Thanks for looking into it. That makes sense.
Maybe the particles just shouldn’t be pickable but .isPickable would be set to the true on the Mesh returned by buildMesh()? If not, maybe we could throw an error with a message saying how to fix it (“Immutable SolidParticleSystem cannot have pickable particles. Either set updatable to true or isPickable to false. To make the mesh pickable, call mesh.isPickable = true;”)
Regarding earlier question, do you have any ideas for how to use SolidParticleSystem for this case where these are glTF models that potentially have TransformNode or meshes with no vertices?
If I use SolidParticleSystem.digest it seems to be an empty mesh and if I manually loop through child meshes with vertices & addShape or digest, the size/scale/rotations are off and the mesh takes up the entire scene