examples: add playing-audio-with-sdl2-mixer example

Signed-off-by: Lilis Iskandar <lilis@veand.co>

examples/playing-audio-with-sdl2-mixer/playing-audio-with-sdl2-mixer.go

@@ -0,0 +1,73 @@
+package main
+
+import "C"
+import (
+	"log"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/veandco/go-sdl2/mix"
+	"github.com/veandco/go-sdl2/sdl"
+)
+
+func main() {
+	// Initialize SDL2
+	if err := sdl.Init(sdl.INIT_AUDIO); err != nil {
+		log.Println(err)
+		return
+	}
+	defer sdl.Quit()
+
+	// Initialize SDL2 mixer
+	if err := mix.Init(mix.INIT_MP3); err != nil {
+		log.Println(err)
+		return
+	}
+	defer mix.Quit()
+
+	// Open default playback device
+	if err := mix.OpenAudio(mix.DEFAULT_FREQUENCY, mix.DEFAULT_FORMAT, mix.DEFAULT_CHANNELS, mix.DEFAULT_CHUNKSIZE); err != nil {
+		log.Println(err)
+		return
+	}
+	defer mix.CloseAudio()
+
+	// Load compressed audio file (like MP3) with long duration as *mix.Music
+	music, err := mix.LoadMUS("../../assets/test.mp3")
+	if err != nil {
+		log.Println(err)
+	}
+	defer music.Free()
+
+	// Load WAV file with short duration as *mix.Chunk
+	chunk, err := mix.LoadWAV("../../assets/test.wav")
+	if err != nil {
+		log.Println(err)
+	}
+	defer chunk.Free()
+
+	// Play the music once. Change 0 to -1 for infinite playback!.
+	if err := music.Play(0); err != nil {
+		log.Println(err)
+	}
+
+	// Play the chunk once. Change 0 to -1 for infinite playback!
+	if _, err := chunk.Play(-1, 0); err != nil {
+		log.Println(err)
+	}
+
+	// Listen to OS signals
+	c := make(chan os.Signal, 1)
+	signal.Notify(c, os.Interrupt, syscall.SIGTERM)
+
+	// Run infinite loop until we receive SIGINT or SIGTERM!
+	running := true
+	for running {
+		select {
+		case sig := <-c:
+			log.Printf("Received signal %v. Exiting.\n", sig)
+			running = false
+		}
+	}
+}