python - Collision not working for pygame Sprites -

i'm trying make spaceship game python programming class, , want use sprite.spritecollideany check if player sprite spaceship colliding of asteroid sprites in spritegroup group, no matter do, doesn't seem work.

here's code:

import pygame import random pygame.init() screen = pygame.display.set_mode((600, 600)) pygame.display.set_caption("asteroids , spaceships")  background = pygame.image.load("background.png") background = background.convert()  white = 255,255,255  #first make asteroids class. class asteroids(pygame.sprite.sprite):     def __init__(self, x, y):         pygame.sprite.sprite.__init__(self)         self.x = x         self.y = y         self.width = 30         self.height = 30          self.i1 = pygame.image.load("smallasteroid.png")         self.i1 = self.i1.convert()         self.i1.set_colorkey(white)         self.rect = self.i1.get_rect()         self.rect.left = x         self.rect.top = y          self.i2 = pygame.image.load("smallasteroid2.png")         self.i2 = self.i2.convert()         self.i2.set_colorkey(white)         self.rect = self.i2.get_rect()         self.rect.left = x         self.rect.top = y          self.i3 = pygame.image.load("mediumasteroid.png")         self.i3 = self.i3.convert()         self.i3.set_colorkey(white)         self.rect = self.i3.get_rect()         self.rect.left = x         self.rect.top = y          self.current = 0      def render(self, image_num):         if image_num == 1:             self.current = 1         if image_num == 2:             self.current = 2         if image_num == 3:             self.current = 3      def update(self):         if self.current == 1:             screen.blit(self.i1, (self.x,self.y))             self.y += random.randint(7,11)             if self.y > screen.get_height():                 self.y = 0          if self.current == 2:             screen.blit(self.i2, (self.x,self.y))             self.y += random.randint(5,9)             if self.y > screen.get_height():                 self.y = 0          if self.current == 3:             screen.blit(self.i3, (self.x,self.y))             self.y += random.randint(3,6)             if self.y > screen.get_height():                 self.y = 0  #and class spaceship    class spaceship(pygame.sprite.sprite):     def __init__(self, x, y):         pygame.sprite.sprite.__init__(self)         self.x = x         self.y = y         self.width = 40         self.height = 60         self.image = pygame.image.load("spaceship.png")         self.image = self.image.convert()         self.image.set_colorkey(white)         self.rect = self.image.get_rect()         self.rect.left = x         self.rect.top = y      def update(self):         screen.blit(self.image,(self.x,self.y))         if self.y > screen.get_height():             self.y = 0         if self.y < screen.get_height()-610:             self.y = screen.get_height()         if self.x > screen.get_width():             self.x = 0         if self.x < screen.get_width()-610:             self.x = screen.get_width()  #main have game run def main():     x_ship, y_ship = 0,0     player = spaceship(300,550)      spritegroup = pygame.sprite.group() #my asteroid sprites grouped here      in range(25):         image_num = random.randint(0,3)         asteroid = asteroids(random.randint(0,500),random.randint(0, 200))         asteroid.render(image_num)         spritegroup.add(asteroid)      clock = pygame.time.clock()     keepgoing = true       while keepgoing:         #this tried use check collisions. know it's not working don't know why.         if pygame.sprite.spritecollideany(player,spritegroup):             #the program quits on collision.             pygame.quit()         event in pygame.event.get():             if (event.type == pygame.quit):                 keepgoing = false             elif event.type == pygame.keyup:                 if event.key == pygame.k_escape:                     keepgoing = false              if (event.type == pygame.keydown):                 if (event.key == pygame.k_left):                     x_ship = -4                 if (event.key == pygame.k_right):                     x_ship = 4                 if (event.key == pygame.k_up):                     y_ship = -4                 if (event.key == pygame.k_down):                     y_ship = 4              if (event.type==pygame.keyup):                 if (event.key==pygame.k_left):                     x_ship = 0                 if (event.key==pygame.k_right):                     x_ship = 0                  if (event.key==pygame.k_up):                     y_ship = 0                 if (event.key==pygame.k_down):                     y_ship = 0          player.x += x_ship         player.y += y_ship         screen.blit(background, (0,0))         spritegroup.clear(screen, background)         player.update()         spritegroup.update()         clock.tick(50)         pygame.display.flip()      pygame.quit()  main() 

i can't figure out why collision isn't working.

your problem neither spaceship nor asteroids classes revise own rects (their hitboxes) on update, , x , y attributes have no direct or automatic connection location of rect. if add self.rect.topleft = self.x, self.y end of update function both classes, respective rects-- is, hitboxes-- move ought be, instead of remaining @ initialized locations, in case (300,550) player and... semi-random offset each asteroid (i'm not sure where, exactly; did make sloppy reproduction of code, test bunch of hunches. apologize not finding exact origin of problem...)

in case, short answer that, although have running check x , y locations of each sprite, haven't told pygame apply location hitbox, , sprite.spritecollideany falsey because hitbox rects were never touching.

putting self.rect.topleft = self.x, self.y @ end of each of sprite class' update functions fix it. (make sure line @ end of function , @ lowest indentation level within def update(self)!)

edit

alternatively, instead of adding aforementioned code update, replace player.x = x_ship , player.y = y_ship in main loop like:

while keepgoing:    ...     player.rect.move_ip(x_ship, y_ship)  # move ship's rect     player.x, player.y = player.rect.topleft  # update it's x , y, if use these elsewhere      item in spritegroup: # update rects asteroid objects         item.rect.topleft = item.x, item.y 

i use update-altering solution, since there's chance solution cause grief when player approaches edges of play field. still, avenue consider.

as suggestion, redefine <sprite>.x , <sprite>.y propertys return self.rect.left , return self.rect.top, respectively, x , y values pinned topleft of hitbox. setter, too, even.

i'm not sure how may wish use parameters in future; it's possible eliminate them entirely, if like, , use rects' locators instead. food thought!

a note:

i'm assuming of sprite's x , y attributes refer top left point of rect box. if point supposed somewhere else (the center, instance), may need make adjustments code, if decide use it.