c++ - 如何在XAudio2上同时播放多种声音？

Question

我目前正在尝试使用XAudio2在Windows中制作一个游戏应用程序，但我不知道如何在播放声音时使该应用程序不阻塞。我尝试在this repository.中的示例中调用新线程

但这只会导致错误。我尝试在函数中传递对母带声音的引用，但随后它仅引发“XAudio2:必须先创建母带声音”错误。我想念什么吗？我只是想让它一次播放两个声音并从那里建立声音。我查看了文档，但是它非常模糊。

Answer 1

XAudio2是一个非阻塞API。要同时播放两种声音，您至少需要两种“源声音”和一种“母带声音”。

DX::ThrowIfFailed(
    CoInitializeEx( nullptr, COINIT_MULTITHREADED )
);

Microsoft::WRL::ComPtr<IXAudio2> pXAudio2;
// Note that only IXAudio2 (and APOs) are COM reference counted
DX::ThrowIfFailed(
    XAudio2Create( pXAudio2.GetAddressOf(), 0 )
);

IXAudio2MasteringVoice* pMasteringVoice = nullptr;
DX::ThrowIfFailed(
    pXAudio2->CreateMasteringVoice( &pMasteringVoice )
);

IXAudio2SourceVoice* pSourceVoice1 = nullptr;
DX::ThrowIfFailed(
    pXaudio2->CreateSourceVoice( &pSourceVoice1, &wfx ) )
    // The default 'pSendList' will be just to the pMasteringVoice
);

IXAudio2SourceVoice* pSourceVoice2 = nullptr;
DX::ThrowIfFailed(
    pXaudio2->CreateSourceVoice( &pSourceVoice2, &wfx) )
    // Doesn't have to be same format as other source voice
    // And doesn't have to match the mastering voice either
);

DX::ThrowIfFailed(
    pSourceVoice1->SubmitSourceBuffer( &buffer )
);

DX::ThrowIfFailed(
    pSourceVoice2->SubmitSourceBuffer( &buffer /* could be different WAV data or not */)
);

DX::ThrowIfFailed(
    pSourceVoice1->Start( 0 );
);

DX::ThrowIfFailed(
    pSourceVoice2->Start( 0 );
);

You should take a look at the samples on GitHub as well as DirectX Tool Kit for Audio

如果您想确保两种声音都在同一时间开始，则可以使用:

DX::ThrowIfFailed(
    pSourceVoice1->Start( 0, 1 );
);

DX::ThrowIfFailed(
    pSourceVoice2->Start( 0, 1 );
);

DX::ThrowIfFailed(
    pSourceVoice2->CommitChanges( 1 );
);