Subscribe to GameFromScratch on YouTube Support GameFromScratch on Patreon


3. December 2014

 

In this video tutorial we look at all aspects of audio programming in LibGDX.  We look at how to play back sound effects, stream music audio we even record audio from the microphone and play it back.  We also touch on a couple important concepts like cross platform file formats and creating transitions between music tracks.

 

You can see the video in full 1080p resolution here.  All of the code used in this video is presented below.  For more LibGDX video tutorials, go here.

 

 

 

Sound Effects

 

Playing a Sound Effect

ackage com.gamefromscratch;

import com.badlogic.gdx.ApplicationAdapter;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.audio.Sound;
import com.badlogic.gdx.utils.Timer;

public class SoundFXDemo extends ApplicationAdapter {

   Sound sound;
   @Override
   public void create () {
      sound = Gdx.audio.newSound(Gdx.files.internal("glassBreak.wav"));
      sound.play();
   }

   @Override
   public void render () {
   }

   @Override
   public void dispose() {
      sound.dispose();
   }
}

 

Setting Volume

      sound = Gdx.audio.newSound(Gdx.files.internal("glassBreak.wav"));
      long id = sound.play(1.0f);
      sound.setVolume(id,1.0f);

 

Setting Pitch

      sound = Gdx.audio.newSound(Gdx.files.internal("glassBreak.wav"));
      long id = sound.play();
      sound.setPitch(id,0.2f);

 

Setting Pan

      // Track must be in mono format to support panning
      sound = Gdx.audio.newSound(Gdx.files.internal("glassBreakMono.wav"));
      long id = sound.play();
      sound.setPan(id,1.0f,1f);

 

Setting Volume, Pitch and Pan all at once

      sound = Gdx.audio.newSound(Gdx.files.internal("glassBreakMono.wav"));
      sound.play(1.0f,0.0f,0.8f);

 

Looping and Pausing

      sound = Gdx.audio.newSound(Gdx.files.internal("glassBreak.wav"));
      sound.loop();

      // Wait 10 seconds, then pause playback
      Timer.schedule(new Timer.Task(){
         @Override
         public void run(){
            sound.pause();
         }
      }, 10);

 

Multiple Concurrent Sounds

      sound = Gdx.audio.newSound(Gdx.files.internal("glassBreakMono.wav"));

      // Play 2, one fast, one slow
      final long fastSound = sound.loop(1f,2.5f,0f);
      final long slowSound = sound.loop(1f,0.5f,0f);

      // Wait 5 seconds, then stop ALL
      Timer.schedule(new Timer.Task() {
         @Override
         public void run() {
            //sound.stop();
            // Or stop just one
            sound.stop(fastSound);
         }
      }, 5);

 

 

Music

 

package com.gamefromscratch;

import com.badlogic.gdx.ApplicationAdapter;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.audio.Music;
import com.badlogic.gdx.utils.Timer;

public class MusicDemo extends ApplicationAdapter {

   Music song1,song2;

   @Override
   public void create () {
      song1 = Gdx.audio.newMusic(Gdx.files.internal("song1.mp3"));
      song2 = Gdx.audio.newMusic(Gdx.files.internal("song2.mp3"));

      song1.play();


      // Then set it so song 2 plays when song1 ends
      song1.setOnCompletionListener(new Music.OnCompletionListener() {
         @Override
         public void onCompletion(Music music) {
            song2.play();
         }
      });

      // You can pan and set volume like sound fx, but cant play multiple instances and cant set pitch
      // You can however get the position of the sound ( but not set it )
      // Let's do a timer that lower the volume over the last 5 seconds of the song
      // Built in options are pretty limited, so there is no way to poll for the length of a song
      // Without using the audio-extension
      Timer.schedule(new Timer.Task() {
         @Override
         public void run() {
            if(song1.isPlaying())
               if(song1.getPosition() >= 10)
                  song1.setVolume(song1.getVolume() - 0.2f);
         }
      },10,1,4);

   }

   @Override
   public void render () {
   }

   @Override
   public void dispose() {
      song1.dispose();
      song2.dispose();
   }
}

 

Audio Recording and Playback

 

package com.gamefromscratch;

import com.badlogic.gdx.ApplicationAdapter;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.audio.AudioDevice;
import com.badlogic.gdx.audio.AudioRecorder;

public class AudioRecorderDemo extends ApplicationAdapter {

   @Override
   public void create () {

      // This code may not actually work during video recording due to Microphone being in use.
      AudioRecorder recorder = Gdx.audio.newAudioRecorder(44100,true);
      short[] audioBuffer = new short[44100 * 5];

      // read() will fail if device doesnt support given resolution or a mic is not attached
      recorder.read(audioBuffer,0,audioBuffer.length);

      AudioDevice audioDevice = Gdx.audio.newAudioDevice(44100,true);
      audioDevice.writeSamples(audioBuffer,0,audioBuffer.length);
      audioDevice.dispose();
      recorder.dispose();
      Gdx.app.exit();
   }

   @Override
   public void render () {
   }
}

Programming , ,

blog comments powered by Disqus

Month List

Popular Comments