check for multiple collisions at sprites in pygame

Question

I am currently working with pygame, and I want to create multiple sprites and check for at least two collisions. I came up with the idea of having two while - loops but it ended up being really complicated. Is there any other way I could try it?

Answer 1

Use pygame.sprite.spritecollide to get a list of the sprites that collide with the player, then loop over this list to do something with the collided sprites.

There's also groupcollide which you can use to detect collisions between two sprite groups. It returns a dictionary with sprites of group 1 as the keys and the collided sprites of group 2 as the values.

import sys
import pygame as pg
from pygame.math import Vector2


class Player(pg.sprite.Sprite):

    def __init__(self, pos, *groups):
        super().__init__(*groups)
        self.image = pg.Surface((120, 60))
        self.image.fill(pg.Color('dodgerblue'))
        self.rect = self.image.get_rect(center=pos)


class Enemy(pg.sprite.Sprite):

    def __init__(self, pos, *groups):
        super().__init__(*groups)
        self.image = pg.Surface((120, 60))
        self.image.fill(pg.Color('sienna1'))
        self.rect = self.image.get_rect(center=pos)


def main():
    screen = pg.display.set_mode((640, 480))
    clock = pg.time.Clock()
    all_sprites = pg.sprite.Group()
    enemy_group = pg.sprite.Group(Enemy((200, 250)), Enemy((350, 250)))
    all_sprites.add(enemy_group)
    player = Player((100, 300), all_sprites)

    done = False

    while not done:
        for event in pg.event.get():
            if event.type == pg.QUIT:
                done = True
            elif event.type == pg.MOUSEMOTION:
                player.rect.center = event.pos

        all_sprites.update()
        # Check which enemies collided with the player.
        # spritecollide returns a list of the collided sprites.
        collided_enemies = pg.sprite.spritecollide(player, enemy_group, False)

        screen.fill((30, 30, 30))
        all_sprites.draw(screen)
        for enemy in collided_enemies:
            # Draw rects around the collided enemies.
            pg.draw.rect(screen, (0, 190, 120), enemy.rect, 4)

        pg.display.flip()
        clock.tick(30)


if __name__ == '__main__':
    pg.init()
    main()
    pg.quit()
    sys.exit()