How To Fix Infinite Jump Bug In Pygame?

I am trying to make a game, but you can keep spamming 'w' (jump) for infinite height which is really bad when you are trying to make a platformer game. This is all my code: GRAVITY

Solution 1:

You can define a on_ground variable that you set to True if the player touches the ground. When the user wants to jump (presses 'w') you first check if on_ground: and then change the y_change and set on_ground to False.

import pygame


pygame.init()

gameDisplay = pygame.display.set_mode((800, 600))
clock = pygame.time.Clock()

GRAVITY = .5

player_img = pygame.Surface((30, 50))
player_img.fill((40, 120, 200))
x = 100
y = 500
x_change = 0
y_change = 0
on_ground = False

diedorgameover = Falsewhilenot diedorgameover:
    foreventin pygame.event.get():
        ifevent.type == pygame.QUIT:
            diedorgameover = True
        elif event.type == pygame.KEYDOWN:
            ifevent.key == pygame.K_a:
                x_change = -5
            elif event.key == pygame.K_d:
                x_change = 5
            elif event.key == pygame.K_s:
                y_change = 5
            elif event.key == pygame.K_w:
                # Only jump if the player ison the ground.
                if on_ground:
                    y_change = -12
                    on_ground = False
        elif event.type == pygame.KEYUP:
            ifevent.key == pygame.K_a orevent.key == pygame.K_d:
                x_change = 0

    y_change += GRAVITY
    x += x_change
    y += y_change

    # If the player ison the ground.
    if y >= gameDisplay.get_height() - 68:
        y = gameDisplay.get_height() - 68
        y_change = 0
        on_ground = True

    gameDisplay.fill((30, 30, 30))
    gameDisplay.blit(player_img, (x, y))

    pygame.display.update()
    clock.tick(60)


pygame.quit()

Also delete these lines, otherwise the player can stop while in the air if the key is released:

ifevent.key == pygame.K_s orevent.key == pygame.K_w:
    y_change = 0