mask_fix.py

import sys
import pygame as pg


TRANSPARENT = (0,0,0,0)
BACKGROUND_COLOR = pg.Color("slategray")


class Player(pg.sprite.Sprite):
    def __init__(self,pos,*groups):
        super(Player,self).__init__(*groups)
        self.pos = pos
        self.image = pg.Surface((100,100)).convert_alpha()
        self.image.fill(TRANSPARENT)
        pg.draw.polygon(self.image,(0,255,0),[(50,0),(100,50),(50,100),(0,50)])
        self.rect = self.image.get_rect(center = self.pos)
        self.mask = pg.mask.from_surface(self.image)

    def get_event(self,key):
        if key[pg.K_DOWN]:
            self.rect.y += 1
        if key[pg.K_UP]:
            self.rect.y -= 1
        if key[pg.K_LEFT]:
            self.rect.x -= 1
        if key[pg.K_RIGHT]:
            self.rect.x += 1

    def draw(self,surface):
        self.rect = self.rect.clamp(surface.get_rect())
        surface.blit(self.image,self.rect)


class Enemy(pg.sprite.Sprite):
    def __init__(self,pos,*groups):
        super(Enemy,self).__init__(*groups)
        self.pos = pos
        self.image = pg.Surface((100,100)).convert_alpha()
        self.image.fill(TRANSPARENT)
        pg.draw.circle(self.image,(0,0,255),(50,50),50)
        self.rect = self.image.get_rect(center = self.pos)
        self.mask = pg.mask.from_surface(self.image)
        
    def draw(self, surface):
        surface.blit(self.image, self.rect)


class Game:
    def __init__(self):
        self.screen = pg.display.set_mode((640,480))
        self.player = Player((150,150))
        self.enemies = pg.sprite.Group()
        Enemy((320,240),self.enemies)
        self.done = False
        self.fps = 60.0
        self.clock = pg.time.Clock()

    def event_loop(self):
        key = pg.key.get_pressed()
        self.player.get_event(key)
        for event in pg.event.get():
            if event.type == pg.QUIT:
                self.done = True

    def check_collide(self):
        if pg.sprite.spritecollide(self.player,self.enemies,False,pg.sprite.collide_mask):
            pg.display.set_caption('collide')
        else:
            pg.display.set_caption('do not collide')

    def draw(self):
        self.screen.fill(BACKGROUND_COLOR)
        self.player.draw(self.screen)
        self.enemies.draw(self.screen)

    def run(self):
        while not self.done:
            self.event_loop()
            self.draw()
            self.check_collide()
            pg.display.update()
            self.clock.tick(self.fps)


if __name__ == '__main__':
    pg.init()
    game = Game()
    game.run()
    pg.quit()