axis Angle. The command processes all selected objects or bones at once, so several bones with an inconvenient axis order can be converted in a single action.

Blender 5.3 preserves animation when the axis order changes — The Convert Rotation Mode dropdown next to the rotation mode field in Blender 5.3. Screenshot: Jonathan Lampel / X

The difference from simply switching the mode is described in the Blender 5.3 manual. Simply changing the value in the mode field does not recalculate existing curves. The new command rewrites the animation curves themselves and preserves the resulting orientation over time as accurately as the new rotation representation allows. The recalculation runs across all actions associated with the selected object or bone. If a character has separate clips, for example for walking, running and idle, there is no need to convert them one by one.

A similar command used to be part of Rigify. The developers call the new command an improved version of it, and the old one has been declared deprecated. The new command is also available through Python, for objects and bones in pose, so it can be built into a studio's pipeline scripts.

What to keep in mind

The manual explicitly lists the specifics of the conversion:

after the recalculation, the animation is always fully written out for the new mode. If keys previously existed on only some of the rotation channels, after conversion they will appear on all of them;
the interpolation between keys may change. The developers call this expected behavior, because different modes describe rotation differently;
keyframe types are preserved where possible.

For cases where accuracy matters there is the Bake option. Before the conversion it places a key on every frame, and the motion is reproduced more precisely at the cost of extra keys. Such a dense curve will probably be harder to edit by hand in the Graph Editor.

The same section of the release also brought commands for copying and pasting animation in world coordinates. They work with several objects and bones at once and take the preview range, or the scene range if the preview range is not set. Pasting onto objects and bones with constraints is not supported yet.

Who will find this useful

The Euler axis order is usually changed to get away from gimbal lock on a complicated rotation or to make editing the curves of a particular joint more convenient. Previously, judging by the release notes, such a conversion required the command from Rigify; otherwise the animator was left either keeping the inconvenient order or re-keying the poses from scratch. Now a built-in command makes it possible to change the order on an already finished animation. First of all, this will probably be useful for character animators and riggers who fine-tune a rig after clips have already been made with it.

The limitations are practical too. Because of the full write-out of channels and the possible change of interpolation, after the conversion it is worth checking the key poses and curves, especially on stylized animation with finely tuned timing. Baking conveys the motion more accurately, but the curve is harder to edit afterwards. That is why it makes more sense to do the conversion before the final polish.

Community reaction

The reaction is mostly approving: users call the feature an unobtrusive but important improvement that strongly affects daily work. The main argument: recalculating keyframes when the axis order changes saves hours on already finished rigs and animations, where such an edit used to break the motion. One commenter noted that, as far as he knows, a similar capability existed earlier as well, only hardly anyone knew about it. He himself lost a fair amount of time on past projects until he found out about it. Others note that Blender 5.3 has other little-discussed but useful details as well.

“This may seem not too exciting, but it's a real breakthrough! Goodbye, gimbal lock!”
— @vopiscus_bm (X)

“The note about rotation conversion is exactly the kind of breaking-changes detail that saves hours on existing rigs.”
— @caren633881 (X)

“I only found out about this a few months ago. Apparently the feature has existed for a long time. I nearly threw my computer when I realized how many hours I had lost on other projects.”
— @swamusic_ (X)

Where do you have to change the rotation mode more often?