📦 Bundle size

Full ESM build, minified and gzipped.

🌳 Bundle size after tree-shaking

Minimal build including a renderer, camera, empty scene, and dependencies.

Does that mean the new approach enables performance improvements (probably depending on the input data)?

Does that mean the new approach enables performance improvements (probably depending on the input data)?

Correct.

@mrdoob @Mugen87 @WestLangley I just stumbled upon this change and unfortunately this breaks the usage of SLERP for extrapolation (t outside 0 < t < 1). We were using this before and it worked very nice but in the current way this doesn't work anymore. Do you see a chance to adjust this allow extrapolation again as well?

@maxuai Yes. I'll file a PR.

@WestLangley Just to give some more background what we are using this for: We are rendering 3D bounding boxes in the context ground truth labeling.
The SLERP implementation is used to extrapolate the rotation of a box (e.g. wrapping a car) for a future point in time.

Simplified example:
When such a box has a roll of 20° degree at a timestamp 0 and 30° at a timestamp 500ms the extrapolated value for a timestamp 1500ms would be 50°.

To achieve this the degree value is converted to a radians/Euler (degree * (PI /180)) which is used to create the quaternions. The factor t in this example is computed by taking the timestamp of the target point in time minus the timestamp of the previous point in time timestamp, divided by the reference point in time timestamp minus the the previous point in time timestamp: (1500-500) / (0-500) = -2

When applying the SLERP to a clone of the box at timestamp 500ms with the factor and -2 and qb = the box at timestamp 0ms you get the 50° (after converting everything back to degree).