;rotates any vector about the y-axis by an angle theta, where ;clockwise is from z towards x ;theta is in RADIANS!! ; ; Created by: Robert Lillis (rlillis@SSL.Berkeley.edu) pro rotate_y, theta, x, y, z, x1, y1, z1 x1 = x*cos(theta) - z*sin(theta) y1 = y z1 = z*cos(theta) + x*sin(theta) end