Lynn

### Note: this comment is obsolete now. One remaining issue is that `Cone` as described in the RFC is centred at the centre of its base circle. The gizmo cone...

Oh wow, I didn't know normals could be used like that. I'll remove the `Cone`-related code from this PR.

It could be, but I don't think it should be. The issue with that is that these shapes are preferably simple. If we would implement a general prism, we would...

> First, why are we making a specific shape for triangular prisms instead of just extruding our 2d shapes? I feel that either we should do "general right prisms" or...

> What's the reason for needing both `Mut` & `ResMut`? `ResMut` requires that `T` implements `Resource` whereas `Mut` does not. Since the methods mentioned above are only concerned with `Resource`s...

Can you mark 3d grid #12430, dotted lines #12394 and line joints as resolved please?

> I'm not familiar enough with WGSL to comment on how good the exact implementation is, but is there a way you could add tests for these methods that compare...

> I'm pretty sure this is wrong. Just multiplying the normal by the scale does not take non-uniform scaling into account properly, and can lead to the normal no longer...

> Speaking of which, the following two lines are equivalent. > > ```rust > let scaled_normal = (normal.xyz * scale.yzx * scale.zxy).normalized(); > let scaled_normal = (normal.xyz / scale.xyz).normalized(); >...

I am also not sure that tangents are correctly calculated either. I *think* that tangents should just be multiplied by the scale and not the covector scale. I am not...