added audio test code

2015-10-07 14:42:04 -07:00 · 2015-10-07 14:42:04 -07:00 · 52b9932722
--- a/audiotest.html
+++ b/audiotest.html
@ -0,0 +1,160 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="utf-8">
+    <title></title>
+  </head>
+  <body>
+    <button class="zone1">Zone 1</button>
+    <button class="zone2">Zone 2</button>
+    <button class="zone3">Zone 3</button>
+    <button class="zone4">Zone 4</button>
+    <script>
+
+      var context;
+      var fadeInCurve, fadeOutCurve;
+      var audio;
+
+      function init() {
+        window.AudioContext = window.AudioContext || window.webkitAudioContext;
+        context = new AudioContext();
+
+        bufferLoader = new BufferLoader(
+          context,
+          [
+            'audio/quad1.ogg',
+            'audio/quad2.ogg',
+            'audio/quad3.ogg',
+            'audio/quad4.ogg'
+          ],
+          finishedLoading
+        );
+
+        fadeInCurve = new Float32Array(11);
+        fadeOutCurve = new Float32Array(11);
+        for (var i = 0; i <= 10; i++) {
+          fadeInCurve[i] = eqlerp(i/10);
+          fadeOutCurve[i] = eqlerp(1-i/10);
+        }
+
+        bufferLoader.load();
+      }
+
+      function eqlerp(i) {
+        i = Math.min(1, Math.max(0, i));
+        return Math.cos((1.0 - i) * 0.5 * Math.PI);
+      }
+
+      function Sound(buffer) {
+        this.source = context.createBufferSource();
+        this.source.buffer = buffer;
+        this.gain = context.createGain();
+        this.source.connect(this.gain);
+        this.output = this.gain;
+        this.output.connect(context.destination);
+      }
+      Sound.prototype.loop = function () {
+        this.source.loop = true;
+        this._play();
+      }
+      Sound.prototype.play = function () {
+        this.source.loop = false;
+        this._play();
+      }
+      Sound.prototype.fadeOut = function (duration) {
+        this.gain.gain.setValueCurveAtTime(fadeOutCurve, context.currentTime, duration);
+      }
+      Sound.prototype.fadeIn = function (duration) {
+        this.gain.gain.setValueCurveAtTime(fadeInCurve, context.currentTime, duration);
+      }
+      Sound.prototype._play = function () {
+        this.gain.gain = 0;
+        this.source.start(context.currentTime);
+        this.fadeIn(2);
+      }
+
+
+      function finishedLoading(buffers) {
+        var sounds = buffers.map(function (b) {
+          return new Sound(b);
+        });
+
+        audio = new AudioManager(sounds);
+        audio.setBg(0);
+
+        document.querySelector('.zone1').addEventListener('click', setBg(0));
+        document.querySelector('.zone2').addEventListener('click', setBg(1));
+        document.querySelector('.zone3').addEventListener('click', setBg(2));
+        document.querySelector('.zone4').addEventListener('click', setBg(3));
+      }
+
+
+      function AudioManager(sounds) {
+        this.sounds = sounds;
+        this.active = null;
+      }
+      AudioManager.prototype.setBg = function (n) {
+        if (this.active) {
+          this.active.fadeOut(2);
+        }
+        this.active = this.sounds[n];
+        this.active.loop();
+      }
+      function setBg(n) {
+        return function () {
+          audio.setBg(n);
+        }
+      }
+
+
+      function BufferLoader(context, urlList, callback) {
+        this.context = context;
+        this.urlList = urlList;
+        this.onload = callback;
+        this.bufferList = new Array();
+        this.loadCount = 0;
+      }
+
+      BufferLoader.prototype.loadBuffer = function(url, index) {
+        // Load buffer asynchronously
+        var request = new XMLHttpRequest();
+        request.open("GET", url, true);
+        request.responseType = "arraybuffer";
+
+        var loader = this;
+
+        request.onload = function() {
+          // Asynchronously decode the audio file data in request.response
+          loader.context.decodeAudioData(
+            request.response,
+            function(buffer) {
+              if (!buffer) {
+                alert('error decoding file data: ' + url);
+                return;
+              }
+              loader.bufferList[index] = buffer;
+              if (++loader.loadCount == loader.urlList.length)
+                loader.onload(loader.bufferList);
+            },
+            function(error) {
+              console.error('decodeAudioData error', error);
+            }
+          );
+        }
+
+        request.onerror = function() {
+          alert('BufferLoader: XHR error');
+        }
+
+        request.send();
+      }
+
+      BufferLoader.prototype.load = function() {
+        for (var i = 0; i < this.urlList.length; ++i)
+        this.loadBuffer(this.urlList[i], i);
+      }
+
+      window.onload = init;
+    </script>
+  </body>
+</html>