Pong.py

# Implementation of classic arcade game Pong

try:
    import simplegui
except ImportError:
    import SimpleGUICS2Pygame.simpleguics2pygame as simplegui

import random

# initialize globals - pos and vel encode vertical info for paddles
WIDTH = 600
HEIGHT = 400       
BALL_RADIUS = 10
PAD_WIDTH = 8
PAD_HEIGHT = 80
HALF_PAD_WIDTH = PAD_WIDTH / 2
HALF_PAD_HEIGHT = PAD_HEIGHT / 2
LEFT = False
RIGHT = True

paddle1_pos=HEIGHT/2.5
paddle2_pos=HEIGHT/2.5
paddle1_vel=0
paddle2_vel=0
paddle_vel=5

ball_pos=[WIDTH/2, HEIGHT/2]
ball_vel=[0,1]

score1=0
score2=0
# initialize ball_pos and ball_vel for new bal in middle of table
# if direction is RIGHT, the ball's velocity is upper right, else upper left
def spawn_ball(direction):
    global ball_pos, ball_vel # these are vectors stored as lists
    ball_pos=[WIDTH/2, HEIGHT/2]
    ball_vel[0]=-(random.randrange(180,320) / 100)
    if direction:
        ball_vel[0]*=-1
    ball_vel[1]= -random.randrange(80, 200) / 100


# define event handlers
def new_game():
    global paddle1_pos, paddle2_pos, paddle1_vel, paddle2_vel  # these are numbers
    global score1, score2  # these are ints
    
    spawn_ball(0)
    

def draw(canvas):
    global score1, score2, paddle1_pos, paddle2_pos, ball_pos, ball_vel
 
        
    # draw mid line and gutters
    canvas.draw_line([WIDTH / 2, 0],[WIDTH / 2, HEIGHT], 1, "White")
    canvas.draw_line([PAD_WIDTH, 0],[PAD_WIDTH, HEIGHT], 1, "White")
    canvas.draw_line([WIDTH - PAD_WIDTH, 0],[WIDTH - PAD_WIDTH, HEIGHT], 1, "White")
        
    # update ball
    ball_pos[0] += ball_vel[0]
    ball_pos[1] += ball_vel[1]
    
    if (ball_pos[0]<= PAD_WIDTH + BALL_RADIUS or ball_pos[0]>= WIDTH-PAD_WIDTH-BALL_RADIUS):
        ball_vel[0]*=-1
    
    
        if ball_pos[0]>WIDTH/2:
            if (ball_pos[1]<paddle2_pos or ball_pos[1]>paddle2_pos+PAD_HEIGHT):
                score1+=1
                spawn_ball(LEFT)
            else:
                ball_vel[0]+= .1 *ball_vel[0]
            
        if ball_pos[0]<WIDTH/2:
            if (ball_pos[1]<paddle1_pos or ball_pos[1]>paddle1_pos+PAD_HEIGHT):
                score2+=1
                spawn_ball(RIGHT)
            else:
                ball_vel[0]+= .1 *ball_vel[0]  
            
    if ball_pos[1] <= BALL_RADIUS or ball_pos[1] >= (HEIGHT - BALL_RADIUS):
        ball_vel[1] *= -1        
            
    # draw ball
    canvas.draw_circle(ball_pos,BALL_RADIUS,2,"White","Green")
    
    # update paddle's vertical position, keep paddle on the screen
    global paddle1_vel, paddle2_vel
    
    if (paddle1_pos <= HEIGHT - PAD_HEIGHT and paddle1_vel > 0) or (paddle1_pos >= 0 and paddle1_vel < 0) :
        paddle1_pos += paddle1_vel    
    elif (paddle2_pos <= HEIGHT - PAD_HEIGHT and paddle2_vel > 0) or (paddle2_pos >= 0 and paddle2_vel < 0) :
        paddle2_pos += paddle2_vel  
        
    
    
    # draw paddles
    canvas.draw_polygon([[0,paddle1_pos],[PAD_WIDTH,paddle1_pos], [PAD_WIDTH,paddle1_pos+PAD_HEIGHT],[0,paddle1_pos+PAD_HEIGHT]],1,"Green","White")
    canvas.draw_polygon([[WIDTH-PAD_WIDTH,paddle2_pos],[WIDTH,paddle2_pos], [WIDTH,paddle2_pos+PAD_HEIGHT],[WIDTH-PAD_WIDTH,paddle2_pos+PAD_HEIGHT]],1,"Green","White")
    
    # determine whether paddle and ball collide    
    
    # draw scores
    canvas.draw_text(str(score1), [225, 80], 60, "pink")    
    canvas.draw_text(str(score2), [350, 80], 60, "pink")
        
def keydown(key):
    global paddle1_vel, paddle2_vel
    
    #Player1
    if key==simplegui.KEY_MAP["w"]:
        paddle1_vel= -paddle_vel
    if key==simplegui.KEY_MAP["s"]:
        paddle1_vel= +paddle_vel
        
    #Player2
    if key==simplegui.KEY_MAP["up"]:
        paddle2_vel= -paddle_vel
    if key==simplegui.KEY_MAP["down"]:
        paddle2_vel= +paddle_vel
    
   
def keyup(key):
    global paddle1_vel, paddle2_vel
    
    #Player1
    if key==simplegui.KEY_MAP["w"]:
        paddle1_vel= 0
    if key==simplegui.KEY_MAP["s"]:
        paddle1_vel= 0
        
    #Player2
    if key==simplegui.KEY_MAP["up"]:
        paddle2_vel= 0
    if key==simplegui.KEY_MAP["down"]:
        paddle2_vel= 0


# create frame
frame = simplegui.create_frame("Pong", WIDTH, HEIGHT)
frame.set_draw_handler(draw)
frame.set_keydown_handler(keydown)
frame.set_keyup_handler(keyup)
frame.add_button("Restart",new_game,200)


# start frame
new_game()
frame.start()