actually making it work, adding more customization

Author: Programmerino

README.md

@@ -1,19 +1,12 @@
 # beepFade
 Adds a new fading effect for the Golang Beep library
 ## How to use
-### Fading streamer
-```go
-// Create the set of parameters for it's stream function
-// TimeSpan is how many samples to fade-in for, and then how many samples before the end to fade out for. It is set to 9 seconds here.
-// audioLength is how long the audio it is playing is, which is necessary for fading out properly
-// id should be a unique number so that it can stream while keeping some variable persistent.
-var faderStream = &fader{Streamer: s, Volume: 1, TimeSpan: float64(format.SampleRate.N(time.Second * 9)), audioLength: float64(s.Len()), id: id}
-// Create streamer with fading applied
-changedStreamer := beep.StreamerFunc(faderStream.Stream)
-```
 ### Crossfade between songs
 ```go
-// You can use this high level function to crossfade between streams
-streamer := crossfadeStream(stream1, stream2)
+// CrossfadeStream crossfades between all songs specified in files
+// The sample-rates between the two streams must be the same, otherwise weird things might happen
+// If opts is nil, then reasonable defaults are used
+streamer := beepFade.CrossfadeStream(format, nil, stream1, stream2)
 // This streamer will fade into stream1, and then crossfade between stream1 and stream2, and then fade out of stream2
 ```
+A full example can be found in the example folder

example/go.mod

@@ -0,0 +1,10 @@
+module gitlab.com/256/beepFadeTest
+
+go 1.12
+
+require (
+	github.com/Programmerino/beepFade v0.0.0-20180218012637-3fcac458b4e8
+	github.com/faiface/beep v1.0.1
+)
+
+replace github.com/Programmerino/beepFade => ../

example/go.sum

@@ -0,0 +1,28 @@
+github.com/Programmerino/beepFade v0.0.0-20180218012637-3fcac458b4e8 h1:MNEwdJ+5eTNPHbe1UadIIRe6LA0wuCBjNZ9YM4if3gQ=
+github.com/Programmerino/beepFade v0.0.0-20180218012637-3fcac458b4e8/go.mod h1:vv9YVsGPxWMPIO0Br1QEemezKw1tS13UNJWJ13vQxlM=
+github.com/faiface/beep v1.0.1 h1:SYTt7Bpt0C9KgeLkyNzTTuW9o3D3lTyAPAwCr5EQjO4=
+github.com/faiface/beep v1.0.1/go.mod h1:1yLb5yRdHMsovYYWVqYLioXkVuziCSITW1oarTeduQM=
+github.com/gdamore/encoding v1.0.0/go.mod h1:alR0ol34c49FCSBLjhosxzcPHQbf2trDkoo5dl+VrEg=
+github.com/gdamore/tcell v1.1.1/go.mod h1:K1udHkiR3cOtlpKG5tZPD5XxrF7v2y7lDq7Whcj+xkQ=
+github.com/gopherjs/gopherjs v0.0.0-20180628210949-0892b62f0d9f/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
+github.com/gopherjs/gopherjs v0.0.0-20180825215210-0210a2f0f73c/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
+github.com/gopherjs/gopherwasm v0.1.1/go.mod h1:kx4n9a+MzHH0BJJhvlsQ65hqLFXDO/m256AsaDPQ+/4=
+github.com/gopherjs/gopherwasm v1.0.0/go.mod h1:SkZ8z7CWBz5VXbhJel8TxCmAcsQqzgWGR/8nMhyhZSI=
+github.com/hajimehoshi/go-mp3 v0.1.1 h1:Y33fAdTma70fkrxnc9u50Uq0lV6eZ+bkAlssdMmCwUc=
+github.com/hajimehoshi/go-mp3 v0.1.1/go.mod h1:4i+c5pDNKDrxl1iu9iG90/+fhP37lio6gNhjCx9WBJw=
+github.com/hajimehoshi/oto v0.1.1/go.mod h1:hUiLWeBQnbDu4pZsAhOnGqMI1ZGibS6e2qhQdfpwz04=
+github.com/hajimehoshi/oto v0.3.1 h1:cpf/uIv4Q0oc5uf9loQn7PIehv+mZerh+0KKma6gzMk=
+github.com/hajimehoshi/oto v0.3.1/go.mod h1:e9eTLBB9iZto045HLbzfHJIc+jP3xaKrjZTghvb6fdM=
+github.com/jfreymuth/oggvorbis v1.0.0/go.mod h1:abe6F9QRjuU9l+2jek3gj46lu40N4qlYxh2grqkLEDM=
+github.com/jfreymuth/vorbis v1.0.0/go.mod h1:8zy3lUAm9K/rJJk223RKy6vjCZTWC61NA2QD06bfOE0=
+github.com/lucasb-eyer/go-colorful v0.0.0-20181028223441-12d3b2882a08/go.mod h1:NXg0ArsFk0Y01623LgUqoqcouGDB+PwCCQlrwrG6xJ4=
+github.com/mattn/go-runewidth v0.0.4/go.mod h1:LwmH8dsx7+W8Uxz3IHJYH5QSwggIsqBzpuz5H//U1FU=
+github.com/mewkiz/flac v1.0.5/go.mod h1:EHZNU32dMF6alpurYyKHDLYpW1lYpBZ5WrXi/VuNIGs=
+github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
+github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+golang.org/x/exp v0.0.0-20180710024300-14dda7b62fcd/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
+golang.org/x/image v0.0.0-20180708004352-c73c2afc3b81/go.mod h1:ux5Hcp/YLpHSI86hEcLt0YII63i6oz57MZXIpbrjZUs=
+golang.org/x/mobile v0.0.0-20180806140643-507816974b79/go.mod h1:z+o9i4GpDbdi3rU15maQ/Ox0txvL9dWGYEHz965HBQE=
+golang.org/x/sys v0.0.0-20181228144115-9a3f9b0469bb/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+gopkg.in/DATA-DOG/go-sqlmock.v1 v1.3.0/go.mod h1:OdE7CF6DbADk7lN8LIKRzRJTTZXIjtWgA5THM5lhBAw=

example/main.go

@@ -0,0 +1,51 @@
+package main
+
+import (
+	"log"
+	"os"
+	"time"
+
+	"github.com/Programmerino/beepFade"
+	"github.com/faiface/beep"
+	"github.com/faiface/beep/mp3"
+	"github.com/faiface/beep/speaker"
+)
+
+func main() {
+	f, err := os.Open("song1.mp3")
+	if err != nil {
+		log.Fatal(err)
+	}
+	streamer, format, err := mp3.Decode(f)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer streamer.Close()
+
+	f2, err := os.Open("song2.mp3")
+	if err != nil {
+		log.Fatal(err)
+	}
+	streamer2, _, err := mp3.Decode(f2)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer streamer2.Close()
+
+	opts := beepFade.Options{
+		TimeSpan: 20 * time.Second, // this setting sounds terrible, but hey, this is just an example
+		Volume:   1,
+	}
+
+	final := beepFade.CrossfadeStream(format, &opts, streamer, streamer2)
+
+	speaker.Init(format.SampleRate, format.SampleRate.N(time.Second/10))
+
+	done := make(chan bool)
+	speaker.Play(beep.Seq(final, beep.Callback(func() {
+		done <- true
+	})))
+
+	<-done
+
+}