RE: [Algorithms] Scaling Models

[Peter W. <Pet...@vi...>]

<snipped stuff about scaling and normals>

Just out of interest, one thing I did a while back when I needed to treat
both normals and vertex positions uniformly when applying an animation
matrix to them was set the W component of the normals to 0, whilst leaving
the W component of the positions at 1. This worked because the animation
matrix never contained a scale, and I just wanted to not translate the
normals. Is this a well-known technique that I just haven't run across
before, and is there any theoretical basis for it?

Peter Warden
Visual Sciences