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