Ping Pong game with python turtle not working

Question

I've been trying to make a python ping pong game using turtle but it does not work. Here is the code, pls help me with it.Whenever I run it, the ball does not go outside 0 and 0. I tried a lot of coordinates for y and x but it does not seem to work. So, if you figured out what the mistake is, please reply back.

import turtle

canavs = turtle.Screen()
canavs.title('Aryesh\'s Ping Pong Game')
canavs.bgcolor('black')
canavs.setup(width=800,height=600)

pa=turtle.Turtle()
pa.penup()
pa.goto(-350,0)
pa.pendown
pa.color('white')
pb=turtle.Turtle()
pb.penup()
pb.goto(350,0)
pb.pendown
pb.color('white')
pb.shape('square')
pb.shapesize(stretch_wid=5,stretch_len=1)

ball=turtle.Turtle()
ball.penup()
ball.goto(0,0)
ball.pendown
ball.color('white')
ball.shape('circle')

speedx=2
speedy=2

def pa_mov_up():
    y=pa.ycor()
    y=y+20
    pa.sety(y)

def pb_mov_up():
    y=pb.ycor()
    y=y+20
    pb.sety(y)

def pa_mov_down():
    y=pa.ycor()
    y=y-20
    pa.sety(y)

def pb_mov_down():
    y=pb.ycor() #get the currenty cor
    y=y-20   #sub -20
    pb.sety(y)  #set that ycor


canavs.listen()
canavs.onkeypress(pa_mov_up,('w'))
canavs.onkeypress(pa_mov_down,('s'))
canavs.onkeypress(pb_mov_up,('Up'))
canavs.onkeypress(pb_mov_down,('Down'))

while True:
    canavs.update()
    ball.setx(ball.xcor()+speedx)
    ball.sety(ball.xcor()+speedy)

    if ball.ycor()>290:
        ball.sety(290)
        speedy*=-1
    elif ball.ycor()>-290:
        ball.sety(-290)
        speedy*=-1

    if ball.xcor()>390:
        ball.goto(0,0)
        speedx=speedx*-1

    elif ball.xcor()<-390:
        ball.goto(0,0)
        speedx=speedx*-1

    if ball.xcor()>340 and ball.ycor()<pb.ycor()+40 and ball.ycor()>pb.ycor()-40:
        ball.setx(340)
        speedx=speedx*-1

    if ball.xcor()<-340 and ball.ycor()<pa.ycor()+40 and ball.ycor()>pb.ycor()-40:
        ball.setx(-340)
        speedx=speedx*-1

turtle.done()

Answer 1

1. According to turtle's document. I didn't find an attribute named pendown . Maybe you mean the pendown() function. The effect of penup() and pendown() is:

   • When it’s up , it means that no line will be drawn when it moves.
   • When it’s down , it means that a line will be drawn when it moves.

2. There are some logical mistakes in your code:

2.1 ball.sety(ball.xcor()+speedy) -> ball.sety(ball.ycor()+speedy)

Original

    ball.setx(ball.xcor()+speedx)
    ball.sety(ball.xcor()+speedy)

2.2 elif ball.ycor()>-290: -> elif ball.ycor()<-290:

Original

    if ball.ycor()>290:
        ball.sety(290)
        speedy*=-1
    elif ball.ycor()>-290:
        ball.sety(-290)
        speedy*=-1

2.3 ball.goto(0,0) -> ball.setx(390) or ball.setx(-390)

Original

    if ball.xcor()>390:
        ball.goto(0,0)
        speedx=speedx*-1

    elif ball.xcor()<-390:
        ball.goto(0,0)
        speedx=speedx*-1

2.4 ball.ycor()<pa.ycor()+40 and ball.ycor()>pb.ycor()-40: to ball.ycor()<pa.ycor()+40 and ball.ycor()>pa.ycor()-40:

Original

    if ball.xcor()<-340 and ball.ycor()<pa.ycor()+40 and ball.ycor()>pb.ycor()-40:
        ball.setx(-340)
        speedx=speedx*-1

The code after modification is

import turtle

canavs = turtle.Screen()
canavs.title('Aryesh\'s Ping Pong Game')
canavs.bgcolor('black')
canavs.setup(width=800,height=600)

pa=turtle.Turtle()
pa.penup()
pa.goto(-350,0)
pa.color('white')
pa.shape('square')
pa.shapesize(stretch_wid=5,stretch_len=1)

pb=turtle.Turtle()
pb.penup()
pb.goto(350,0)
pb.color('white')
pb.shape('square')
pb.shapesize(stretch_wid=5,stretch_len=1)

ball=turtle.Turtle()
ball.penup()
ball.goto(0,0)
ball.pendown()
ball.color('white')
ball.shape('circle')

speedx=2
speedy=2

def pa_mov_up():
    y=pa.ycor()
    y=y+20
    pa.sety(y)

def pb_mov_up():
    y=pb.ycor()
    y=y+20
    pb.sety(y)

def pa_mov_down():
    y=pa.ycor()
    y=y-20
    pa.sety(y)

def pb_mov_down():
    y=pb.ycor() # get the currenty cor
    y=y-20      # sub -20
    pb.sety(y)  # set that ycor


canavs.listen()
canavs.onkeypress(pa_mov_up,('w'))
canavs.onkeypress(pa_mov_down,('s'))
canavs.onkeypress(pb_mov_up,('Up'))
canavs.onkeypress(pb_mov_down,('Down'))

while True:
    canavs.update()
    ball.setx(ball.xcor()+speedx)
    ball.sety(ball.ycor()+speedy)

    if ball.ycor()>290:
        ball.sety(290)
        speedy*=-1
    elif ball.ycor()<-290:
        ball.sety(-290)
        speedy*=-1

    if ball.xcor()>390:
        ball.setx(390)
        speedx=speedx*-1
    elif ball.xcor()<-390:
        ball.setx(-390)
        speedx=speedx*-1

    if ball.xcor()>340 and ball.ycor()<pb.ycor()+40 and ball.ycor()>pb.ycor()-40:
        ball.setx(340)
        speedx=speedx*-1

    if ball.xcor()<-340 and ball.ycor()<pa.ycor()+40 and ball.ycor()>pa.ycor()-40:
        ball.setx(-340)
        speedx=speedx*-1

turtle.done()