go-opengl-pixel/audio/compositors.go

41 lines
933 B
Go

package audio
import (
"math"
"time"
)
// Take returns a Streamer which streams s for at most d duration.
func Take(d time.Duration, s Streamer) Streamer {
currSample := 0
numSamples := int(math.Ceil(d.Seconds() * SampleRate))
return StreamerFunc(func(samples [][2]float64) (n int, ok bool) {
if currSample >= numSamples {
return 0, false
}
toStream := numSamples - currSample
if len(samples) < toStream {
toStream = len(samples)
}
sn, sok := s.Stream(samples[:toStream])
currSample += sn
return sn, sok
})
}
// Seq takes zero or more Streamers and returns a Streamer which streams them one by one without pauses.
func Seq(s ...Streamer) Streamer {
i := 0
return StreamerFunc(func(samples [][2]float64) (n int, ok bool) {
for i < len(s) && len(samples) > 0 {
sn, sok := s[i].Stream(samples)
samples = samples[sn:]
n, ok = n+sn, ok || sok
if !sok {
i++
}
}
return n, ok
})
}