why collision between two moving objects on pygame dont work?

问题

I am doing a snake game(there is two snakes on the game) with pygame and i want to detect when the snake head collides with the another snake body, do that for both and a special case when the both heads collides, im doing currently the collision between the snake head and the other snake body, it works fine if one of the snakes is frozen and the other is moving, but if both is moving the collision just dont work heres the code that moves the snakes:

new_pos = None
        if direction == 'DOWN':
            new_pos = (snake[0][0], snake[0][1] + size)
        if direction == 'UP':
            new_pos = (snake[0][0], snake[0][1] - size)
        if direction == 'LEFT':
            new_pos = (snake[0][0] - size, snake[0][1])
        if direction == 'RIGHT':
            new_pos = (snake[0][0] + size, snake[0][1])
        if new_pos:
            snake = [new_pos] + snake
            del snake[-1]

keep in mind that the code that movements the other snake is the same but snake turns into snake2, new_pos into new_pos2, etc

collision code:

if snake2[0] in snake[1:]:
            gameOverBlue()

if snake2[0] in snake[1:]:
            gameOverRed()

edit: i figured I should put the code that makes the snake too:

#snake
    size = 15
    s_pos = 60
    snake = [(s_pos + size * 2, s_pos),(s_pos + size, s_pos),(s_pos, s_pos)]
    s_skin = pygame.Surface((size, size))
    s_skin.fill((82,128,208))
#snake2
    size2 = 15
    s2_pos = 195
    snake2 = [(s2_pos + size2 * 2, s2_pos),(s2_pos + size2, s2_pos),(s2_pos, s2_pos)]
    s2_skin = pygame.Surface((size2, size2))
    s2_skin.fill((208,128,82))

回答1:

You need to evaluate whether the head of snake is in the list snake2, including the head of snake2:

if snake[0] in snake2:
    gameOverBlue()

and if the head of snake2 is in snake:

if snake2[0] in snake:
    gameOverRed()

If you want to detect if the heads of the snakes are colliding the you have to compare snake[0] and snake2[0] separately:

if snake[0] == snake2[0]:
    print("heads are colliding")

if snake[0] in snake2[1:]:
    gameOverBlue()
if snake2[0] in snake[1:]:
    gameOverRed()

来源：https://stackoverflow.com/questions/64539458/why-collision-between-two-moving-objects-on-pygame-dont-work

标签

python

pygame

collision-detection

collision