Pygame spritecollide not removing sprites

Question

Please help.

I am new to pygame. I can't work out why my collision detection isn't working. I am using spritecollide and just cannot see why sprites aren't being removed from sprites_list. I am using an image and a circle drawn by pygame could this have something to do with it?

The game should be a very simple collection game where the player sprite can move around using arrow keys and cause the red circles to disappear. Many thanksin advance for any help with this.

import pygame, sys
from pygame.locals import *
import random


class Player(pygame.sprite.Sprite):
    def __init__(self):
        pygame.sprite.Sprite.__init__(self)
        self.image = pygame.image.load("king_black.png")
        self.rect = self.image.get_rect()

class CircleSprite(pygame.sprite.Sprite):
    def __init__(self, colour, width, height):
        pygame.sprite.Sprite.__init__(self)
        self.image = pygame.Surface([width, height])
        self.rect = self.image.get_rect()
        self.image.set_colorkey((0,0,0))
        pygame.draw.ellipse(self.image, colour, [0, 0, width, height])


#initialise pygame
pygame.init()

#Setup game clock
FPS = 30 #Frames per second
clock = pygame.time.Clock()

#Setup display
DISPLAYSURF = pygame.display.set_mode((400, 300))
pygame.display.set_caption("Hello world!")

#Setup colours
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)
RED = (255, 0, 0)

rect_x = 200
rect_y = 150
rect_width = 100
rect_height = 50

player = Player()

#Create a sprite group
sprites_list = pygame.sprite.Group()

#Circle list
circle_list = pygame.sprite.Group()

for i in range(10):
    circle = CircleSprite(RED, 40, 40)

    # Set a random location for the circle
    circle.rect.x = random.randrange(400)
    circle.rect.y = random.randrange(300)

    # Add the circle to the list of objects
    sprites_list.add(circle)

sprites_list.add(player)

#Main game loop
while True:

  for event in pygame.event.get():
    if event.type == QUIT:
      pygame.quit()
      sys.exit()

  #Looks for pressed keys
  keys_pressed = pygame.key.get_pressed()

  #Responds to most recent key pressed
  if keys_pressed[K_LEFT]:
    rect_x -= 5
  if keys_pressed[K_RIGHT]:
    rect_x += 5
  if keys_pressed[K_UP]:
    rect_y -= 5
  if keys_pressed[K_DOWN]:
    rect_y += 5

  #Collision detection
  sprite_hits = pygame.sprite.spritecollide(player, sprites_list, True)

  #Draw screen background
  DISPLAYSURF.fill((WHITE))

  #Draw circles to display
  sprites_list.draw(DISPLAYSURF)

  #Blit image to display and flip it.
  DISPLAYSURF.blit(player.image, (rect_x, rect_y))
  pygame.display.flip()

  clock.tick(FPS)

skrx skrx · Accepted Answer · 2018-01-11T14:20:49

If you print the player's rect or blit the image at the rect (DISPLAYSURF.blit(player.image, player.rect)), you'll see that it never moves and just stays at the default coordinates (0, 0). Since the rect is used for the collision detection, the player is unable to collide with the circle sprites.

You have to update the position of the rect as well every frame or increment the player.rect.x and player.rect.y directly.

if keys_pressed[K_LEFT]:
    rect_x -= 5
if keys_pressed[K_RIGHT]:
    rect_x += 5
if keys_pressed[K_UP]:
    rect_y -= 5
if keys_pressed[K_DOWN]:
    rect_y += 5
player.rect.topleft = (rect_x, rect_y)

Pygame spritecollide not removing sprites

1 Answers