adding game_of_life sample

dart/samples/webcomponents/game_of_life/game_of_life.dart

+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+#library('game_of_life');
+
+#import('dart:html');
+#import('dart:isolate');
+#import('dart:math', prefix: 'Math');
+#import('package:dart-web-components/webcomponents.dart');
+
+#source('components/components.dart');
+
+typedef void Ping();
+
+/** How should the (square) board be? Measured in cells/side. */
+int GAME_SIZE = 40;
+
+/** How many pixels long is the side of a cell? (Note: must match the CSS!) */
+int CELL_SIZE = 20;
+
+/** How many pixels from the game should the control panel be? */
+int PANEL_OFFSET = 20;
+
+/** How many milliseconds between steps? */
+int STEP_TIME = 100;

[Siggi Cherem (dart-lang), 2012/09/05 20:53:03]

btw... we'll probably want to be able to set this for benchmarking later on
(e.g. do time = 0) so that we don't hide performance overhead behind this delay.

[samhop, 2012/09/07 21:41:30]

Done.

+
+/** Singletons */
+CellCoordinator get COORDINATOR {
+  if (CellCoordinator._ONLY == null) {
+    CellCoordinator._ONLY = new CellCoordinator._internal();
+  }
+  return CellCoordinator._ONLY;
+}
+
+void main() {
+  _componentsSetup();
+
+  // TODO(samhop): fix webcomponents.dart so that attributes are preserved.
+  query('div').id = 'panel';
+
+  COORDINATOR.populate();
+}
+
+void _componentsSetup() {
+  Map<String, Function> map = {
+    'x-cell' : () => new Cell.component(),
+    'x-control-panel' : () => new ControlPanel.component()
+  };
+  initializeComponents((String name) => map[name], true);
+}
+
+class CellCoordinator {

[Siggi Cherem (dart-lang), 2012/09/05 20:53:03]

+dartdoc

[samhop, 2012/09/07 21:41:30]

Done.

+  CellEvents on;
+  Timer timer;
+  int lastRefresh;
+  bool _stop;
+  StyleElement computedStyles;
+
+  void stop() {
+    _stop = true;
+  }
+
+  CellCoordinator._internal() 
+    : on = new CellCoordinatorEvents(),
+      lastRefresh = 0;
+
+  void increment(int time) {
+    // TODO(samhop): factor this functionality out so that we can benchmark it
+    // running as fast as possible
+    if (new Date.now().millisecondsSinceEpoch - lastRefresh > 100) {
+      on.step.forEach((f) => f());
+      on.resolve.forEach((f) => f());
+      lastRefresh = new Date.now().millisecondsSinceEpoch;
+    }
+    if (!_stop) {
+       window.requestAnimationFrame(increment);
+    }
+  }
+
+  void run() {
+    _stop = false;
+    window.requestAnimationFrame(increment);
+  }
+
+  void step() {
+    _stop = true;
+    increment(null);
+  }
+
+  void populate() {
+    // set up position styles
+    computedStyles = new StyleElement();
+    document.body.nodes.add(computedStyles);
+    var positionStyles = '';
+    _forEachCell((i, j) => 
+        positionStyles = _addPositionId(positionStyles, i, j));
+    computedStyles.innerHTML = positionStyles;
+
+    // add cells
+    _forEachCell((i, j) {
+      var cell = new Cell();
+      cell.coordinator = this;
+      cell.id = 'x${i}y${j}';
+      document.body.nodes.add(cell);
+    });
+
+    // position the control panel
+    var panelStyle = 
+        '''
+        #panel {
+          top: ${CELL_SIZE * GAME_SIZE + PANEL_OFFSET}px;
+          left: ${PANEL_OFFSET}px;
+        }
+        ''';
+    computedStyles.innerHTML = '${computedStyles.innerHTML}\n$panelStyle';

[Siggi Cherem (dart-lang), 2012/09/05 20:53:03]

yikes!
would some other operation work here? nodes.add?

if not, we should at least compute the full string first (e.g. use a string
buffer) and set innerHTML only once at the end? (or even create the styleelement
with the body after we have the contents)

[samhop, 2012/09/07 21:41:30]

Done.

+    
+    print(computedStyles.innerHTML);
+    
+
+    // TODO(samhop) fix webcomponents.dart so we don't have to do this
+    queryAll('.cell').forEach((cell) => cell.bound());
+  }
+
+  static _forEachCell(f) {
+    for (var i = 0; i < GAME_SIZE; i++) {
+      for (var j = 0; j < GAME_SIZE; j++) {
+        f(i, j);
+      }
+    }
+  }
+  
+  // Singleton -- there is only one CellCoordinator
+  static CellCoordinator _ONLY;
+
+  static String _addPositionId(curr, i, j) =>
+      '''
+      $curr
+      #x${i}y${j} {
+        left: ${CELL_SIZE * i}px;
+        top: ${CELL_SIZE * j}px;
+      }
+      ''';
+}
+
+class CellCoordinatorEvents implements Events {
+  List<Ping> _step_list;
+  List<Ping> _resolve_list;
+
+  CellCoordinatorEvents() 
+      : _step_list = <Ping>[],
+        _resolve_list = <Ping>[];
+
+  List<Ping> get step => _step_list;
+  List<Ping> get resolve => _resolve_list;
+}