alteredq/three.js — comment on commit baf0f65e1db76cc95e3d1a3cf759861b807fa177
File:  line 0
By ekitson:

> EDIT: Actually, rotation and scale needs to be there for getting proper results. If it needs to be customised I think it's up to the developer, after > all, it's not a super big method, they can just copy and customise.

Sorry, I should have been more clear. Sometimes you want to apply the rotation and scale of a matrix, but you don't want to apply the translation. For example, suppose you have a vector that represents an axis and you want to convert it to the local space of an Object3D. In that case, you only want to apply scale and rotation. Applying the translation would be very wrong. In other cases you may want to convert a vertex point to an Object3D's local space, so there you would want to apply translation.

I agree that in the end its up to the developer. I have no idea which of the two use cases is the more "common" use case. I suppose you just pick one and see how many people complain :).