Game Development Reference
In-Depth Information
Now we can create the audio source:
clPtr<AudioSource> Src = new AudioSource();
Finally, we need to create a
WavProvider
object, which decodes audio iles, attach it to the
Src
source, start playback and wait for its completion:
clPtr<Blob> Data = LoadFileAsBlob("test.wav");
Src->BindWaveform( new WavProvider( Data ) );
Src->Play();
while ( Src->IsPlaying() ) {}
After the sound playback is inished, we reset the
Src
pointer to
NULL
and send the
termination signal to the
g_Audio
thread:
Src = NULL;
g_Audio.Exit(true);
To obtain the
Data
object, we have to implement the following function, which reads the ile
contents into a memory block:
clPtr<Blob> LoadFileAsBlob( const std::string& FName )
{
clPtr<iIStream> input = g_FS->CreateReader( FName );
clPtr<Blob> Res = new Blob();
Res->CopyMemoryBlock( input->MapStream(), input->GetSize() );
return Res;
}
We use the global initialized instance of
FileSystem
, the
g_FS
object. Please note that
on the Android OS, we cannot use the standard paths and therefore resort to our virtual ile
system implementation.
There's more…
We can implement a number of helper routines to ease the use of the
AudioSource
class.
The irst useful routine is source pausing. OpenAL provides the
alSourcePause()
function,
which is not enough, since we have to be in control of all the unqueued buffers being played.
This unqueuing is not important at this point as we have only one buffer, but when we get to
streaming the sound, we have to take care of the buffers queue. The following code should be
added to the
AudioSource
class to implement pausing:
void Pause()
{
alSourcePause( FSourceID );
UnqueueAll();
}
