More or less finished product: added options like speed and density and age color effects

life.html

@@ -10,13 +10,15 @@
 			var width_c;
 			var cells;
 			var timer;
+			var effects;
 
-
+			// set start/stop button value
 			function btn_control_set_name(name) {
 				var btn = document.getElementById('control-btn');
 				btn.value = name;
 			}
 
+			// generate an 2d array of cells based on current geometry
 			function gen_cells() {
 				var new_cells = new Array(height_c);
 				for(var i = 0; i < height_c; i++) {
@@ -24,33 +26,54 @@
 				}
 				for (var y = 0; y < height_c; y++) {
 					for (var x = 0; x < width_c; x++) {
-						new_cells[y][x] = false;
+						new_cells[y][x] = 0;
 					}
 				}
 				return new_cells;
 			}
-			
+
+			// init the cells	
 			function init_cells() {
 				cells = gen_cells();
 			}
 
+			// Generate and populate the geometry variables
+			// possibly over complicated from my experiment with an elastic resizeable board
+			function get_demensions() {
+				var canvas = document.getElementById('board');
+				size = parseInt( document.getElementById('density').value);
+				width_px = canvas.offsetWidth - (canvas.offsetWidth%size);
+				canvas.width = width_px;
+				width_c = width_px/ size;
+				height_px = canvas.offsetHeight - (canvas.offsetHeight%size);
+				canvas.height = height_px;
+				height_c = height_px/size;
+				//console.log(width_px + 'x' + height_px + ' => ' + width_c + 'x' +height_c);
+			}
+
+			// init the board
+			//   set vars
+			//   get geometry
+			//   generate cells for 1st time
+			//   draw
 			function board_init() {
 				var canvas = document.getElementById('board');
-				size = 10;
+				document.getElementById('density').value = 10;
-				width_px = canvas.width;
+				get_demensions();
-				width_c = width_px/ size;
-				height_px = canvas.height;
-				height_c = height_px/size;
 				btn_control_set_name('Start');
-				hertz = 4;
+				document.getElementById('speed').value = 8;
+				change_speed();
 				init_cells();
+				document.getElementById('effects').value=0;
+				effects=0;
 				redraw();
 			}
 
+			// Draw the current board: gird, then cells
 			function redraw() {
-				console.log('redraw()');
 				var canvas = document.getElementById('board');
 				var c = canvas.getContext('2d');
+				get_demensions();
 				
 				c.globalCompositeOperation = 'destination-over';
 
@@ -58,7 +81,6 @@
 				
 				c.fillStyle='rgba(0,0,0,0.)';
 				c.strokeStyle= 'rgba(192,192,192,1)';
-				c.save();
 
 				c.beginPath();
 
@@ -66,28 +88,54 @@
 				c.stroke();
 				
 
-				c.strokeStyle= 'rgba(0,0,0,1)';
-				c.fillStyle = c.strokeStyle;
-				c.beginPath();
 				draw_cells(c);
-				c.stroke();
-				c.fill();
 			}
 
+			// Generate a cycling darkening with age rainbow color
+			// based on math/code from http://www.krazydad.com/makecolors.php
+			function setStrokeAgeRainbow(l, c) {
+				var frequency = 0.3;
+				var center = 200; //128;
+				var width = 55; //127;
+
+				var red =  Math.floor( (Math.sin(frequency*l + 0) * width + center) -l) ;
+				var green =  Math.floor( (Math.sin(frequency*l + 2) * width + center) -l);
+				var blue =  Math.floor( (Math.sin(frequency*l + 4) * width + center) -l);
+							
+				red = Math.max(0, red); 
+				green = Math.max(0, green);
+				blue = Math.max(0, blue);
+
+				c.strokeStyle= 'rgba('+red+','+green+','+blue+','+1+')';
+			}
+
+			// Draw all the cells onto the board inside the grid
 			function draw_cells(c) {
 				for (var y = 0; y < height_c; y++) {
 					for (var x =0; x < width_c; x ++) {
-						if (cells[y][x] == true) {
+						if (cells[y][x] != 0) {
+
+							if(effects == 0) {
+								c.strokeStyle = 'rgba(0,0,0,1)';
+							} else {
+								setStrokeAgeRainbow(cells[y][x], c);
+							}
+
+							c.fillStyle = c.strokeStyle;
+							c.beginPath();
 							c.moveTo(x*size +1, y*size+1);
 							c.lineTo(x*size+ size-1, y*size+1);
 							c.lineTo(x*size+ size-1, y*size + size-1);
 							c.lineTo(x*size+1, y*size + size-1);
-							// auto return home?
+							// auto return home
+							c.stroke();
+							c.fill();
 						}
 					}
 				}
 			}
 
+			// draw the grid and border
 			function draw_grid(c) {
 				// Horizontal lines
 				for (var y = 0; y <= height_px; y += size) {
@@ -102,20 +150,24 @@
 
 			}
 
-
+			// When we've loaded, run!
 			window.onload = board_init;
 
+			// is a cell alive or dead
+			//   0 for dead, 1 for alive
+			//   walls count as dead
+			//   used by num_neighbours
 			function cell_value(x, y) {
 				//console.log('(x:' + x + ',y:' + y + ') w/s:' + (width/size) + ' h/s:' + (height/size) );
 				if (x < 0 || x >= width_c || y < 0 || y >= height_c) {
 					return 0;
 				} else {
-					return cells[y][x];
+					return cells[y][x] == 0 ? 0 : 1;
 				}
 			}
 
-
+			// return the number of neighbours for a cell
-
+			//   walls count as dead
 			function num_neighbours(x, y) {
 				var n = 0;
 				n += cell_value(x-1, y-1);
@@ -132,22 +184,24 @@
 				return n;
 			}
 
+			// Simulate one generation of cells
+			//   create a new cells 2d array and simulate the next generation
+			//   into it and then replace the current cells with it
 			function step() {
 				var new_cells = gen_cells();
 				for(var y=0; y < height_c; y++) {
 					for(var x =0 ; x < width_c; x++) {
 						var n = num_neighbours(x, y);
-						if (cells[y][x] == true) {
+						if (cells[y][x] != 0) {
 							if (n < 2 || n > 3) {
-								new_cells[y][x] = false;
+								new_cells[y][x] = 0;
 							} else {
-								console.log('ALIVE');
+								new_cells[y][x] = cells[y][x] +1;
-								new_cells[y][x] = true;
 							}
 						} else if (n == 3) {
-							new_cells[y][x] = true;
+							new_cells[y][x] = 1;
 						} else {
-							new_cells[y][x] = false;
+							new_cells[y][x] = 0;
 						}
 				 	}
 				}
@@ -155,6 +209,7 @@
 				cells = new_cells;
 			}
 
+			// Stop/Start button press
 			function control_click() {
 				var btn = document.getElementById('control-btn');
 				if (btn.value == 'Start') {
@@ -166,28 +221,83 @@
 				}
 			}
 
+			// Function to call on timmer
+			//  simulate on e generation, 
+			//  redrawn
+			//  reset timmer
 			function tick() {
 				step();
 				redraw();
-				timmer = setTimeout('tick();', 1000/hertz);
+				timmer = setTimeout('tick();', 1000.0/hertz);
 			}
 
+			// Handler for a click on the board to place/unplace a cell
 			function board_click(e) {
 				var canvas = document.getElementById('board');
 				var x = Math.floor((e.pageX-canvas.offsetLeft)/size);
 				var y = Math.floor((e.pageY-canvas.offsetTop)/size);
-				console.log(e.pageX + '/' + size + ' = ' + x + ' && ' + e.pageY + '/' + size + ' = ' +y);
 				cells[y][x] = ! cells[y][x];
 				redraw();
 			}
 
+			// Change speed handler
+			function change_speed() {
+				hertz = parseInt(document.getElementById('speed').value);
+			}
+
+			// Resize board handler (kind of not used)
+			//   Left over from experiment in resiable elastic board
+			//   Abandoned because of problems with lining up mouse clicks on board
+			//   and weird stretcing issues
+			function resize_cells() {
+				var new_cells = gen_cells();
+				var w = Math.min(width_c, cells[0].length);
+				var h = Math.min(height_c, cells.length);
+				for(var y = 0; y < h; y++) {
+					for(x = 0; x < w; x++) {
+						new_cells[y][x] = cells[y][x];
+					}
+				}
+
+				cells = new_cells;
+			}
+			
+			// What to do on a document resize (more usefull for elastic boards)
+			function canvas_resize() {
+				get_demensions();
+				resize_cells();
+				redraw();
+			}
 
 		</script>
 	</head>
-	<body>
+	<body onResize="canvas_resize();">
-		<input type="button" id="control-btn" onClick="control_click(); return false;" />
+		Speed: <select id="speed" onChange="change_speed();"> 
+			<option value="1">1 Hz</option>
+			<option value="2">2 Hz</option>
+			<option value="4">4 Hz</option>
+			<option value="8">8 Hz</option>
+			<option value="16">16 Hz</option>
+			<option value="32">32 Hz</option>
+			<option value="64">64 Hz</option>
+		</select>
+		Density: <select id="density" onChange="canvas_resize();">
+				<option value="3">X-Small</option>
+				<option value="5">Small</option>
+				<option value="10">Medium</option>
+				<option value="15">Large</option>
+				<option value="20">X-Large</option>
+			</select>
+			Effects: <select id="effects" onChange="effects=parseInt(this.value); redraw();">
+				<option value="0">None (black and white)</option>
+				<option value="1">Color age (Raindbow)</option>
+			</select>
+			<input type="button" id="control-btn" onClick="control_click(); return false;" />
+
+			<small style="margin-left:20px">Dan Ballard (2011) &lt;<a href="mailto:dan@mindstab.net">dan@mindstab.net</a>&gt;</small>
+			<input style="left:775px; position: absolute; /* width:100% height: 100%; */" type="button" value="Clear" onClick="cells = gen_cells(); redraw();" />
 		<br/>
-		<canvas width="800" height="400" id="board" onClick="board_click(event);"></canvas>
+		<canvas id="board" onClick="board_click(event);" width="800" height="400"></canvas>
 	</body>
 </html>