crop_circles_in_nodebox.py

import itertools
import math

skew(0.0, 0.0)
stroke(0.3, 0.3, 0.3, 1.0)

class ConcentricCircle(object):
    def __init__(self, x, y, radius, qty, attraction, width):
        self.x = x
        self.y = y
        self.qty = qty
        self.radius = radius
        self.attraction = attraction
        self.width = width
                 
    def draw(self):
        push()
        fill(0.0, 0.0, 0.0, 0.0)
        stroke(self.strokecolor())
    
        for i in xrange(self.qty + 1):
            strokewidth(self.width * i / self.qty)
            r = (self.radius * i) / self.qty * 2 
            r += self.attraction * (float(self.qty - i) / self.qty)
            offset = (r / 2)
            oval(self.x - offset, self.y - offset, r, r)
            
        pop()
        
    def nearest_point(self, x, y):
        vector = (x - self.x, y - self.y)
        length = math.sqrt(vector[0] * vector[0] + vector[1] * vector[1])
        vector = [component / length for component in vector]
        
        return (self.x + vector[0] * (self.radius), self.y + vector[1] *(self.radius))
        
    def strokecolor(self):
        return (0.3, 0.3, 0.3, 1.0)
    

def join_circles(a, b, width = 5):
    strokewidth(0)
    x1, y1 = a.nearest_point(b.x, b.y)
    x2, y2 = b.nearest_point(a.x, a.y)
    color(c.strokecolor())
    strokewidth(width)
    line(x1, y1, x2, y2)

c = ConcentricCircle(500, 500, 100, 3, 130, 10)
c.draw()

c2 = ConcentricCircle(615, 615, 50, 5, 40, 5)
c2.draw()

c3 = ConcentricCircle(650, 320, 30, 2, 10, 2)
c3.draw()



join_circles(c, c2)
join_circles(c, c3, 2)