# Problem 2, HWK 3, PHY307 Fall 2002
# Race a yellow sphere, blue ring and white cube. Staggered by
# a distance of 2 in the z direction, they breathtakingly race to the
# right.
#
# The 3 objects are intially created, then their positions are
# changed by adding a small amount to each objects' x position
# in a loop, whose rate is controlled by the rate() statement.
from visual import *

racer1 = sphere(color=color.yellow, z=0)
racer2 = ring(color=color.blue, z=2)
racer3 = box(color=color.white,z=4)

# for bonus kicks, draw a starting line
startline = cylinder(axis=(0,0,4),radius=0.1,color=color.red)

# prevent autoscaling, so that motion can be seen more cleanly
scene.autoscale=0
while 1:
    rate(40)
    racer1.x = racer1.x + 0.01
    racer2.x = racer2.x + 0.015
    racer3.x = racer3.x + 0.02