subsonic-tui/vendor/github.com/gopxl/beep/mixer.go
Sagi Dayan 48661005be
initial commit
Signed-off-by: Sagi Dayan <sagidayan@gmail.com>
2024-09-01 16:30:56 +03:00

70 lines
1.9 KiB
Go

package beep
// Mixer allows for dynamic mixing of arbitrary number of Streamers. Mixer automatically removes
// drained Streamers. Mixer's stream never drains, when empty, Mixer streams silence.
type Mixer struct {
streamers []Streamer
}
// Len returns the number of Streamers currently playing in the Mixer.
func (m *Mixer) Len() int {
return len(m.streamers)
}
// Add adds Streamers to the Mixer.
func (m *Mixer) Add(s ...Streamer) {
m.streamers = append(m.streamers, s...)
}
// Clear removes all Streamers from the mixer.
func (m *Mixer) Clear() {
m.streamers = m.streamers[:0]
}
// Stream streams all Streamers currently in the Mixer mixed together. This method always returns
// len(samples), true. If there are no Streamers available, this methods streams silence.
func (m *Mixer) Stream(samples [][2]float64) (n int, ok bool) {
var tmp [512][2]float64
for len(samples) > 0 {
toStream := len(tmp)
if toStream > len(samples) {
toStream = len(samples)
}
// clear the samples
for i := range samples[:toStream] {
samples[i] = [2]float64{}
}
for si := 0; si < len(m.streamers); si++ {
// mix the stream
sn, sok := m.streamers[si].Stream(tmp[:toStream])
for i := range tmp[:sn] {
samples[i][0] += tmp[i][0]
samples[i][1] += tmp[i][1]
}
if !sok {
// remove drained streamer
sj := len(m.streamers) - 1
m.streamers[si], m.streamers[sj] = m.streamers[sj], m.streamers[si]
m.streamers = m.streamers[:sj]
si--
}
}
samples = samples[toStream:]
n += toStream
}
return n, true
}
// Err always returns nil for Mixer.
//
// There are two reasons. The first one is that erroring Streamers are immediately drained and
// removed from the Mixer. The second one is that one Streamer shouldn't break the whole Mixer and
// you should handle the errors right where they can happen.
func (m *Mixer) Err() error {
return nil
}