Python Turtle Space Invaders子弹未击中入侵者

Question

一般来说，我对Turtle和python还是很陌生，所以如果我的代码看起来很乱，我深表歉意。

我目前正在编写太空入侵者的乌龟版，但我不知道为什么我的入侵者撞上乌龟时不会死。该代码似乎与我可以找到的所有其他太空入侵者乌龟程序相同。任何帮助将不胜感激。

import turtle
import random
import math

#### Player ####
player1 = turtle.Turtle()
player1.shape("arrow")
player1.color("white")
player1.speed(0)
player1.penup()
player1.setheading(90)
player1.setposition(0, -175)
player1.speed(4)


def move_right():
    x = player1.xcor()
    x += playerspeed
    if x > 210:
        x = 210
    player1.setx(x)


def move_left():
    x = player1.xcor()
    x -= playerspeed
    if x < -210:
        x = -210
    player1.setx(x)


bulletlist = []


def fire():
    if len(bulletlist) < 5:
        bulletlist.append(Bullet())


#### Window ####
win = turtle.Screen()
win.bgcolor("black")
win.tracer(2)

border_pen = turtle.Turtle()
border_pen.speed(0)
border_pen.color("white")
border_pen.penup()
border_pen.setposition(-225, -225)
border_pen.pensize(3)
border_pen.pendown()
for side in range(4):
    border_pen.fd(450)
    border_pen.lt(90)
border_pen.hideturtle()


### Invader ###
class Invader(turtle.Turtle):
    def __init__(self, xcor, ycor):
        turtle.Turtle.__init__(self)
        self.color("red")
        self.shape("turtle")
        self.penup()
        self.speed(0)
        self.setposition(xcor, ycor)
        self.setheading(270)
        self.speed(1)
        self.hit = 0


### Bullet ###
bulletstate = 1


class Bullet(turtle.Turtle):
    def __init__(self):
        turtle.Turtle.__init__(self)
        self.color("yellow")
        self.shape("arrow")
        self.shapesize(.5, 1)
        self.penup()
        self.speed(0)
        self.setheading(90)
        self.hideturtle()
        self.bulletspeed = 20


fire()


def bullet_movement():
    global firedb
    firedb = bulletlist[-1]
    firedb.speed(0)
    ybul = firedb.ycor()
    ybul += 10
    firedb.sety(ybul)
    if ybul > 195:
        firedb.hideturtle()


def fire_bullet():
    print("fire!")
    firedb = bulletlist[-1]
    firedb.hideturtle()
    x = player1.xcor()
    y = player1.ycor() + 20
    firedb.setpos(x, y)
    firedb.showturtle()
    if firedb.ycor() > 200:
        firedb.hideturtle()
        bulletlist.remove(firedb)


def bulletmake():
    bulletfire = Bullet()


def bulletmechanics():
    fire()
    fire_bullet()


win.listen()
win.onkey(move_left, "Left")
win.onkey(move_right, "Right")
win.onkey(fire_bullet, "space")

enemies = []
xx = -175
xxxx = -175
for invader in range(19):
    if invader <= 9:
        enemies.append(Invader(xx, 200))
        xx += 30
    if invader >= 9:
        enemies.append(Invader(xxxx, 175))
        xxxx += 30

playerspeed = 7
enemyspeed = 8

def isCollision(t1, t2):
    distance = math.sqrt(math.pow(t1.xcor()-t2.xcor(),2)+math.pow(t1.ycor()-t2.ycor(),2))
    if distance < 15:
        return True
    else:
        return False

dead = []
while True:
    global firedb
    firedb = bulletlist[-1]
    fire()
    bullet_movement()
    for Invader in enemies:
        bullet_movement()

        # if Invader.distance(firedb.xcor()+200, firedb.ycor()+200) < 1:
        if isCollision(bulletlist[-1], Invader) == True:
            print("AAAAAAAAGH")
            isCollision(firedb, Invader)
            Invader.hit += 1
        if Invader.hit == 1:
            Invader.color("orange")
        if Invader.hit == 2:
            Invader.color("yellow")
        if Invader.hit == 3:
            Invader.speed(0)
            Invader.setpos(1000, 1000)
            dead.append(Invader)
            Invader.hideturtle()
        for invader in enemies:
            bullet_movement()
            xpos = invader.xcor()
            invader.speed(0)
            xpos += enemyspeed
            invader.setx(xpos)
            if invader.xcor() > 200:
                for invader in enemies:
                    ypos = invader.ycor()
                    ypos -= 40
                    invader.sety(ypos)
                enemyspeed *= -1
            if invader.xcor() < -200:
                for invader in enemies:
                    y = invader.ycor()
                    y -= 40
                    invader.sety(y)
                enemyspeed *= -1

Answer 1

我相信您的问题是您将子弹运动与入侵者运动交织在一起的方式。在您的while True:循环中（在像乌龟这样的事件驱动的世界中不应存在），请在顶层调用bullet_movement()，然后在for循环中，再在嵌套的{ {1}}循环。因此，您看到子弹的位置以及它与入侵者的相对位置不一定相同。

我对您的代码进行了重新设计，出于示例目的，在某些地方对其进行了简化。除了上述问题外，我还修改了代码，以使用乌龟 tilt ，这对于此类海龟面向一个方向但向另一个方向移动的游戏非常适合。而且我已经完全废弃了for函数，因为海龟已经知道如何计算与另一只海龟的距离。

isCollision()

最后，要小心使用Python from turtle import Screen, Turtle class Invader(Turtle): def __init__(self, xcor, ycor): super().__init__(shape="turtle") self.color("red") self.penup() self.setposition(xcor, ycor) self.tilt(-90) self.speed('slow') self.hit = 0 class Bullet(Turtle): def __init__(self): super().__init__(shape="arrow", visible=False) self.shapesize(.5, 1) self.color("yellow") self.penup() self.setheading(90) self.speed('fastest') self.bulletspeed = 20 def move_right(): if player.xcor() + playerspeed < 210: player.forward(playerspeed) def move_left(): if player.xcor() - playerspeed > -210: player.backward(playerspeed) def bullet_movement(): firedb.forward(10) if firedb.ycor() > 195: firedb.hideturtle() def fire_bullet(): if not firedb.isvisible(): x, y = player.position() firedb.setposition(x, y + 20) firedb.showturtle() def isCollision(t1, t2): return t1.distance(t2) < 20 def move(): global enemyspeed if firedb.isvisible(): bullet_movement() for invader in enemies: if firedb.isvisible() and isCollision(firedb, invader): invader.hit += 1 if invader.hit == 1: invader.color("orange") elif invader.hit == 2: invader.color("yellow") elif invader.hit == 3: invader.hideturtle() enemies.remove(invader) firedb.hideturtle() # only one hit per bullet! invader.forward(enemyspeed) if invader.xcor() < -200 or invader.xcor() > 200: for invader in enemies: y = invader.ycor() - 40 invader.sety(y) enemyspeed *= -1 win.update() win.ontimer(move, 50) #### Player #### player = Turtle("arrow") player.color("white") player.penup() player.tilt(90) player.sety(-175) player.speed('fast') #### Window #### win = Screen() win.bgcolor("black") win.tracer(False) border_pen = Turtle(visible=False) border_pen.speed('fastest') border_pen.color("white") border_pen.pensize(3) border_pen.penup() border_pen.setposition(-225, -225) border_pen.pendown() for _ in range(4): border_pen.forward(450) border_pen.left(90) ### Bullet ### firedb = Bullet() enemies = [] xx = -175 xxxx = -190 for invader_count in range(19): if invader_count < 9: enemies.append(Invader(xx, 200)) xx += 30 else: enemies.append(Invader(xxxx, 175)) xxxx += 30 playerspeed = 7 enemyspeed = 2 win.onkey(move_left, "Left") win.onkey(move_right, "Right") win.onkey(fire_bullet, "space") win.listen() move() win.mainloop() 和乌龟global，它们经常被误解。