/** Decodes an opened OggVorbis file into an OpenAL buffer
* \param psTrack pointer to object which will contain the final buffer
* \param PHYSFS_fileHandle file handle given by PhysicsFS to the opened file
* \return on success the psTrack pointer, otherwise it will be free'd and a NULL pointer is returned instead
*/
static inline TRACK* sound_DecodeOggVorbisTrack(TRACK *psTrack, PHYSFS_file* PHYSFS_fileHandle)
{
#ifndef WZ_NOSOUND
ALenum format;
ALuint buffer;
struct OggVorbisDecoderState *decoder;
soundDataBuffer *soundBuffer;
if ( !openal_initialized )
{
return NULL;
}
decoder = sound_CreateOggVorbisDecoder(PHYSFS_fileHandle, true);
if (decoder == NULL)
{
debug(LOG_WARNING, "Failed to open audio file for decoding");
free(psTrack);
return NULL;
}
soundBuffer = sound_DecodeOggVorbis(decoder, 0);
sound_DestroyOggVorbisDecoder(decoder);
if (soundBuffer == NULL)
{
free(psTrack);
return NULL;
}
if (soundBuffer->size == 0)
{
debug(LOG_WARNING, "sound_DecodeOggVorbisTrack: OggVorbis track is entirely empty after decoding");
// NOTE: I'm not entirely sure if a track that's empty after decoding should be
// considered an error condition. Therefore I'll only error out on DEBUG
// builds. (Returning NULL here __will__ result in a program termination.)
#ifdef DEBUG
free(soundBuffer);
free(psTrack);
return NULL;
#endif
}
// Determine PCM data format
format = (soundBuffer->channelCount == 1) ? AL_FORMAT_MONO16 : AL_FORMAT_STEREO16;
// Create an OpenAL buffer and fill it with the decoded data
alGenBuffers(1, &buffer);
sound_GetError();
alBufferData(buffer, format, soundBuffer->data, soundBuffer->size, soundBuffer->frequency);
sound_GetError();
free(soundBuffer);
// save buffer name in track
psTrack->iBufferName = buffer;
#endif
return psTrack;
}
/** Plays the audio data from the given file
* \param fileHandle,volume,onFinished,user_data see sound_PlayStream()
* \param streamBufferSize the size to use for the decoded audio buffers
* \param buffer_count the amount of audio buffers to use
* \see sound_PlayStream() for details about the rest of the function
* parameters and other details.
*/
AUDIO_STREAM *sound_PlayStreamWithBuf(PHYSFS_file *fileHandle, float volume, void (*onFinished)(void *), void *user_data, size_t streamBufferSize, unsigned int buffer_count)
{
AUDIO_STREAM *stream;
ALuint *buffers = (ALuint *)alloca(sizeof(ALuint) * buffer_count);
ALint error;
unsigned int i;
if (!openal_initialized)
{
debug(LOG_WARNING, "OpenAL isn't initialized, not creating an audio stream");
return NULL;
}
stream = (AUDIO_STREAM *)malloc(sizeof(AUDIO_STREAM));
if (stream == NULL)
{
debug(LOG_FATAL, "sound_PlayStream: Out of memory");
abort();
return NULL;
}
// Clear error codes
alGetError();
// Retrieve an OpenAL sound source
alGenSources(1, &(stream->source));
error = sound_GetError();
if (error != AL_NO_ERROR)
{
// Failed to create OpenAL sound source, so bail out...
debug(LOG_SOUND, "alGenSources failed, most likely out of sound sources");
free(stream);
return NULL;
}
stream->fileHandle = fileHandle;
stream->decoder = sound_CreateOggVorbisDecoder(stream->fileHandle, false);
if (stream->decoder == NULL)
{
debug(LOG_ERROR, "sound_PlayStream: Failed to open audio file for decoding");
free(stream);
return NULL;
}
stream->volume = volume;
stream->bufferSize = streamBufferSize;
alSourcef(stream->source, AL_GAIN, stream->volume);
// HACK: this is a workaround for a bug in the 64bit implementation of OpenAL on GNU/Linux
// The AL_PITCH value really should be 1.0.
alSourcef(stream->source, AL_PITCH, 1.001f);
// Create some OpenAL buffers to store the decoded data in
alGenBuffers(buffer_count, buffers);
sound_GetError();
// Fill some buffers with audio data
for (i = 0; i < buffer_count; ++i)
{
// Decode some audio data
soundDataBuffer *soundBuffer = sound_DecodeOggVorbis(stream->decoder, stream->bufferSize);
// If we actually decoded some data
if (soundBuffer && soundBuffer->size > 0)
{
// Determine PCM data format
ALenum format = (soundBuffer->channelCount == 1) ? AL_FORMAT_MONO16 : AL_FORMAT_STEREO16;
// Copy the audio data into one of OpenAL's own buffers
alBufferData(buffers[i], format, soundBuffer->data, soundBuffer->size, soundBuffer->frequency);
sound_GetError();
// Clean up our memory
free(soundBuffer);
}
else
{
// If no data has been decoded we're probably at the end of our
// stream. So cleanup the excess stuff here.
// First remove the data buffer itself
free(soundBuffer);
// Then remove OpenAL's buffers
alDeleteBuffers(buffer_count - i, &buffers[i]);
sound_GetError();
break;
}
}
// Bail out if we didn't fill any buffers
if (i == 0)
{
debug(LOG_ERROR, "Failed to fill buffers with decoded audio data!");
// Destroy the decoder
sound_DestroyOggVorbisDecoder(stream->decoder);
// Destroy the OpenAL source
alDeleteSources(1, &stream->source);
// Free allocated memory
free(stream);
return NULL;
}
// Attach the OpenAL buffers to our OpenAL source
// (i = the amount of buffers we worked on in the above for-loop)
alSourceQueueBuffers(stream->source, i, buffers);
sound_GetError();
// Start playing the source
alSourcePlay(stream->source);
sound_GetError();
// Set callback info
stream->onFinished = onFinished;
stream->user_data = user_data;
// Prepend this stream to the linked list
stream->next = active_streams;
active_streams = stream;
return stream;
}
