game over slow down fx (fixes #39)

src/components/beat-loader.js

@@ -24,8 +24,10 @@ AFRAME.registerComponent('beat-loader', {
     this.bpm = undefined;
     this.first = null;
     this.lastTime = undefined;
+    this.speed = 1.0; // for slowing down on gameover
 
     this.el.addEventListener('cleargame', this.clearBeats.bind(this));
+    this.el.addEventListener('slowdown', this.slowDown.bind(this));
   },
 
   update: function (oldData) {
@@ -84,6 +86,8 @@ AFRAME.registerComponent('beat-loader', {
     var msPerBeat;
     var noteTime;
 
+    delta *= this.speed;
+
     if (this.data.isPaused || !this.data.challengeId || !this.beatData || !audioEl) { return; }
 
     notes = this.beatData._notes;
@@ -195,8 +199,13 @@ AFRAME.registerComponent('beat-loader', {
     this.audioSync = null;
     this.first = null;
     this.lastTime = 0;
+    this.speed = 1.0;
     for (let i = 0; i < this.beatContainer.children.length; i++) {
       this.beatContainer.children[i].components.beat.returnToPool(true);
     }
+  },
+
+  slowDown: function (ev) {
+    this.speed = ev.detail.progress;
   }
 });