"""
Program "Lissajous Explorer" by Erik Nelson, (c)June 2007
This is a program written with Python and Tkinter, which explores Lissajous 
figures.

The pitch and phase of the sine wave that drives the vertical coordinate are adjustable with controls on the left and the controls for the horizontal coordinate are on the bottom. The phase slider is scaled so 0 to 100 is a half wavelength.

The two sine waves are functions of the variable t, which stands for time.

buttons: "erase" just clears the screen.
"t=0" resets t to zero and clears the screen.
(this is needed because if you left it running for a long time, t would get huge and we would get weird floating point rounding errors. I have not seen this happen yet though.)
"bye" quits the program.

"""

from Tkinter import *
from math import *

t=0


xcenter=250
ycenter=250
xheight=200
yheight=200
xpitch=.01  #This value is not used, but I still need to declare the var
ypitch=.01  #This value is not used, but I still need to declare the var
xoffset=.5  #This value is not used, but I still need to declare the var
yoffset=.5  #This value is not used, but I still need to declare the var

def xcoord(T):
	return xheight * sin( xpitch * T + (xoffset * pi ) ) + xcenter

def ycoord(T):
	return yheight * sin( ypitch * T + (yoffset * pi ) ) + ycenter

class Ani(Frame):

	def printit(self):
		print "hi, my t is equal to",t

	def tick(self):
		global t
		t=t+1
	
	def createWidgets(self):
		self.QUIT = Button(self, text = 'bye', foreground='red',
			command=self.quit)
		self.QUIT.grid(column=3, row=5)

		self.ZERO = Button(self, text = 't=0', 
				command = self.zerot)
		self.ZERO.grid(column=3,row=2)

		self.ERASE = Button(self, text = 'erase', foreground='red',
				command = self.clear)
		self.ERASE.grid(column=3,row=1)

        	## The ypitch control
       		self.yptch = Scale(self, orient=VERTICAL,
			label="y_pitch", from_=1, to=100)
		self.yptch.grid(column=1,row=2)
		self.yptch.set(50)

       		## The xpitch control
       		self.xptch = Scale(self, orient=HORIZONTAL,
			label="x_pitch", from_=1, to=100)
		self.xptch.grid(column=2, row =5,)
		self.xptch.set(30)

		## The x offset control
		self.xofst = Scale(self, orient=HORIZONTAL,
			label="x phase offset", from_= -100, to =100)
		self.xofst.grid(column=2, row=6)

		## The y offset control
		self.yofst = Scale(self, orient=VERTICAL,
			label="y phase offset", from_= -100, to =100)
		self.yofst.grid(column=1, row=3)


		self.draw = Canvas(self, width=500,height=500)	
		self.draw.grid(column=2, row=1, rowspan=3)




	def dotter(self):
		global xpitch
		global ypitch
		global xoffset
		global yoffset
		xpitch = .001 * self.xptch.get()
		ypitch = .001 * self.yptch.get()
		xoffset = .01 * self.xofst.get()
		yoffset = .01 * self.yofst.get()
		
		self.draw.create_rectangle(xcoord(t), ycoord(t), 				xcoord(t) +1, ycoord(t)+1, fill="black")
		self.tick()
		#self.printit()
		
		self.after(1, self.dotter)

	def clear(self):
		"""self.draw.create_rectangle(
					1,1,499,499, fill="white",
					outline = "white")"""
		self.draw.delete(ALL)

	def zerot(self):
		global t
		t = 0
		self.clear()

	def __init__(self, master=None):
		Frame.__init__(self, master)
		Pack.config(self)
		self.createWidgets()
		self.after(10, self.dotter)



ani = Ani()

ani.mainloop()