How to Prevent Ball from Crossing Boundaries in PyGame?-Python Tutorial-php.cn

How to Prevent Ball from Crossing Boundaries in PyGame?

Patricia Arquette

Release： 2024-10-18 21:00:30

Original

371 people have browsed it

How to Prevent Ball from Crossing Boundaries in PyGame?

How to Make a Ball Bounce Off Walls with PyGame

Problem

In PyGame, how do you prevent a ball from going inside a wall when it hits one?

Solution

Nested Loops:

The issue arises from using multiple nested loops. It's more efficient to handle movement within the application loop.

<code class="python">while run:                     
    # Handle movement continuously
    box.y -= box.vel_y        
    box.x += box.vel_x</code>

Copy after login

Boundary Definition:

Define a rectangular region for ball movement using a pygame.Rect object:

<code class="python">bounds = window.get_rect() # full screen
bounds = pygame.Rect(450, 200, 300, 200)  # rectangular region</code>

Copy after login

Boundary Collision Handling:

Update ball direction when it intersects with the boundaries:

<code class="python">if box.x - box.radius < bounds.left or box.x + box.radius > bounds.right:
    box.vel_x *= -1 
if box.y - box.radius < bounds.top or box.y + box.radius > bounds.bottom:
    box.vel_y *= -1</code>

Copy after login

Example

<code class="python">box = Circle(600,300,10)

run = True
start = False
clock = pygame.time.Clock()

while run:                     
    clock.tick(120)  

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False

    keys = pygame.key.get_pressed()
    if keys[pygame.K_SPACE]:
        start = True

    bounds = pygame.Rect(450, 200, 300, 200)
    if start:
        box.y -= box.vel_y        
        box.x += box.vel_x

        if box.x - box.radius < bounds.left or box.x + box.radius > bounds.right:
            box.vel_x *= -1 
        if box.y - box.radius < bounds.top or box.y + box.radius > bounds.bottom:
            box.vel_y *= -1 

    window.fill((0,0,0))
    pygame.draw.rect(window, (255, 0, 0), bounds, 1)
    pygame.draw.circle(window, (44,176,55), (box.x, box.y), box.radius)
    pygame.display.update()</code>

Copy after login

The above is the detailed content of How to Prevent Ball from Crossing Boundaries in PyGame?. For more information, please follow other related articles on the PHP Chinese website!