Question

Modify the provided code to do the following:

1) Add starting position to the Ball init function
2) Move the wall collision code into a collision function that is called by the update function
3) Add Ball collision code that checks for collisions between ball and ball2 objects. Upon collision, send the balls in a realistic direction.

Be sure to use bounding circles for collision accuracy.

Python tkinter code below:

from tkinter import *
import math

WIDTH=800
HEIGHT=600
tk = Tk()
canvas = Canvas(tk, width=WIDTH, height=HEIGHT, bg="blue")
canvas.pack()

class Ball:
def __init__(self, tag, color, size, vx, vy):
self.shape = canvas.create_oval(0, 0, size, size, fill=color, tags=tag)
self.vx = vx
self.vy = vy

def update(self):
canvas.move(self.shape, self.vx, self.vy)
[x1,y1,x2,y2] = canvas.coords(self.shape)
if x2 >= WIDTH or x1 <= 0:
self.vx *= -1
if y2 >= HEIGHT or y1 <= 0:
self.vy *= -1

def cycle():
canvas.tag_raise("bg")
ball.update()
canvas.tag_raise("ball")
ball2.update()
canvas.tag_raise("ball2")
tk.update_idletasks()
tk.after(3, cycle)

bg = canvas.create_rectangle(0, 0, WIDTH+1, HEIGHT+1, fill="blue", tags="bg")
ball = Ball("ball","black",40,4,4)
ball2 = Ball("ball2","red",20,6,6)
tk.after(0, cycle)
tk.mainloop()

Answer 1

Please find the code below::

from tkinter import *
import math

WIDTH=800
HEIGHT=600
tk = Tk()
canvas = Canvas(tk, width=WIDTH, height=HEIGHT, bg="blue")
canvas.pack()

class Ball:
def __init__(self, tag, color, size, vx, vy,startingX,startingY):
self.shape = canvas.create_oval(startingX, startingY, startingX+size, startingY+size, fill=color, tags=tag)
self.vx = vx
self.radius = size/2
self.vy = vy
  
def update(self):
self.checkWallCollision()
  
def checkWallCollision(self):
canvas.move(self.shape, self.vx, self.vy)
[x1,y1,x2,y2] = canvas.coords(self.shape)
if x2 >= WIDTH or x1 <= 0:
self.vx *= -1
if y2 >= HEIGHT or y1 <= 0:
self.vy *= -1
  
def checkBallCollision(ball1,ball2):
radius1 = ball1.radius
radius2 = ball2.radius
totalRadiusDistance = radius1+radius2
[x1,y1,x2,y2] = canvas.coords(ball1.shape)
centerX1 = x1+radius1
centerY1 = y1+radius1
[xx1,yy1,xx2,yy2] = canvas.coords(ball2.shape)
centerX2 = xx1+radius2
centerY2 = yy1+radius2
centerDistances = math.sqrt( math.pow(centerX1-centerX2, 2) + math.pow(centerY1-centerY2, 2))
if(centerDistances<=totalRadiusDistance):
ball1.vx *= -1
ball1.vy *= -1
ball2.vx *= -1
ball2.vy *= -1
  
  
def cycle():
canvas.tag_raise("bg")
ball.update()
canvas.tag_raise("ball")
ball2.update()
checkBallCollision(ball,ball2)
canvas.tag_raise("ball2")
tk.update_idletasks()
tk.after(3, cycle)

bg = canvas.create_rectangle(0, 0, WIDTH+1, HEIGHT+1, fill="blue", tags="bg")
ball = Ball("ball","black",40,4,4,0,0)
ball2 = Ball("ball2","red",20,6,6,100,0)
tk.after(0, cycle)
tk.mainloop()

output: