我如何在這個 python 3.0 游戲中添加生命

Question

我對 python 很陌生，只是想學習它。 我遵循了有關如何制作此游戲的教程並添加了我自己的東西，但我似乎無法添加生命。 我已經嘗試了所有我知道的（不是很多）。 無論如何，我看過的所有教程也沒有奏效，我已經把頭發拉出來了大約 2 天，所以如果有人能提供幫助，我將不勝感激。

import math
import random

import pygame
from pygame import mixer

# Intialize the pygame
pygame.init( )

# create the screen
screen = pygame.display.set_mode((800, 600))

# Background
background = pygame.image.load('editor.jpg')
opensound = mixer.Sound("ftw.wav")
opensound.play( )

# Sound
mixer.music.load("bg noise.wav")
mixer.music.play(-1)

# Caption and Icon
pygame.display.set_caption("Virus Invader")
icon = pygame.image.load('virus.png')
pygame.display.set_icon(icon)

# Player
playerImg = pygame.image.load('people.png')
playerX = 370
playerY = 480
playerX_change = 0

# Enemy
enemyImg = []
enemyX = []
enemyY = []
enemyX_change = []
enemyY_change = []
num_of_enemies = 6

for i in range(num_of_enemies):
    enemyImg.append(pygame.image.load('virus.png'))
    enemyX.append(random.randint(0, 736))
    enemyY.append(random.randint(50, 150))
    enemyX_change.append(1)
    enemyY_change.append(40)

# Bullet

# Ready - You can't see the bullet on the screen
# Fire - The bullet is currently moving

bulletImg = pygame.image.load('ligature.png')
bulletX = 0
bulletY = 480
bulletX_change = 0
bulletY_change = 2
bullet_state = "ready"

# Score

score_value = 0
font = pygame.font.Font('freesansbold.ttf', 32)

textX = 10
testY = 10

# Game Over
over_font = pygame.font.Font('freesansbold.ttf', 64)

def Game_start_text():
    over_text = over_font.render("Let the games begin!", True, (64, 64, 64))
    screen.blit(over_text, (200, 250))


def show_score(x, y):
    score = font.render("Score : " + str(score_value), True, (255, 255, 255))
    screen.blit(score, (x, y))


def game_over_text():
    over_text = over_font.render("GAME OVER", True, (255, 255, 255))
    screen.blit(over_text, (200, 250))


def player(x, y):
    screen.blit(playerImg, (x, y))


def enemy(x, y, i):
    screen.blit(enemyImg[i], (x, y))


def fire_bullet(x, y):
    global bullet_state
    bullet_state = "fire"
    screen.blit(bulletImg, (x + 16, y + 10))


def isCollision(enemyX, enemyY, bulletX, bulletY):
    distance = math.sqrt(math.pow(enemyX - bulletX, 2) + (math.pow(enemyY - bulletY, 2)))
    if distance < 27:
        return True
    else:
        return False


# Game Loop
running = True
while running:

    # RGB = Red, Green, Blue
    screen.fill((0, 0, 0))
    # Background Image
    screen.blit(background, (0, 0))
    for event in pygame.event.get( ):
        if event.type == pygame.QUIT:
            running = False

        # if keystroke is pressed check if its right or left
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT:
                playerX_change = -2
            if event.key == pygame.K_RIGHT:
                playerX_change = 2
            if event.key == pygame.K_SPACE:
                if bullet_state is "ready":
                    bulletSound = mixer.Sound("stab.wav")
                    bulletSound.play( )
                    # Get the current x cordinate of the charctar
                    bulletX = playerX
                    fire_bullet(bulletX, bulletY)

        if event.type == pygame.KEYUP:
            if event.key == pygame.K_LEFT or event.key == pygame.K_RIGHT:
                playerX_change = 0

    # 5 = 5 + -0.1 -> 5 = 5 - 0.1
    # 5 = 5 + 0.1

    playerX += playerX_change
    if playerX <= 0:
        playerX = 0
    elif playerX >= 736:
        playerX = 736

    # Enemy Movement
    for i in range(num_of_enemies):

        # Game Over
        if enemyY[i] > 440:
            for j in range(num_of_enemies):
                enemyY[j] = 2000
            game_over_text( )
            break

        enemyX[i] += enemyX_change[i]
        if enemyX[i] <= 0:
            enemyX_change[i] = 1
            enemyY[i] += enemyY_change[i]
        elif enemyX[i] >= 736:
            enemyX_change[i] = -1
            enemyY[i] += enemyY_change[i]

        # Collision
        collision = isCollision(enemyX[i], enemyY[i], bulletX, bulletY)
        if collision:
            explosionSound = mixer.Sound("street fighter die.wav")
            explosionSound.play( )
            bulletY = 480
            bullet_state = "ready"
            score_value += 1
            enemyX[i] = random.randint(0, 736)
            enemyY[i] = random.randint(50, 150)

        enemy(enemyX[i], enemyY[i], i)

    # Bullet Movement
    if bulletY <= 0:
        bulletY = 480
        bullet_state = "ready"

    if bullet_state is "fire":
        fire_bullet(bulletX, bulletY)
        bulletY -= bulletY_change

    player(playerX, playerY)
    show_score(textX, testY)
    pygame.display.update( )

Answer 1

將它添加到您的代碼中之所以如此困難，是因為有一大堆額外的代碼在路上。

發生這種情況時，請退后一步，嘗試編寫一個框架來滿足您的需要。 當在一個龐大的系統上工作時，比如追蹤一個復雜的錯誤，通常你會注釋掉代碼的一部分，以將問題空間與可管理的東西配對。 你的代碼很小，所以也許你可以忽略很多。

無論如何，備份您的代碼，然后開始一點一點地添加更改，像您一樣測試 go。

首先添加一個生命計數器：

# Player
playerLives    = 3                                 # <<-- HERE
playerImg      = pygame.image.load('people.png')
playerX        = 370
playerY        = 480
playerX_change = 0

然后是一些測試生命損失的方法：

    # if keystroke is pressed check if its right or left
    elif event.type == pygame.KEYDOWN:
        if event.key == pygame.K_LEFT:
            playerX_change = -2
        elif event.key == pygame.K_RIGHT:
            playerX_change = 2
        elif event.key == pygame.K_d:   # TEST CODE - Die on 'd'  <<-- HERE
            print( "Player Dies" )
            playerLives -= 1

現在測試這個？ 當您按 d 時，它是否打印“玩家死亡”？

那么......當生命為零時應該發生什么？ 也許玩家不能再移動了：

# Has the player run out of lives?
if ( playerLives <= 0 ):
    game_over_text()
else:
    # Player still alive, allow controls, draw player
    playerX += playerX_change
    if playerX <= 0:
        playerX = 0
    elif playerX >= 736:
        playerX = 736
    player(playerX, playerY)

添加這些下一個更改，測試它們。 是否每次按d三次打印“玩家死亡”，並導致調用game_over_text() function？

然后更改show_score() function 以同樣繪制左邊的生命：

def show_score(x, y):
    score = font.render("Score : " + str(score_value), True, (255, 255, 255))
    screen.blit(score, (x, y))
    # Write the Lives-left to the right of the score
    lives = font.render("Lives : " + str(playerLives), True, (255, 255, 255))
    screen.blit(lives, (x+200, y))

測試一下。 屏幕上的分數是否有效？ 不？ 做一些小改動，再次測試，不斷調整，不斷修復。 如果這一切都變成了手推車中的地獄，您只需要進行小的更改即可撤消它。

現在失去生命的機制正在工作，找到它實際上應該奪走生命的地方，並添加以下更改：

    # Game Over
    if enemyY[i] > 440:
        for j in range(num_of_enemies):
            enemyY[j] = 2000
        playerLives -= 1           # <<-- lose a life
        #game_over_text( )
        reset_enemy_positions()    # <<-- move enemies back to top, TODO!
        break

當然，如果您將敵人留在 440 行以下，則喪命情況仍然成立。 因此，每幀更新，玩家將繼續每秒失去許多生命。 敵人需要回到起始位置（或類似的位置）。

無論如何，我希望這能給你一個正確的方向。 也許它會幫助您嘗試從頭開始自己編寫一些東西。 即使只是打開 window。 然后添加密鑰處理。 然后畫一些東西......逐漸增加你的知識，我認為你會這樣學得更快。 每本編程書籍都以“Hello World”開頭是有原因的。