Decouple Canvas from DisplayList and map Picture and PictureRecorder more directly to their Skia co…

sky/examples/game/lib/sprite.dart

 part of sprites;
 
 /// A Sprite is a [Node] that renders a bitmap image to the screen.
 class Sprite extends NodeWithSize {
 
   /// The image that the sprite will render to screen.
   ///
   /// If the image is null, the sprite will be rendered as a red square
   /// marking the bounds of the sprite.
   ///
@@ skipping 32 matching lines @@
   ///
   ///     mySprite.opacity = 0.5;
   double get opacity => _opacity;
 
   void set opacity(double opacity) {
     assert(opacity != null);
     assert(opacity >= 0.0 && opacity <= 1.0);
     _opacity = opacity;
   }
 
-  void paint(PictureRecorder canvas) {
+  void paint(RenderCanvas canvas) {
     canvas.save();
 
     // Account for pivot point
     applyTransformForPivot(canvas);
 
     if (image != null && image.width > 0 && image.height > 0) {
       
       double scaleX = size.width/image.width;
       double scaleY = size.height/image.height;
       
@@ skipping 24 matching lines @@
       canvas.drawImage(image, 0.0, 0.0, paint);
     }
     else {
       // Paint a red square for missing texture
       canvas.drawRect(new Rect.fromLTRB(0.0, 0.0, size.width, size.height),
           new Paint()..color = const Color.fromARGB(255, 255, 0, 0));
     }
     canvas.restore();
   }
 }