"""
 random_circles.py

 Draw many circles which vary somewhat slowly in location, size, and color.

 Jim M | cs.marlboro.college | Sep 2018 | MIT LIcense
"""

from graphics import *
from random import randint

n_circles = 1000

window_size = 800    # pixels, width & height
initial_radius = 20  # pixels

position_shift = 80  # pixels, max random location change
radius_shift = 10     # pixels, max random radius chnage

initial_red = 200
initial_green = 200
initial_blue = 200

color_shift = 4    # max random color change

def circles():

    window = GraphWin("random circles ...", window_size, window_size)
    x = window_size/2
    y = window_size/2
    radius = initial_radius
    red = initial_red
    green = initial_green
    blue = initial_blue

    for i in range(n_circles):
        
        circle = Circle(Point(x, y), radius)
        color = color_rgb(red, green, blue)
        circle.setFill(color)
        circle.setOutline(color)
        circle.draw(window)

        x = (x + randint(-position_shift, position_shift)) % window_size
        y = (y + randint(-position_shift, position_shift)) % window_size
        
        red = (red + randint(-color_shift, color_shift)) % 256
        green = (green + randint(-color_shift, color_shift)) % 256
        blue = (blue + randint(-color_shift, color_shift)) % 256

    done = input("done? ")

circles()