feat(sointu-player): implement a basic commandline tool to play songs

go4k/cmd/sointu-player/main.go

@@ -0,0 +1,91 @@
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"github.com/vsariola/sointu/go4k"
+	"github.com/vsariola/sointu/go4k/audio"
+	"github.com/vsariola/sointu/go4k/audio/oto"
+	"github.com/vsariola/sointu/go4k/bridge"
+	"io/ioutil"
+	"os"
+)
+
+func main() {
+	// parse flags
+	quiet := flag.Bool("quiet", false, "no sound output")
+	out := flag.String("out", "", "write output to file")
+	help := flag.Bool("h", false, "show help")
+	flag.Usage = printUsage
+	flag.Parse()
+	if flag.NArg() == 0 || *help {
+		flag.Usage()
+		os.Exit(0)
+	}
+
+	// read input song
+	var song go4k.Song
+	if bytes, err := ioutil.ReadFile(flag.Arg(0)); err != nil {
+		fmt.Printf("Cannot read song file: %v", err)
+		os.Exit(1)
+	} else if err := json.Unmarshal(bytes, &song); err != nil {
+		fmt.Printf("Cannot unmarshal song file: %v", err)
+		os.Exit(1)
+	}
+
+	// set up synth
+	synth, err := bridge.Synth(song.Patch)
+	if err != nil {
+		fmt.Printf("Cannot create synth: %v", err)
+		os.Exit(1)
+	}
+
+	// render the actual data for the entire song
+	fmt.Print("Rendering.. ")
+	buff, err := go4k.Play(synth, song)
+	if err != nil {
+		fmt.Printf("Error rendering with go4k: %v\n", err.Error())
+		os.Exit(1)
+	} else {
+		fmt.Printf("Rendered %v samples.\n", len(buff))
+	}
+
+	// play output if not in quiet mode
+	if !*quiet {
+		fmt.Print("Playing.. ")
+		player, err := oto.NewPlayer()
+		if err != nil {
+			fmt.Printf("Error creating oto player: %v\n", err.Error())
+			os.Exit(1)
+		}
+		defer player.Close()
+		if err := player.Play(buff); err != nil {
+			fmt.Printf("Error playing: %v\n", err.Error())
+			os.Exit(1)
+		}
+		fmt.Println("Played.")
+	}
+
+	// write output to file if output given
+	if out != nil && *out != "" {
+		fmt.Printf("Writing output to %v.. ", *out)
+		if bbuffer, err := audio.FloatBufferTo16BitLE(buff); err != nil {
+			fmt.Printf("Error converting buffer: %v\n", err.Error())
+			os.Exit(1)
+		} else if err := ioutil.WriteFile(*out, bbuffer, os.ModePerm); err != nil {
+			fmt.Printf("Error writing: %v\n", err.Error())
+			os.Exit(1)
+		} else {
+			fmt.Printf("Wrote %v bytes.\n", len(bbuffer))
+		}
+	}
+
+	fmt.Println("All done.")
+	os.Exit(0)
+}
+
+func printUsage() {
+	fmt.Fprintf(os.Stderr, "Usage: %s [OPTIONS] [SONG FILE] [OUTPUT FILE]\n", os.Args[0])
+	flag.PrintDefaults()
+}