samples/poppopwin: upgrade to first-class sample

samples/third_party/pop-pop-win/lib/src/canvas/game_background_element.dart

Index: samples/third_party/pop-pop-win/lib/src/canvas/game_background_element.dart
diff --git a/samples/third_party/pop-pop-win/lib/src/canvas/game_background_element.dart b/samples/third_party/pop-pop-win/lib/src/canvas/game_background_element.dart
deleted file mode 100644
index e6b1fb3e9fdf39e75dfb3ab7cd978ec2fc420de4..0000000000000000000000000000000000000000
--- a/samples/third_party/pop-pop-win/lib/src/canvas/game_background_element.dart
+++ /dev/null
@@ -1,91 +0,0 @@
-part of ppw_canvas;
-
-class GameBackgroundElement extends Thing {
-  GameBackgroundElement() : super(0, 0) {
-    cacheEnabled = true;
-  }
-
-  void update() {
-    if(size != this._gameElement.size) {
-      size = this._gameElement.size;
-    }
-  }
-
-  void drawOverride(CanvasRenderingContext2D ctx) {
-    final rightBgLoc = SquareElement._size * (_gameElement._game.field.width -1) +
-        GameElement._edgeOffset;
-    final bottomBgLoc = SquareElement._size * (_gameElement._game.field.height -1) +
-        GameElement._edgeOffset;
-
-    ctx.save();
-    ctx.translate(_gameElement._scaledBoardOffset.x, _gameElement._scaledBoardOffset.y);
-
-    _textureData.drawTextureKeyAt(ctx, 'game_board_corner_top_left.png');
-
-    _textureData.drawTextureKeyAt(ctx, 'game_board_corner_top_right.png',
-        new Coordinate(rightBgLoc, 0));
-
-    _textureData.drawTextureKeyAt(ctx, 'game_board_corner_bottom_left.png',
-                     new Coordinate(0, bottomBgLoc));
-    _textureData.drawTextureKeyAt(ctx, 'game_board_corner_bottom_right.png',
-        new Coordinate(rightBgLoc, bottomBgLoc));
-
-    for(var i = 1; i < _gameElement._game.field.width - 1; i++) {
-      final xLoc = SquareElement._size * i + GameElement._edgeOffset;
-      _textureData.drawTextureKeyAt(ctx, 'game_board_side_top.png',
-          new Coordinate(xLoc, 0));
-      _textureData.drawTextureKeyAt(ctx, 'game_board_side_bottom.png',
-          new Coordinate(xLoc, bottomBgLoc));
-    }
-
-    for(var i = 1; i < _gameElement._game.field.height - 1; i++) {
-      final yLoc = SquareElement._size * i + GameElement._edgeOffset;
-      _textureData.drawTextureKeyAt(ctx, 'game_board_side_left.png',
-          new Coordinate(0, yLoc));
-      _textureData.drawTextureKeyAt(ctx, 'game_board_side_right.png',
-          new Coordinate(rightBgLoc, yLoc));
-    }
-
-    ctx.restore();
-
-    //
-    // start drawing corners
-    //
-
-    ctx.save();
-    // top left
-    ctx.transform(_gameElement._scale, 0, 0, _gameElement._scale, 0, 0);
-    _drawCorner(ctx);
-
-    // right flip
-    ctx.save();
-    ctx.transform(-1 , 0, 0, 1, GameElement._backgroundSize.width, 0);
-    _drawCorner(ctx);
-
-    // nested bottom, right flip
-    ctx.transform(1 , 0, 0, -1, 0, GameElement._backgroundSize.height);
-    _drawCorner(ctx);
-
-    ctx.restore();
-
-    // bottom left
-    ctx.transform(1 , 0, 0, -1, 0, GameElement._backgroundSize.height);
-    _drawCorner(ctx);
-
-    ctx.restore();
-
-    //
-    // end drawing corners
-    //
-  }
-
-  void _drawCorner(CanvasRenderingContext2D ctx) {
-    _textureData.drawTextureKeyAt(ctx, 'background_top_left.png');
-    _textureData.drawTextureKeyAt(ctx, 'background_side_left.png',
-        new Coordinate(0, GameElement._boardOffset.y));
-  }
-
-  GameElement get _gameElement => (parent as CanvasThing).parent;
-
-  TextureData get _textureData => _gameElement._textureData;
-}