The vector function vaxis_rotate(A,B,F) generates "-nan"
for x, y, and z if B = <0,0,0>. Modifying x,y, or z by adding
a small amount ( .0001 ) is a partial work-around.
Attached is a simple reproduction.
If this isn't a bug, but just a mathematical "thing", I'm sorry to have
taken your time.
Thanks!
