Your title is misleading, backward actually. The idea is that the UVs are NOT locked but actually change as the vertex moves.
The technical name for what you are talking about is environment mapping. Spherical and cubic environment maps are variations of what you are describing. I once asked for world/screen mapping, another variation which would allow for all sorts of nifty NPR effects like sketch rendering.
The technical name for what you are talking about is environment mapping. Spherical and cubic environment maps are variations of what you are describing. I once asked for world/screen mapping, another variation which would allow for all sorts of nifty NPR effects like sketch rendering.