1

Simple pong: but on the 5th hit the ball goes into the corner and bounces the wrong way vertically off the player1 rectangle, and then it goes to the opponent AI in the corner, also bounces the wrong way vertically off the AI rectangle, and then keeps cycling. How can I fix this? I'm very new to python and pygame so maybe there's something obvious I missed. I made the AI speed faster on purpose.

import pygame, sys, random

pygame.init()

WIDTH = 1100
HEIGHT = 800

screen = pygame.display.set_mode((WIDTH, HEIGHT))

opponent = pygame.Rect(10, HEIGHT/2 - 50, 10, 100)
player = pygame.Rect(WIDTH - 20, HEIGHT/2 - 50, 10, 100)

ball = pygame.Rect(WIDTH/2 - 15 , HEIGHT/2 - 15,30,30)

clock = pygame.time.Clock()

player_speed = 0
opponent_speed = 15

ball_speed_x = 5
ball_speed_y = 5

score_player = 0
score_ai = 0
score = (score_ai, score_player)

while True:


    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            sys.exit()
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_UP:
                player_speed -= 9
            if event.key == pygame.K_DOWN:
                player_speed += 9
        if event.type == pygame.KEYUP:
            if event.key == pygame.K_UP:
                player_speed += 9
            if event.key == pygame.K_DOWN:
                player_speed -= 9



#ball movement

    ball.x += ball_speed_x
    ball.y += ball_speed_y
    # ball colliding with ceiling/floor
    if ball.top <= 0:
        ball_speed_y *= -1

    if ball.bottom >= HEIGHT:
        ball_speed_y *= -1

    # if player misses ball
    if ball.left <= 0:
        ball = pygame.Rect(WIDTH/2 - 15 , HEIGHT/2 - 15,30,30)
        ball_speed_x = 5
        ball_speed_y = 5
        score_player += 1
        pygame.time.delay(1000)
        continue

    if ball.right >= WIDTH:
        ball = pygame.Rect(WIDTH / 2 - 15, HEIGHT / 2 - 15, 30, 30)
        ball_speed_x = 5
        ball_speed_y = 5
        score_ai += 1
        pygame.time.delay(1000)
        continue







    # hitting the ball

    if ball.colliderect(opponent):
        ball_speed_x = -10
        ball_speed_x *= -1
        ball_speed_y = -9
        ball_speed_y *= -1
    if ball.colliderect(player):
        ball_speed_x = 10
        ball_speed_x *= -1
        ball_speed_y = 9
        ball_speed_y *= -1





    # AI for opponent, if ball is higher, go up, if ball is lower, go down
    if ball.y <= opponent.centery:
        opponent.y -= opponent_speed
    if ball.y >= opponent.centery:
        opponent.y += opponent_speed



    # don't let the slides go too high
    player.y += player_speed
    if player.top <= 0:
        player.top = 0
    if player.bottom >= HEIGHT:
        player.bottom = HEIGHT
    if opponent.top <= 0:
        opponent.top = 0
    if opponent.bottom >= HEIGHT:
        opponent.bottom = HEIGHT

    screen.fill((0,0,0))
    pygame.draw.rect(screen, (0, 255, 0), player)
    pygame.draw.rect(screen, (255, 0, 0), opponent)
    pygame.draw.ellipse(screen, (255, 255, 255), ball)
    pygame.draw.aaline(screen, (0,0,255), (WIDTH/2, 0), (WIDTH/2, HEIGHT))

    pygame.display.update()
    clock.tick(60)
Tyrone Steele
  • 13
  • 2
  • 1
    Welcome to Stack Overflow. This is where a good debugger is really valuable. You should get such a tool if you don't have one (PyCharm, VS Code, etc.) and then run your code in that visual debugger. Find a way to have the debugger stop when the ball is approaching or first hits the player. Then step through line by line and look at the code and the values of variables. You're looking for a point where you think one thing should happen but something else happens. Debugging is a HUGE part of programming. You need to get comfortable with being able to watch your code run line by line. – CryptoFool Mar 06 '22 at 17:49
  • Try changing the ball physics variables to identify which ones are dominating in causing this issue. I suspect there's one where you change direction and another condition almost immediately counters this change and the programme loops between these 2 conditions. Alternatively you could force the ball into the corner and see what happens – Kaleba KB Keitshokile Mar 06 '22 at 17:59

1 Answers1

0

See Sometimes the ball doesn't bounce off the paddle in pong game. When the ball hits the player, you need to reverse the velocity along the x-axis and limit the position of the ball ball through the paddle:

while True:
    # [...]

   if ball.colliderect(opponent):
        ball.left = opponent.right
        ball_speed_x *= -1
    if ball.colliderect(player):
        ball.right = player.left
        ball_speed_x *= -1
Rabbid76
  • 202,892
  • 27
  • 131
  • 174