敌人pygame奇怪的产卵位置

问题描述

这是我正在开发的部落类型游戏的生存代码。我一直面临一个问题,即外星人(代码中的敌人)有时会在地表底部随机生成,即使我已将它们的生成位置指定为随机(在地表的某个部分内)。>

是什么让它们生成在表面底部,子弹无法触及的地方?

import pygame
import random
import math

# for initialising pygame (req for every pygame app)
pygame.init()

# making the basic window (dimensions must be written inside a tuple )
screen = pygame.display.set_mode((500,500))

# background
background = pygame.image.load('C:/Users/aryan/Downloads/background.jpg')

# load and set the logo
logo = pygame.image.load('C:/Users/aryan/Downloads/bp.png')  # directory of logo
pygame.display.set_icon(logo)
pygame.display.set_caption("space wars")  # program name

# define a variable to control the main loop
running = True

# player
playerimg = pygame.image.load('C:/Users/aryan/Downloads/spaceship.png')
playerX = 218  # x and y coordinates of image
playerY = 350
playerxchange = 0  # this will be the change in movement in x direction of our image
playerychange = 0  # this will be the change in movement in y direction of our image


def player(x,y):
    screen.blit(playerimg,(x,y))  # blit draws our image on the surface(basically the background)
    # Syntax for blit(imagename,(xcoordinate,ycoordinate))


class Enemy:
    def __init__(self):
        self.x = random.randint(0,476)
        self.y = random.randint(0,300)
        self.moveX = 0.2
        self.moveY = 40

    def move(self):
        self.x += self.moveX

        if self.y >= 476:
            self.y = 476
            self.moveY = 0
            self.moveX = 0

        if self.x <= 0:
            self.moveX = 0.1
            self.y += self.moveY
        elif self.x >= 465:
            self.moveX = -0.1
            self.y += self.moveY

    def draw(self):
        screen.blit(enemyimg,(self.x,self.y))


# enemy
enemyimg = pygame.image.load('C:/Users/aryan/Downloads/enemy.png')
enemy_list = []
for i in range(5):
    new_enemy = Enemy()
    enemy_list.append(new_enemy)


# game over
overimg = pygame.image.load('C:/Users/aryan/Downloads/gameover.png')

# bullet
bulletimg = pygame.image.load('C:/Users/aryan/Downloads/bullet.png')
bulletX = 0
bulletY = 350
bulletxchange = 0
bulletychange = 1
bullet_state = "ready"              # "ready" you cant see bullet on screen
                                    # "fire" you can see bullet firing

bullets = []                        # bullets is a list that contains the coordinates of every bullet

score = 0

font30 = pygame.font.SysFont(None,30)


#class



# Functions
def enemy(x,y):
    screen.blit(enemyimg,ycoordinate))


def firebullet(x,y):
    global bullet_state
    bullet_state = "ready"
    bullets.append([x + 12,y + 6]) # Creating a new bullet


def iscollision(enemyX,enemyY,bulletX,bulletY):
    distance = math.sqrt(math.pow(enemyX-bulletX,2)+ math.pow(enemyY-bulletY,2))     # distance formula
    if distance <= 20:
        return True
    else:
        return False

def Textscore(game):
    text2 = font30.render("Your score is: " + str(game),True,(37,97,188))
    screen.blit(text2,(10,45))



# main loop
while running:
    screen.fill((120,120,120))  # in order (r,g,b) . (0,0) is black (255,0) is red...
    screen.blit(background,(0,0))
    # event handling,gets all event from the event queue
    for event in pygame.event.get():
        # only do something if the event is of type QUIT
        if event.type == pygame.QUIT:
            # change the value to False,to exit the main loop
            running = False

        # checking keystroke
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_RIGHT:
                playerxchange += 0.3  # change in movement will be 0.2 towards the right
            if event.key == pygame.K_LEFT:
                playerxchange -= 0.3  # change in movement will be 0.2 towards the right
            if event.key == pygame.K_UP:
                playerychange -= 0.3
            if event.key == pygame.K_DOWN:
               playerychange += 0.3
            if event.key == pygame.K_SPACE:
                bullet_state = "fire"
                firebullet(playerX,playerY)
        if event.type == pygame.KEYUP:
            if event.key == pygame.K_LEFT or event.key == pygame.K_RIGHT or event.key == pygame.K_DOWN or event.key == pygame.K_UP:
                playerxchange = 0
                playerychange = 0

    playerY += playerychange
    playerX += playerxchange  # the value of playerx changes by +- 0.1 depending on keystroke

    if playerX <= -64:  # this teleports the spaceship from left end to right end
        playerX = 564
    elif playerX >= 564:  # this teleports spaceship from right end to left
        playerX = -64

    if playerY >= 436:  # this prevents spaceship from leaving vertically
        playerY = 436
    if playerY <= 0:
        playerY = 0

    # enemy movement
    for enemy in enemy_list:
        enemy.move()

        # bullet movement
    if bullet_state == "fire":
        firebullet(playerX,playerY)


    for bullet in bullets:
        screen.blit(bulletimg,(bullet[0],bullet[1]))  # Print a bullet
        bullet[0] -= bulletxchange  # Updates its position
        bullet[1] -= bulletychange
        if bullet[1] < 0:
            bullets.remove(bullet)

    # collision
    for enemy in enemy_list:
        for bullet in bullets:  # Use a for-loop to iterate through all the bullets in the list.
            collision = iscollision(enemy.x,enemy.y,bullet[0],bullet[1])
            if collision:  # Test if a single bullet collides with the enemy inside the loop.
                score += 1
                print(score)
                bullets.remove(bullet)  # Remove the bullet from the list when it collides with the enemy.
                enemy.x = random.randint(0,476)  # if collision takes place,alien respawns
                enemy.y = random.randint(0,30)



    Textscore(score)
    player(playerX,playerY)  # player method is called AFTER screen.fill otherwise the screen will fill after image has been blitted
    for enemy in enemy_list:  # new edit
        enemy.draw()

    pygame.display.update()  # necessary for events to keep updating

解决方法

问题是您生成的数字超出了 move 类的 Enemy 方法中定义的范围。具体来说,问题在于 x 的上限似乎是 465,但您生成的数字高达 476。

我显然不能测试这个,但替换

enemy.x = random.randint(0,476)  # if collision takes place,alien respawns
enemy.y = random.randint(0,30)

enemy.x = random.randint(1,464)  # if collision takes place,alien respawns
enemy.y = random.randint(1,30)

问题应该会消失。

,

在查看您的代码后,似乎在碰撞后您将重生 y 坐标设置为 0 到 30 之间,我认为这就是您想要的。虽然,生成外星人的原始 y 坐标从 0 到 300;这可能是您的问题,为什么它们会在屏幕下方生成?