【Unity基础知识】Cocos2d-x音乐和音效

简介

Cocos2d-x 提供了一个 SimpleAudioEngine 类支持游戏内的音乐和音效。它可以被用来增加背景音乐，控制游戏音效。

SimpleAudioEngine 是一个共享的单例对象，你可以在代码中的任何地方通过很简单的方式获取到。以下，我们会尽可能的为你展示它的各种使用方法。先来了解一下支持的文件格式。

支持的音乐格式：

支持的音效格式：

播放背景音乐

通过下面的方式，播放一个音频文件作为背景音乐，可以控制背景音乐是否循环播放：

#include "SimpleAudioEngine.h"

using namespace CocosDenshion;

auto audio = SimpleAudioEngine::getInstance();

// set the background music and continuously play it.

audio->playBackgroundMusic("mymusic.mp3", true);

// set the background music and play it just once.

audio->playBackgroundMusic("mymusic.mp3", false);

播放音效

通过下面的方式，将一个音频文件作为音效：

#include "SimpleAudioEngine.h"

using namespace CocosDenshion;

auto audio = SimpleAudioEngine::getInstance();

// play a sound effect, just once.

audio->playEffect("myEffect.mp3", false, 1.0f, 1.0f, 1.0f);

声音控制

开始播放音乐和音效后，你可能需要对它们进行一些控制，比如暂停、停止、恢复。这很容易完成，下面介绍：

1.暂停声音：

#include "SimpleAudioEngine.h"

using namespace CocosDenshion;

auto audio = SimpleAudioEngine::getInstance();

// pause background music.

audio->pauseBackgroundMusic();

// pause a sound effect.

audio->pauseEffect();

// pause all sound effects.

audio->pauseAllEffects();

2.停止声音：

#include "SimpleAudioEngine.h"

using namespace CocosDenshion;

auto audio = SimpleAudioEngine::getInstance();

// stop background music.

audio->stopBackgroundMusic();

// stop a sound effect.

audio->stopEffect();

// stops all running sound effects.

audio->stopAllEffects();

3.恢复声音：

#include "SimpleAudioEngine.h"

using namespace CocosDenshion;

auto audio = SimpleAudioEngine::getInstance();

// resume background music.

audio->resumeBackgroundMusic();

// resume a sound effect.

audio->resumeEffect();

// resume all sound effects.

audio->resumeAllEffects();

预加载

加载音乐和音效通常是个耗时间的过程，为了防止由加载产生的延时导致实际播放与游戏播放不协调的现象，在播放音乐和音效前，可以预加载音乐文件：

#include "SimpleAudioEngine.h"

using namespace CocosDenshion;

auto audio = SimpleAudioEngine::getInstance();

// pre-loading background music and effects. You could pre-load// effects, perhaps on app startup so they are already loaded// when you want to use them.

audio->preloadBackgroundMusic("myMusic1.mp3");

audio->preloadBackgroundMusic("myMusic2.mp3");

audio->preloadEffect("myEffect1.mp3");

audio->preloadEffect("myEffect2.mp3");

// unload a sound from cache. If you are finished with a sound and// you wont use it anymore in your game. unload it to free up// resources.

audio->unloadEffect("myEffect1.mp3");