Pygame 教程 - 坦克碰撞检测

问题描述

我是 Pygame 的新手，正在尝试了解精灵和碰撞检测。我找到了一些代码并尝试为其添加一些功能。

基本思想是我有一个可以原地旋转的多边形。当用户按下空格键时，多边形会发射一个可以在框架周围反弹的射弹。如果弹丸再次击中多边形，我想程序

首先，这是代码

import pygame

class Player(pygame.sprite.Sprite):
    def __init__(self):
        super().__init__()
        self.image = pygame.Surface((32,32))
        self.image.fill((0,0))
        self.image.set_colorkey((0,0))
        self.fire_from = (36,20)
        pygame.draw.polygon(self.image,pygame.Color('dodgerblue'),((0,0),(32,16),(0,32)))
        self.org_image = self.image.copy()
        self.angle = 0
        self.direction = pygame.Vector2(1,0)
        self.rect = self.image.get_rect(center=(200,200))
        self.pos = pygame.Vector2(self.rect.center)

    def update(self,events,dt):

        for e in events:
            if e.type == pygame.KEYDOWN:
                if e.key == pygame.K_SPACE:
                    bullet = Projectile(self.fire_from,self.direction.normalize())
                    self.groups()[0].add(bullet)
        pressed = pygame.key.get_pressed()

        if pressed[pygame.K_LEFT]:
            self.angle += 3
        if pressed[pygame.K_RIGHT]:
            self.angle -= 3

        self.direction = pygame.Vector2(1,0).rotate(-self.angle)
        self.image = pygame.transform.rotate(self.org_image,self.angle)
        self.rect = self.image.get_rect(center=self.rect.center)

class Projectile(pygame.sprite.Sprite):
    def __init__(self,pos,direction):
        super().__init__()
        self.image = pygame.Surface((8,8))
        self.image.fill((0,0))
        pygame.draw.circle(self.image,pygame.Color('orange'),(4,4),4)
        self.rect = self.image.get_rect(center=pos)
        self.direction = direction
        self.pos = pygame.Vector2(self.rect.center)
        self.max_bounce = 10

    def update(self,dt):

        #print(self.pos)
        # Bounding Box of the screen
        screen_r = pygame.display.get_surface().get_rect()

        # where we would move next
        next_pos = self.pos + self.direction * dt

        # we hit a wall
        if not screen_r.contains(self.rect):

            # after 10 hits,destroy self
            self.max_bounce -= 1
            if self.max_bounce == 0:
                return self.kill()

            # horizontal reflection
            if next_pos.x > screen_r.right or next_pos.x < screen_r.left:
                self.direction.x *= -1

            # vertical reflection
            if next_pos.y > screen_r.bottom or next_pos.y < screen_r.top:
                self.direction.y *= -1

            # move after applying reflection
            next_pos = self.pos + self.direction * dt

        # set the new position
        self.pos = next_pos
        self.rect.center = self.pos

def main():
    pygame.init()
    screen = pygame.display.set_mode((500,500))
    tank = Player()
    sprites = pygame.sprite.Group()
    sprites.add(tank)
    #print(tank.groups()[0])
    clock = pygame.time.Clock()
    dt = 0
    running = True
    while running:
        #print(tank.groups()[0])
        events = pygame.event.get()
        for e in events:
            if e.type == pygame.QUIT:
                return
        sprites.update(events,dt)
        screen.fill((30,30,30))
        sprites.draw(screen)
        pygame.display.update()

        ## ALWAYS DETECTS A COLLISION,WHY?
        if len(tank.groups()[0])>1:
            if pygame.sprite.spritecollideany(tank,tank.groups()[0]):
                running = False

        dt = clock.tick(60)

if __name__ == '__main__':
    main()

我在这里收集到 Player 类（即我的坦克）本身有一个精灵组，它在发射时将每个射弹添加到其中。此外，射弹来自多边形的矩形内（因此它最初总是碰撞）

如果弹丸至少弹了 1 次，我只想将它添加到精灵组，这可能吗？或者……有没有更好的方法来做到这一点？

有什么帮助或指点吗？

谢谢 空

解决方法

tank 与自身发生冲突，因为它是 tank.groups()[0] 的成员：

if pygame.sprite.spritecollideany(tank,tank.groups()[0]):

添加一个仅包含项目符号的组：

class Player(pygame.sprite.Sprite):
    def __init__(self):
        # [...]

        self.bullets = pygame.sprite.Group()

    def update(self,events,dt):

        for e in events:
            if e.type == pygame.KEYDOWN:
                if e.key == pygame.K_SPACE:
                    bullet = Projectile(self.fire_from,self.direction.normalize())
                    self.groups()[0].add(bullet)
                    self.bullets.add(bullet)

        # [...]

使用这个Group进行碰撞测试：

def main():
    # [...]

    while running:
        # [...]

        pygame.display.update()

        if pygame.sprite.spritecollideany(tank,tank.bullets):
            running = False

        dt = clock.tick(60)