EX12.6.py

# 12.6 (Tkinter: two circles intersect?) Using the Circle2D class you defined in Exercise
# 8.18, write a program that enables the user to point the mouse inside a circle
# and drag it. As the circle is being dragged, the label displays whether two circles
# overlap, as shown in Figure 12.18.


import math
from tkinter import *


class Circle2D:
    def __init__(self, x=0, y=0, radius=0):
        self.__x__ = x
        self.__y__ = y
        self.__r__ = radius

    def getX(self):
        return self.__x__

    def getY(self):
        return self.__y__

    def getRadius(self):
        return self.__r__

    def setX(self, x):
        self.__x__ = x

    def setY(self, y):
        self.__y__ = y

    def setRadius(self, radius):
        self.__r__ = radius

    def getArea(self):
        return math.pi * self.getRadius() ** 2

    def getPerimeter(self):
        return math.pi * 2 * self.getRadius()

    def containsPoint(self, x, y):
        dis = math.sqrt((self.getX() - x) ** 2 + (self.getY() - y) ** 2)
        return True if dis <= self.getRadius() else False

    def contains(self, circle):
        dis = math.sqrt((self.getX() - circle.getX()) ** 2 + (self.getY() - circle.getY()) ** 2)
        return True if self.getRadius() >= dis + circle.getRadius() else False

    def overlaps(self, circle):
        dis = math.sqrt((self.getX() - circle.getX()) ** 2 + (self.getY() - circle.getY()) ** 2)
        return True if dis <= self.getRadius() + circle.getRadius() else False

    def __contains__(self, circle):
        return circle.contains(self)

    def __eq__(self, circle):
        return True if self.getRadius() == circle.getRadius() else False

    def __ne__(self, circle):
        return True if self.getRadius() != circle.getRadius() else False

    def __cmp__(self, circle):
        if self.getRadius() > circle.getRadius():
            return 1
        elif self.getRadius() < circle.getRadius():
            return -1
        else:
            return 0

    def __lt__(self, circle):
        return self.getRadius() < circle.getRadius()

    def __gt__(self, circle):
        return self.getRadius() > circle.getRadius()

    def __ge__(self, circle):
        return self.getRadius() >= circle.getRadius()

    def __le__(self, circle):
        return self.getRadius() <= circle.getRadius()


def displayCircle(c, text):
    canvas.delete(text)
    canvas.create_oval(c.getX() - c.getRadius(),
                       c.getY() - c.getRadius(), c.getX() + c.getRadius(), c.getY() + c.getRadius(), tags=text)
    canvas.create_text(c.getX(), c.getY(), text=text, tags=text)


def mouseMoved(event):
    if c1.containsPoint(event.x, event.y):
        c1.setX(event.x)
        c1.setY(event.y)
        displayCircle(c1, "c1")
        if c1.overlaps(c2):
            label["text"] = "Two circles intersect"
        else:
            label["text"] = "Two circles don't intersect"
    if c2.containsPoint(event.x, event.y):
        c2.setX(event.x)
        c2.setY(event.y)
        displayCircle(c2, "c2")
        if c1.overlaps(c2):
            label["text"] = "Two circles intersect"
        else:
            label["text"] = "Two circles don't intersect"


window = Tk()  # Create a window
window.title("Two Circles")  # Set title

width = 300
height = 100
label = Label(window, text="Two circles intersect")
label.pack()
canvas = Canvas(window, width=width, height=height)
canvas.pack()

canvas.bind("<B1-Motion>", mouseMoved)
c1 = Circle2D(10, 10, 30)
c2 = Circle2D(30, 40, 20)
displayCircle(c1, "c1")
displayCircle(c2, "c2")

window.mainloop()