The big picture of Q3's curved surfaces?

Can someone give me the big picture of Quake 3 curved surfaces method? I actually found a way (expensive to be used) playing with the normals of some faces (dynamic normals).


The rounded faces are modeled and stored as
some kind of non-flat primitive. Most used
are cubic splines and bezier splines, of
which I like bezier better. (The splines are
actually 2D splines which generate a 3D

When you render your patch/primitive, you
decide how many triangles to tesselate into,
typically based on the distance from the
viewer, and plug the spline control points
into the surface equation for each generated
intermediary vertex position. Then just spit
out triangle strips and let 'em rip!