# L-5 MCS 260 Fri 22 Jan 2010 : turtlecolors

# The script below illustrates turtle geometry 
# and the (r,g,b) color triangle.

from math import cos, sin, pi
import turtle

a = 2*pi/3    # angle to draw a triangle
r = 200       # radius of the enscribed circle
c = 80        # radius of the colored circles
# first we draw the triangle
turtle.up()
turtle.goto(r,0)
turtle.down()
turtle.goto(r*cos(a),r*sin(a))
turtle.goto(r*cos(2*a),r*sin(2*a))
turtle.goto(r,0)
ans = raw_input("enter a character to continue ...")
# at the corners we put primary rgb colored disks
turtle.tracer(False)
turtle.up()
turtle.goto(r,-c)
turtle.down()
turtle.begin_fill()
turtle.color((1.0,0.0,0.0),(1.0,0.0,0.0))
turtle.circle(c)
turtle.end_fill()
turtle.up()
turtle.goto(r*cos(a),r*sin(a)-c)
turtle.down()
turtle.begin_fill()
turtle.color((0.0,1.0,0.0),(0.0,1.0,0.0))
turtle.circle(c)
turtle.end_fill()
turtle.up()
turtle.goto(r*cos(2*a),r*sin(2*a)-c)
turtle.down()
turtle.begin_fill()
turtle.color((0.0,0.0,1.0),(0.0,0.0,1.0))
turtle.circle(c)
turtle.end_fill()
ans = raw_input("enter a character to continue ...")
# then we draw the combinations at the edges
b = pi/3   # smaller angle for 6-gon
s = 100    # to put circles on edges of triangle
d = 40     # radius of the secondary rgb colored disks
turtle.up()
turtle.goto(s*cos(b),s*sin(b)-d)
turtle.down()
turtle.begin_fill()
turtle.color((1.0,1.0,0.0),(1.0,1.0,0.0))
turtle.circle(d)
turtle.end_fill()
turtle.up()
turtle.goto(s*cos(a+b),s*sin(a+b)-d)
turtle.down()
turtle.begin_fill()
turtle.color((0.0,1.0,1.0),(0.0,1.0,1.0))
turtle.circle(d)
turtle.end_fill()
turtle.up()
turtle.goto(s*cos(2*a+b),s*sin(2*a+b)-d)
turtle.down()
turtle.begin_fill()
turtle.color((1.0,0.0,1.0),(1.0,0.0,1.0))
turtle.circle(d)
turtle.end_fill()
# to prevent the turtle window from disappearing
ans = raw_input('hit enter to exit ...')