Abstract canvas width/height into variables

vocoder/static/vocoder.js

@@ -8,6 +8,8 @@
 //
 
 var archiveUrl = serverUrl + "/add-to-archive/";
+var canvasHeight = 500;
+var canvasWidth = 500;
 var microphone;
 var newSoundJustRecorded = false;
 var playButton;
@@ -120,7 +122,7 @@ class GeneratedShape {
     /**
      * Show the shape on the canvas.
      **/
-    ellipse(random(600), random(600), 10, 10); // TODO: experimenting for now ...
+    ellipse(random(canvasWidth), random(canvasHeight), 10, 10); // TODO: experimenting for now ...
     this.displayed = true;
   }
 }
@@ -136,7 +138,7 @@ function setup() {
   /**
    * The p5.js initial setup function.
    **/
-  createCanvas(600, 600); // TODO: experimenting for now ...
+  createCanvas(canvasWidth, canvasHeight); // TODO: experimenting for now ...
   setupRecording();
 }