有没有办法在 python 中生成不同的对象实例？

Question

我正在用 python 制作游戏（使用街机库）。我做了一个“武器”类，我可以在其中制作不同的武器实例（具有不同的精灵、伤害统计等）。我想要它，所以当某个变量为真时，枪会创建一个类的新实例（子弹），但我不想将每个实例分配给一个新变量等。有没有办法做到这一点？并且请不要太复杂，因为我在 Python 方面还没有走得太远。class Weapon(object):    def __init__(self, sprite, size):        self.weapon = arcade.Sprite(sprite,size)        self.attacking = True    def draw(self):        self.weapon.draw()        if self.attacking:            # Creates an instance of Bullet Class with initialized variables            # Every single time this variable is turned into True

Answer 1

我不会那样做，我会创建一个包含 draw() 逻辑的 Sprite 类，其中一个 Player 和一个 Weapon 类将继承玩家将包含武器并在包含你所有的 Game 类中实例化逻辑

class Sprite:

    def draw(self):

        # Draw logic, maybe have an image sprite member variable

class Bullet(Sprite):

    def __init__(self, posX, posY, angle, velocity, game):

        self.posX = posX

        self.posY = posY

        self.angle = angle

        self.velocity = velocity

        self.game = game

        self.game.bullets.append(self)

    def fly(self):

         # Add some trigonometry here using the angle and velocity and implement some collision algorithm

class Weapon(Sprite):

    posX = 0

    posY = 0 #Probably gonna need to keep track of the position, you should init them in constructor

    angle = PI

    bullets = []

    def shoot(self):

        if len(self.bullets) <= 10: # maybe you don't want too many bullets

            self.bullets.append(Bullet(self.posX, self.posY, self.angle, 100))

class Player(Sprite):

    posX = 0

    posY = 0

    def __init__(self, game):

        self.game = game

        self.weapon = Weapon()

    def shoot(self):

        self.weapon.shoot()

class Game:

    players = []

    bullets = []

    def __init__(self, player_count=1):

        for i in range(player_count):

            self.players.append(Player(self))

    def draw(self):

        for player in self.players:

            player.draw()

        for bullet in self.bullets:

            bullet.fly()

def main():

    game = Game(1)

    game.start() # need to implement start logic, rerendering every few MS, etc.

if __name__ == "__main__":

    main()

Answer 2

您可以为此使用设置器

class Weapon(object):

    ...

    @property

    def attacking(self):

        return self._attacking

    @attacking.setter

    def attacking(self, value):

        if value and not self._attacking:

            # logic for when attacking become true

        self._attacking = value

然后，当您somewep.attacking = True对代码的其他部分执行操作时，setter 将运行。关于保存 Bullet 实例。如果实例化Bullet具有它需要的所有副作用，那么你不需要保存它，Bullet(parameters, ...)你会没事的。

如果Bullet框架正在绘制，那么它有一个对它的引用，只要框架引用它，GC就不应该收集它