added ambient sound feature

src/lib/GameEngine.js

@@ -107,6 +107,10 @@ class GameEngine extends THREE.EventDispatcher{
         const dashboard = new DashBoard(this);
         this.dashboard = dashboard;
 
+        this.listener = new THREE.AudioListener();
+        this.camera.add(this.listener);
+        this.ambientSound = new THREE.Audio(this.listener);
+
         this.activeObjects = new THREE.Group();
         scene.add(this.activeObjects);
 
@@ -558,9 +562,19 @@ class GameEngine extends THREE.EventDispatcher{
         this.physics.clear();
         this.clickable.removeAll();
         this.motionQueue.clearAll();
+        this.ambientSound.stop();
+    }
+
+    async playAmbientSound(source, path){
+        let buffer = await GameEngine.loadAudio(source, path);
+        this.ambientSound.setBuffer(buffer);
+        this.ambientSound.setLoop(true);
+        this.ambientSound.play();
     }
 
     static textureLoader = new THREE.TextureLoader();
+    static audioLoader = new THREE.AudioLoader();
+
     static async loadTexture(url, path = assetPath, progress, assignTo) {
         return new Promise((resolve, reject) => {
             GameEngine.textureLoader.load(`${path}${url}`, texture => {
@@ -573,6 +587,14 @@ class GameEngine extends THREE.EventDispatcher{
         })
     }
 
+    static async loadAudio(url, path = assetPath, progress){
+        return new Promise((resolve, reject) => {
+            GameEngine.audioLoader.load(`${path}${url}`, buffer => {
+                resolve(buffer)
+            }, progress, reject)
+        })
+    }
+
     loadTexture = GameEngine.loadTexture
 }