anchor.diff:      Size,
       ValueChanged;
   
  +
  +// PAINTING NODES
  +
  +class Opacity extends OneChildRenderObjectWidget {
  +  Opacity({ Key key, this.opacity, Widget child })
  +    : super(key: key, child: child) {
  +    assert(opacity >= 0.0 && opacity <= 1.0);
  +  }
  +
  +  final double opacity;
  +
  +  RenderOpacity createRenderObject() => new RenderOpacity(opacity: opacity);
  +
  +  void updateRenderObject(RenderOpacity renderObject) {
  +    renderObject.opacity = opacity;
  +  }
  +}
  +
  +class ColorFilter extends OneChildRenderObjectWidget {
  +  ColorFilter({ Key key, this.color, this.transferMode, Widget child })
  +    : super(key: key, child: child) {
  +    assert(color != null);
  +    assert(transferMode != null);
  +  }
  +
  +  final Color color;
  +  final sky.TransferMode transferMode;
  +
  +  RenderColorFilter createRenderObject() => new RenderColorFilter(color: color, transferMode: transferMode);
  +
  +  void updateRenderObject(RenderColorFilter renderObject) {
  +    renderObject.color = color;
  +    renderObject.transferMode = transferMode;
  +  }
  +}
  +
   class DecoratedBox extends OneChildRenderObjectWidget {
     DecoratedBox({
       Key key,
  
positive.code:   final BoxDecoration decoration;
    final BoxDecorationPosition position;
  
    RenderObject createRenderObject() => new RenderDecoratedBox(
      decoration: decoration,
      position: position
    );
  
    void updateRenderObject(RenderDecoratedBox renderObject) {
      renderObject.decoration = decoration;
      renderObject.position = position;
    }
  }
  
negative.code: // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  import 'dart:sky' as sky;
  
  import 'package:sky/rendering.dart';
  import 'package:sky/services.dart';
  import 'package:sky/src/fn3/framework.dart';
  
  export 'package:sky/rendering.dart' show
  