Cross-platform Audio Streaming - Android NDK Game Development - page 131

WavProvider( const clPtr<clBlob>& blob )
{
FRawData = blob;
sWAVHeader H = *(sWAVHeader*)FRawData->GetData();
const unsigned short FORMAT_PCM = 1;
FChannels = H.Channels;
FSamplesPerSec = H.SampleRate;
FBitsPerSample = H.nBitsperSample;
}
24. The destructor is empty, since our Blob object is wrapped into a smart pointer:
virtual ~WavProvider() {}
25. The iWaveDataProvider interface is simple, and here we just implement two
member functions. GetWaveData() returns a pointer to the audio data:
virtual ubyte* GetWaveData()
{
return (ubyte*)FRawData->GetDataConst() +
sizeof( sWAVHeader );
}
26. The GetWaveDataSize() method subtracts the ile header size from the total ile
size:
virtual size_t GetWaveDataSize() const
{
return FRawData->GetSize() - sizeof( sWAVHeader );
};
And we are done with the audio playback and decoding for now.
How it works…
Now we can demonstrate how to use all the audio classes together. As usual, we create an
empty application template, which can be found in the 1_AL_Abstraction folder.
In order to be able to use OpenAL, we must declare a global AudioThread instance:
AudioThread g_Audio;
We start this thread in the OnStart() callback function:
g_Audio.Start( iThread::Priority_Normal );
In this example, we implement the SoundThread class whose Run() method does all the
playback. On this thread, we must wait for g_Audio to get initialized:
while ( !g_Audio.FInitialized ) {}