Pygame Playlist在后台连续播放

Question

我正在尝试为我的游戏获取背景音乐，但我似乎不能完美地弄清楚。我过去用过pygame，但它只在我的游戏演职员期的一首歌中使用过。我想让播放列表连续播放，随机挑选每首曲目。我已经设法让它在一个单独的测试文件中工作。我将在下面发布这段代码。

问题是，当我在我的主游戏中调用这个函数时，音乐播放第一首曲目，然后停止。如果我输入

while pygame.mixer.music.get_busy():
    continue

它只是播放音乐，不让我玩游戏。我想让它在用户玩游戏时不断循环播放列表(这是一个基于文本的游戏，所以它经常使用raw_input()。

下面是我的代码：

import pygame
import random

pygame.mixer.init()

_songs = [songs, are, here]

_currently_playing_song = None

def music():
    global _currently_playing_song, _songs
    next_song = random.choice(_songs)
    while next_song == _currently_playing_song:
        next_song = random.choice(_songs)
    _currently_playing_song = next_song
    pygame.mixer.music.load(next_song)
    pygame.mixer.music.play()

while True: ## This part works for the test, but will not meet my needs
    music() ## for the full game.
    while pygame.mixer.music.get_busy():
        continue

(附注:我通过Zed Shaw的“以艰难的方式学习python”学习了Python，所以我的游戏结构使用了书中的引擎和地图系统)

Answer 1

您可以使用线程在后台播放音乐。

import threading
musicThread = threading.Thread(target=music)
musicThread.start()

如果你想在不关闭游戏的情况下停止音乐，你应该杀死这个线程。

Answer 2

您可以设置一个在音乐结束时发布到事件队列中的pygame.mixer.music.set_endevent()。然后你只需选择另一首歌。大致是这样的：

import os
import pygame
pygame.init()
pygame.mixer.init()

SIZE = WIDTH, HEIGHT = 720, 460
screen = pygame.display.set_mode(SIZE)

MUSIC_ENDED = pygame.USEREVENT
pygame.mixer.music.set_endevent(MUSIC_ENDED)


BACKGROUND = pygame.Color('black')


class Player:

    def __init__(self, position):
        self.position = pygame.math.Vector2(position)
        self.velocity = pygame.math.Vector2()

        self.image = pygame.Surface((32, 32))
        self.rect =  self.image.get_rect(topleft=self.position)

        self.image.fill(pygame.Color('red'))

    def update(self, dt):
        self.position += self.velocity * dt
        self.rect.topleft = self.position


def load_music(path):
    songs = []
    for filename in os.listdir(path):
        if filename.endswith('.wav'):
            songs.append(os.path.join(path, filename))
    return songs


def run():
    songs = load_music(path='/Users/Me/Music/AwesomeTracks')

    song_index = 0  # The current song to load
    pygame.mixer.music.load(songs[song_index])
    pygame.mixer.music.play()
    song_index += 1

    clock = pygame.time.Clock()
    player = Player(position=(WIDTH / 2, HEIGHT / 2))

    while True:
        dt = clock.tick(30) / 1000

        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                quit()
            elif event.type == pygame.KEYDOWN:
                if event.key == pygame.K_a:
                    player.velocity.x = -200
                elif event.key == pygame.K_d:
                    player.velocity.x = 200
                elif event.key == pygame.K_w:
                    player.velocity.y = -200
                elif event.key == pygame.K_s:
                    player.velocity.y = 200
            elif event.type == pygame.KEYUP:
                if event.key == pygame.K_a or event.key == pygame.K_d:
                    player.velocity.x = 0
                elif event.key == pygame.K_w or event.key == pygame.K_s:
                    player.velocity.y = 0
            elif event.type == MUSIC_ENDED:
                song_index = (song_index + 1) % len(songs)  # Go to the next song (or first if at last).
                pygame.mixer.music.load(songs[song_index])
                pygame.mixer.music.play()

        screen.fill(BACKGROUND)

        player.update(dt)
        screen.blit(player.image, player.rect)

        pygame.display.update()

run()

所以实际的解决方案只有3个部分

对于event queue for event in pygame.event.get(): if event.type == MUSIC_ENDED:中的事件，当一首歌曲完成pygame.mixer.music.set_endevent(MUSIC_ENDED)

• Check时，

1. 会创建一个event pygame.mixer.music.set_endevent(MUSIC_ENDED)
2. Check pygame来发布事件

然后你就可以自由地做任何你想做的事情。