// NewPlayer returns a new Player.
// It initializes the underlying audio devices and the related resources.
// If zero values are provided for format and sample rate values, the player
// determines them from the source's WAV header.
// An error is returned if the format and sample rate can't be determined.
func NewPlayer(src ReadSeekCloser, format Format, samplesPerSecond int64) (*Player, error) {
if err := al.OpenDevice(); err != nil {
return nil, err
}
s := al.GenSources(1)
if code := al.Error(); code != 0 {
return nil, fmt.Errorf("audio: cannot generate an audio source [err=%x]", code)
}
p := &Player{
t: &track{format: format, src: src, samplesPerSecond: samplesPerSecond},
source: s[0],
}
if err := p.discoverHeader(); err != nil {
return nil, err
}
if p.t.format == 0 {
return nil, errors.New("audio: cannot determine the format")
}
if p.t.samplesPerSecond == 0 {
return nil, errors.New("audio: cannot determine the sample rate")
}
return p, nil
}
// lastErr returns the last error or nil if the last operation
// has been succesful.
func lastErr() error {
if code := al.Error(); code != 0 {
return fmt.Errorf("audio: openal failed with %x", code)
}
return nil
}