Add LinearBoxGradient and RadialBoxGradient decorations for RenderDecoratedBox.

sky/sdk/lib/framework/rendering/box.dart

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 import 'dart:math' as math;
 import 'dart:sky' as sky;
 import 'dart:typed_data';
 import 'object.dart';
 import '../painting/shadows.dart';
 import 'package:vector_math/vector_math.dart';
@@ skipping 637 matching lines @@
     this.blur
   });
 
   final Color color;
   final Size offset;
   final double blur;
 
   String toString() => 'BoxShadow($color, $offset, $blur)';
 }
 
+abstract class BoxGradient {
+  String toString();

[abarth-chromium, 2015/06/09 21:23:39]

You can skip this declaration.  It's declared already on dart's root object
type.

[Matt Perry, 2015/06/09 21:38:28]

Done.

+  sky.Shader createShader();
+}
+
+class LinearBoxGradient extends BoxGradient {
+  LinearBoxGradient({
+    this.endPoints,
+    this.colors,
+    this.colorStops,
+    this.tileMode: sky.TileMode.clamp
+  });
+
+  String toString() =>
+      'LinearBoxGradient($endPoints, $colors, $colorStops, $tileMode)';
+
+  sky.Shader createShader() {
+    return new sky.Gradient.Linear(this.endPoints, this.colors, this.colorStops,
+                                   this.tileMode);
+  }
+
+  final List<Point> endPoints;
+  final List<Color> colors;
+  final List<double> colorStops;
+  final sky.TileMode tileMode;
+}
+
+class RadialBoxGradient extends BoxGradient {
+  RadialBoxGradient({
+    this.center,
+    this.radius,
+    this.colors,
+    this.colorStops,
+    this.tileMode: sky.TileMode.clamp
+  });
+
+  String toString() =>
+      'RadialBoxGradient($center, $radius, $colors, $colorStops, $tileMode)';
+
+  sky.Shader createShader() {
+    return new sky.Gradient.Radial(this.center, this.radius, this.colors,
+                                   this.colorStops, this.tileMode);
+  }
+
+  final Point center;
+  final double radius;
+  final List<Color> colors;
+  final List<double> colorStops;
+  final sky.TileMode tileMode;
+}
+
 // This must be immutable, because we won't notice when it changes
 class BoxDecoration {
   const BoxDecoration({
     this.backgroundColor,
     this.border,
     this.borderRadius,
-    this.boxShadow
+    this.boxShadow,
+    this.boxGradient
   });
 
   final Color backgroundColor;
   final double borderRadius;
   final Border border;
   final List<BoxShadow> boxShadow;
+  final BoxGradient boxGradient;

[abarth-chromium, 2015/06/09 21:23:40]

boxGradient -> gradient

We should probably rename boxShadow to shadow.  I just used that name to be
consistent with CSS.

[Matt Perry, 2015/06/09 21:38:28]

Done.

 
   String toString([String prefix = '']) {
     List<String> result = [];
     if (backgroundColor != null)
       result.add('${prefix}backgroundColor: $backgroundColor');
     if (border != null)
       result.add('${prefix}border: $border');
     if (borderRadius != null)
       result.add('${prefix}borderRadius: $borderRadius');
     if (boxShadow != null)
       result.add('${prefix}boxShadow: ${boxShadow.map((shadow) => shadow.toString())}');
+    if (boxGradient != null)
+      result.add('${prefix}boxGradient: $boxGradient');
     if (result.isEmpty)
       return '${prefix}<no decorations specified>';
     return result.join('\n');
   }
 }
 
 class RenderDecoratedBox extends RenderProxyBox {
 
   RenderDecoratedBox({
     BoxDecoration decoration,
@@ skipping 21 matching lines @@
       if (_decoration.backgroundColor != null)
         paint.color = _decoration.backgroundColor;
 
       if (_decoration.boxShadow != null) {
         var builder = new ShadowDrawLooperBuilder();
         for (BoxShadow boxShadow in _decoration.boxShadow)
           builder.addShadow(boxShadow.offset, boxShadow.color, boxShadow.blur);
         paint.setDrawLooper(builder.build());
       }
 
+      if (_decoration.boxGradient != null)
+        paint.setShader(_decoration.boxGradient.createShader());
+
       _cachedBackgroundPaint = paint;
     }
 
     return _cachedBackgroundPaint;
   }
 
   void paint(RenderObjectDisplayList canvas) {
     assert(size.width != null);
     assert(size.height != null);
 
-    if (_decoration.backgroundColor != null || _decoration.boxShadow != null) {
+    if (_decoration.backgroundColor != null || _decoration.boxShadow != null ||
+        _deocration.boxGradient != null) {
       Rect rect = new Rect.fromLTRB(0.0, 0.0, size.width, size.height);
       if (_decoration.borderRadius == null)
         canvas.drawRect(rect, _backgroundPaint);
       else
         canvas.drawRRect(new sky.RRect()..setRectXY(rect, _decoration.borderRadius, _decoration.borderRadius), _backgroundPaint);
     }
 
     if (_decoration.border != null) {
       assert(_decoration.borderRadius == null); // TODO(abarth): Implement borders with border radius.
 
@@ skipping 272 matching lines @@
 
   void defaultPaint(RenderObjectDisplayList canvas) {
     RenderBox child = firstChild;
     while (child != null) {
       assert(child.parentData is ParentDataType);
       canvas.paintChild(child, child.parentData.position);
       child = child.parentData.nextSibling;
     }
   }
 }