PyHenon.py

# PyHenon.py

from OpenGL.GL import *
from OpenGL.GLU import *
from OpenGL.GLUT import *
from random import *
from numpy import *
import sys

#  Initial values of width and height
width = 250
height = 250
				
def init():
	# White background
	glClearColor(1.0, 1.0, 1.0, 0.0)
	
	# Fern Green Plot
	glColor3f(0.3, 0.6, 0.2)
	
	#  Set the projection matrix... our "view"
	glMatrixMode(GL_PROJECTION)
	glLoadIdentity()
	
	#  Set the plot window range
	gluOrtho2D(-1.0, 1.0, -1.0, 1.0)
	
	#  Set the matrix for the object we are drawing
	glMatrixMode(GL_MODELVIEW)
	glLoadIdentity()

def plotHenon():
	a = 1.58
	glClear(GL_COLOR_BUFFER_BIT)
	glBegin(GL_POINTS)
	
	#x = 0.475
	#y = 0.455
	for x in arange(0,1.0,0.05):
		for y in arange(0,1.0,0.05):
			for i in arange(1,1000):
				xx = x*cos(a) - (y-x*x)*sin(a)
				y = x*sin(a) + (y-x*x)*cos(a)	
				x = xx
				
				if x > 1.0 or x < -1.0 or y > 1.0 or y < -1.0:
					break
				glColor3f(cos(i),sin(i),tan(i))
				glVertex2f(x,y)
	glEnd()
	glFlush()
		
def keyboard(key, x, y):
	#  Allows us to quit by pressing 'Esc' or 'q'
	if key == chr(27):
		sys.exit()
	if key == "q":
		sys.exit()

def main():
	#global width
	#global height
	
	glutInit(sys.argv)
	glutInitDisplayMode(GLUT_RGB|GLUT_SINGLE)
	glutInitWindowPosition(100,100)
	glutInitWindowSize(width,height)
	glutCreateWindow("3-Body Mapping")
	glutDisplayFunc(plotHenon)
	glutKeyboardFunc(keyboard)
	
	init()	
	glutMainLoop()

main()