(transform-incr objetoID centerID frameID [rotate|translate|translate-scaled|scale] x y z [origin|bbox-center] [dt [smooth]])dt argumento is present,
the objeto is moved at each time step such that its average movimento
equals one instance do movimento per dt seconds.  E.g. 
  (transform-incr  World World World  rotate  6.28318 0 0  10.0)
rotates the World about its X axis at 1 turn (2pi radians) per 10 seconds.