Initialize a loop with given vertices. The last vertex is implicitly
connected to the first. All points should be unit length. Loops must
have at least 3 vertices (except for the "empty" and "full" loops, see
kEmpty and kFull). This method may be called multiple times.
Initialize a loop with given vertices. The last vertex is implicitly connected to the first. All points should be unit length. Loops must have at least 3 vertices (except for the "empty" and "full" loops, see kEmpty and kFull). This method may be called multiple times.