Merge branch 'master' of https://github.com/rocketinventor/system-bus…

…-radio into rocketinventor-master

* 'master' of https://github.com/rocketinventor/system-bus-radio:
  Added comments to source code
  Implemented Web Workers
  Preperations for web using a worker
  moved var definition
  created var for window log
  fixed description meta
  Added a delay function and fixed time being *1000.
  improved link styling
  removed red outline around text box
  removed more unused CSS
  removed unused and unrelated  CSS classes
  Improved formatting

In Javascript/airgap.html

@@ -15,7 +15,8 @@
 	</div>
 	<div class="content">
 		</br>
-		<input type="button" value="Play Song" onclick="start()"></br></br>
+		<input type="button" value="Play Song" onclick="start()">
+		<input type="button" value="Stop Song" onclick="end()"></br></br>
 		<textarea id="logs" style="width:70%;min-height:100px">Tested with Chrome at 1560Khz</textarea>
 		<p style="font-size:14px">Feel free to edit the code below or copy and paste any <em>valid</em> code.<br>Column one is time in <i>milliseconds</i>, and column two is <i>frequency</i>.</p>
 		<textarea id="tones" style="width:70%;min-height:200px">

In Javascript/airgap.js

@@ -1,48 +1,25 @@
-//Credits to https://github.com/fulldecent/system-bus-radio
-//As well as Jordan Harband for the nodejs simd library
-//Tested to be working on Chrome at 1560khz
+var player; // Define "player" var to make my code linter happy
 
-function now() {
-	return window.performance.now() * 1000000;
-}
+function start() { // Start Web Worker & send song data to player
+	var logs = document.getElementById('logs'); // Define log element
 
-var NSEC_PER_SEC = 1000000000;
-var register = 3.1415;
-var logs = document.getElementById('logs');
+	// Create Web Worker if it doesn't already exist
+	if (window.Worker && typeof(player) == "undefined") {
+		var player = new Worker("worker.js");
+		window.player = player; // Make variable Global
+		player.onmessage = function(event) {
+			var data = event.data;
+			window.logs.value += data;
+		};
 
-function square_am_signal(time, freq) {
-	window.logs.value += "\nPlaying / " + time + " seconds / " + freq + "Hz";
-	var period = NSEC_PER_SEC / freq;
-	var start = now();
-	var end = now() + time * NSEC_PER_SEC;
-	while (now() < end) {
-		var mid = start + period / 2;
-		var reset = start + period;
-		while (now() < mid) {
-			for (var i = 0; i < 100; i++) {
-				register = 1 - Math.log(register) / 1.7193;
-			}
-		}
-		while (now() < reset) {}
-		start = reset;
+		// Send song data to player
+		var song = document.getElementById("tones").innerHTML;
+		player.postMessage(song);
 	}
 }
 
-function start() {
-	var song = document.getElementById("tones").value.split("\n");
-	var length = song.length;
-	var line, time, freq;
-	for (var i = 0; i < length; i++) {
-		line = song[i].split(" ");
-		if (+line[1] == 0) {
-			pause(line[0]);
-		}
-		else {
-			freq = +line[1];
-			time = (+line[0])*.001;
-			square_am_signal(time, freq);
-		}
-	}
+function end() { // Stops the Web Worker
+	player.terminate();
 }
 
 function pause(time) {

In Javascript/worker.js

@@ -0,0 +1,60 @@
+//Credits to https://github.com/fulldecent/system-bus-radio
+//As well as Jordan Harband for the nodejs simd library
+//Tested to be working on Chrome at 1560khz
+
+var window = self; // Create "window" object
+
+function now() {
+	return window.performance.now() * 1000000;
+}
+
+var NSEC_PER_SEC = 1000000000;
+var register = 3.1415;
+
+function square_am_signal(time, freq) { // This funcion generates the radio waves
+	postMessage("\nPlaying / " + time + " seconds / " + freq + "Hz");
+	var period = NSEC_PER_SEC / freq;
+	var start = now();
+	var end = now() + time * NSEC_PER_SEC;
+	while (now() < end) {
+		var mid = start + period / 2;
+		var reset = start + period;
+		while (now() < mid) {
+			for (var i = 0; i < 100; i++) {
+				register = 1 - Math.log(register) / 1.7193;
+			}
+		}
+		while (now() < reset) {}
+		start = reset;
+	}
+}
+
+function play(song) { // Parse song data, and call on required scripts to run it
+	song = song.split("\n");
+	var length = song.length;
+	var line, time, freq;
+	for (var i = 0; i < length; i++) {
+		line = song[i].split(" ");
+		if (+line[1] == 0) {
+			pause(line[0]);
+		}
+		else {
+			freq = +line[1];
+			time = (+line[0])*.001;
+			square_am_signal(time, freq);
+		}
+	}
+
+	close(); // Close Web Worker
+}
+
+function pause(time) { // A useless function to run when there is no noise to play
+	postMessage("\nPaused / " + time*.001 + " seconds");
+	var dt = new Date();
+	while ((new Date()) - dt <= time) { /* Do nothing */ }
+}
+
+onmessage = function(event) { // Recieve song data from main page
+	var data = event.data;
+	play(data);
+};