Is it possible to add a setColorAt method for BatchedMesh? about three.js

[gkjohnson]

As Mugen mentioned - users can already do this by creating geometry with a color channel which is effectively how InstancedMesh worked. In order to do this in a more memory-efficient way you'd need to pack the per-geometry colors into a texture and sample them in the shader. I've provided a demo of this idea in #27170 (comment).

In short, though, I think this can be closed as a duplicate of #27203 which is really just about being able to have more granular, high performance control over the material of individual geometries.

[Mugen87]

Instancing and batching work different meaning you don't have instanced attributes when rendering a batched mesh. Having instanced attributes made it easy to implement instanced colors for InstancedMesh.

It's important to highlight that setColorAt() was added so different colors per instance was possible at all. When using BatchedMesh, you can already have different colored geometries via vertex colors.

Meaning if you use addGeometry() with geometries that hold a color attribute, you can author different colors per geometry by simply altering vertex color values.

[mrdoob]

@gkjohnson Have your ever needed this?