How do I make my sprite detect collision?

Question

I'd like the flower image to sense the collision with the basket image. I've tried colliderect and sprite.collide_rect(). the program runs, but it doesn't seem to print("it works") onto the terminal, which I'm assuming is because it doesn't detect the collision.I'd like to know how I can change it so that the fleur object can detect the player.

class Basket(pygame.sprite.Sprite):
       def __init__(self,x,y, name):
            super().__init__()
            self.x=x
            self.y=y
            self.image = pygame.image.load(name).convert_alpha()
            self.rect = self.image.get_rect()

       def render(self):
           main_screen.blit(self.image, (self.x,self.y))

    player = Basket(playerXPosition, playerYPosition, 'basket.png')
    
    class flower(pygame.sprite.Sprite):

        def __init__(self, x, y, img):
            super().__init__()
            self.image = pygame.image.load(img).convert_alpha()
            self.image.set_colorkey(None)
            self.rect = self.image.get_rect()
            self.rect.x = x
            self.rect.y = y 
            self.counter = 0

        def move(self):
            distance = 80
            speed = 2

            if self.counter >= 0 and self.counter <= distance:
                self.rect.y += speed                
            elif self.counter >= distance and self.counter <= distance*2:
                self.rect.y += speed 
            else:
                self.counter = 0 
            
            self.counter += 1 
    
    
    flower_list = pygame.sprite.Group()   
    run = True       
    while run:
        flower_x_position = random.randint(0,1000)
        flowerYposition = random.randint(-600,-300)
        fleur = flower( flower_x_position,flowerYposition, 'sakura.png')
        for event in pygame.event.get():
            flower_list.add(fleur)
            if event.type == pygame.QUIT:
                run = False 
                pygame.quit()
                sys.exit()
        keys = pygame.key.get_pressed()
        if keys[pygame.K_a]:
            player.x -= player_velocity
        if keys[pygame.K_d]:
            player.x += player_velocity
        else:
            print("error")

        for f in flower_list:
            f.move()
            if pygame.sprite.collide_rect(fleur, player):
                print("I work!")       
        main_screen.fill(white)
        main_screen.blit(background_for_main_game, (0,0))
        player.render()
        flower_list.draw(main_screen)
        pygame.display.flip()
        pygame.display.update()  
        clock.tick(40)

Please put the exact error you get into your question. – M-Chen-3 Apr 11 '21 at 02:56 — M-Chen-3, Apr 11 '21 at 02:56

Rabbid76 · Answer 1 · 2021-04-11T15:55:16.480

pygame.Surface.get_rect.get_rect() returns a rectangle with the size of the Surface object, that always starts at (0, 0) since a Surface object has no position.

Basket.rect does not reflect the position of the ball, because the position of the ball is stored in the attributes x and y. For this reason the collision test does not work as intended.
Update player.rect.topleft with (player.x, player.y) before the collision test:

player.rect.topleft = round(player.x), round(player.y)
for f in flower_list:
    f.move()
    if pygame.sprite.collide_rect(fleur, player):
        print("I work!")

How do I make my sprite detect collision?

1 Answers1