// au demonstrates basic audio library, vu/audio/al, capabilities.
// It checks that OpenAL is installed and the bindings are working
// by loading and playing a sound.
func au() {
al.Init() // map the bindings to the OpenAL dynamic library.
// open the default device.
if dev := al.OpenDevice(""); dev != 0 {
defer al.CloseDevice(dev)
// create a context on the device.
if ctx := al.CreateContext(dev, nil); ctx != 0 {
defer al.MakeContextCurrent(0)
defer al.DestroyContext(ctx)
al.MakeContextCurrent(ctx)
// create buffers and sources
var buffer, source uint32
al.GenBuffers(1, &buffer)
al.GenSources(1, &source)
// read in the audio data.
ldr := load.NewLoader()
wh, data, err := ldr.Wav("bloop")
if err != nil {
log.Printf("au: error loading audio file %s %s", "bloop", err)
return
}
// copy the audio data into the buffer
tag := &autag{}
format := tag.audioFormat(wh)
if format < 0 {
log.Printf("au: error recognizing audio format")
return
}
al.BufferData(buffer, int32(format), al.Pointer(&(data[0])), int32(wh.DataSize), int32(wh.Frequency))
// attach the source to a buffer.
al.Sourcei(source, al.BUFFER, int32(buffer))
// check for any audio library errors that have happened up to this point.
if openAlErr := al.GetError(); openAlErr != 0 {
log.Printf("au: OpenAL error %d", openAlErr)
return
}
// Start playback and give enough time for the playback to finish.
al.SourcePlay(source)
time.Sleep(500 * time.Millisecond)
return
}
log.Printf("au: error, failed to get a context")
}
log.Printf("au: error, failed to get a device")
}
// BindSound copies sound data to the sound card. If successfull then the
// sound reference, snd, and sound data buffer reference, buff are updated
// with valid references.
func (a *openal) BindSound(snd, buff *uint64, d *Data) (err error) {
if alerr := al.GetError(); alerr != al.NO_ERROR {
log.Printf("openal.BindSound need to find and fix prior error %X", alerr)
}
// create the sound buffer and copy the audio data into the buffer
var buff32, snd32 uint32
var format int32
if format, err = a.format(d); err == nil {
al.GenBuffers(1, &buff32)
al.BufferData(buff32, format, al.Pointer(&(d.AudioData[0])), int32(d.DataSize), int32(d.Frequency))
*buff = uint64(buff32)
if alerr := al.GetError(); alerr != al.NO_ERROR {
err = fmt.Errorf("Failed binding sound %s", d.Name)
} else {
al.GenSources(1, &snd32)
al.Sourcei(snd32, al.BUFFER, int32(*buff))
*snd = uint64(snd32)
}
}
return err
}