Examples - Add Grid Size Up/Down Buttons

lib/game/Game.dart

@@ -11,11 +11,11 @@ class Game {
 
   double _oscill = 0.1;
   bool _oscillDir = true; // oscillate upwards (true) or downwards (false)
-  double _OSCILLSPEED = 0.1;
+  double _OSCILLSPEED = 1.0;
   bool _fwd = true;
 
   Game(CanvasElement this.canvas) {
-    grid = _buildGrid(5, 5, new Color(255, 0, 255));
+    grid = _buildGrid(5, new Color(255, 255, 255));
   }
 
   // In-World Logic Updates
@@ -33,20 +33,27 @@ class Game {
 
     ctx.clearRect(0, 0, canvas.width, canvas.height);
     _grid_foreach((x, y) {
-        Color col = _oscillate(grid[y][x]);
+        Color col = _getOscillatedCol(grid[y][x]);
         ctx.setFillColorRgb(col.r, col.g, col.b);
         ctx.fillRect(x*brickW, y*brickH, brickW, brickH);
     });
+
+    // This should usually be place in update()
+    // Placed here to highlight render speed changes for some examples
+    // See dirty flag Loop for details
+    _oscillate();
   }
 
   // Slightly oscillating colors to highlight rendering updates
-  Color _oscillate(Color col) {
+  void _oscillate() {
     if(_oscill >= 50.0 || _oscill <= -50.0) {
       _oscillDir = !_oscillDir;
       _oscill = max( min(_oscill, 49.0), -49.0);
     }
     else _oscillDir == true ? _oscill += _OSCILLSPEED : _oscill -= _OSCILLSPEED;
+  }
 
+  Color _getOscillatedCol(Color col) {
     int o = _oscill.toInt();
     return new Color(col.r + o, col.g + o, col.b + o);
   }
@@ -59,16 +66,29 @@ class Game {
     }
   }
 
-  List<List<Color>> _buildGrid(int w, int h, Color col) {
-    List<List<Color>> grid = new List(h);
-    for (int y = 0; y < h; y++) {
-      grid[y] = new List(w);
-      for (int x = 0; x < w; x++) {
+  List<List<Color>> _buildGrid(int size, Color col) {
+    List<List<Color>> grid = new List(size);
+    for (int y = 0; y < size; y++) {
+      grid[y] = new List(size);
+      for (int x = 0; x < size; x++) {
         grid[y][x] = col;
       }
     }
     return grid;
   }
+
+  // Grid Size Button Implementation
+  // true makes squares larger
+  // false makes squares smaller
+  void changeGridSize(bool larger) {
+    if(larger) {
+      if(grid.length <= 5) return;
+      this.grid = _buildGrid(grid.length - 5, Color(255, 255, 255));
+    } else {
+      if(grid.length >= 60) return;
+      this.grid = _buildGrid(grid.length + 5, Color(255, 255, 255));
+    }
+  }
 }
 
 class Color {

web/main.dart

@@ -112,7 +112,19 @@ void addControls(Example ex) {
       ..text = "Stop"
       ..onClick.listen((e) {
         ex.loop.stop();
-      })));
+      }))
+    ..append(new ButtonElement()
+      ..text = "+"
+      ..onClick.listen((e) {
+        ex.loop.game.changeGridSize(true);
+      }))
+    ..append(new ButtonElement()
+      ..text = "-"
+      ..onClick.listen((e) {
+        ex.loop.game.changeGridSize(false);
+      }))
+  );
+
 
   // Don't add controls which don't work anyways (for simple examples)
   if(examples.indexOf(ex) <= 1) return;