Add antiAlias and saveCount to clipPath and restore (#5638)

liyuqian · web-flow · commit a2bf80590b80 · 2018-06-29T16:24:12.000-07:00
This would enable us to solve flutter/flutter#18057
diff --git a/lib/ui/painting.dart b/lib/ui/painting.dart
@@ -2886,6 +2886,15 @@ class Canvas extends NativeFieldWrapperClass2 {
   /// cause the new layer to be composited into the previous layer.
   void restore() native 'Canvas_restore';
 
+  /// Restore the current save stack to the state where [saveCount] is gotten.
+  ///
+  /// Use [save] and [saveLayer] to push state onto the stack, and use
+  /// [getSaveCount] to get the [saveCount].
+  ///
+  /// If a state was pushed with with [saveLayer], then this call will also
+  /// cause the new layer to be composited into the previous layer.
+  void restoreToCount(int saveCount) native 'Canvas_restoreToCount';
+
   /// Returns the number of items on the save stack, including the
   /// initial state. This means it returns 1 for a clean canvas, and
   /// that each call to [save] and [saveLayer] increments it, and that
@@ -2956,11 +2965,11 @@ class Canvas extends NativeFieldWrapperClass2 {
   /// multiple draw commands intersect with the clip boundary, this can result
   /// in incorrect blending at the clip boundary. See [saveLayer] for a
   /// discussion of how to address that and some examples of using [clipRRect].
-  void clipRRect(RRect rrect) {
+  void clipRRect(RRect rrect, [bool doAntiAlias = true]) {
     assert(_rrectIsValid(rrect));
-    _clipRRect(rrect._value);
+    _clipRRect(rrect._value, doAntiAlias);
   }
-  void _clipRRect(Float32List rrect) native 'Canvas_clipRRect';
+  void _clipRRect(Float32List rrect, bool doAntiAlias) native 'Canvas_clipRRect';
 
   /// Reduces the clip region to the intersection of the current clip and the
   /// given [Path].
@@ -2969,11 +2978,11 @@ class Canvas extends NativeFieldWrapperClass2 {
   /// multiple draw commands intersect with the clip boundary, this can result
   /// in incorrect blending at the clip boundary. See [saveLayer] for a
   /// discussion of how to address that.
-  void clipPath(Path path) {
+  void clipPath(Path path, [bool doAntiAlias = true]) {
     assert(path != null); // path is checked on the engine side
-    _clipPath(path);
+    _clipPath(path, doAntiAlias);
   }
-  void _clipPath(Path path) native 'Canvas_clipPath';
+  void _clipPath(Path path, bool doAntiAlias) native 'Canvas_clipPath';
 
   /// Paints the given [Color] onto the canvas, applying the given
   /// [BlendMode], with the given color being the source and the background
diff --git a/lib/ui/painting/canvas.cc b/lib/ui/painting/canvas.cc
@@ -35,6 +35,7 @@ IMPLEMENT_WRAPPERTYPEINFO(ui, Canvas);
   V(Canvas, saveLayerWithoutBounds) \
   V(Canvas, saveLayer)              \
   V(Canvas, restore)                \
+  V(Canvas, restoreToCount)         \
   V(Canvas, getSaveCount)           \
   V(Canvas, translate)              \
   V(Canvas, scale)                  \
@@ -120,6 +121,12 @@ void Canvas::restore() {
   canvas_->restore();
 }
 
+void Canvas::restoreToCount(int saveCount) {
+  if (!canvas_)
+    return;
+  canvas_->restoreToCount(saveCount);
+}
+
 int Canvas::getSaveCount() {
   if (!canvas_)
     return 0;
@@ -166,19 +173,19 @@ void Canvas::clipRect(double left,
   canvas_->clipRect(SkRect::MakeLTRB(left, top, right, bottom), clipOp, true);
 }
 
-void Canvas::clipRRect(const RRect& rrect) {
+void Canvas::clipRRect(const RRect& rrect, bool doAntiAlias) {
   if (!canvas_)
     return;
-  canvas_->clipRRect(rrect.sk_rrect, true);
+  canvas_->clipRRect(rrect.sk_rrect, doAntiAlias);
 }
 
-void Canvas::clipPath(const CanvasPath* path) {
+void Canvas::clipPath(const CanvasPath* path, bool doAntiAlias) {
   if (!canvas_)
     return;
   if (!path)
     Dart_ThrowException(
         ToDart("Canvas.clipPath called with non-genuine Path."));
-  canvas_->clipPath(path->path(), true);
+  canvas_->clipPath(path->path(), doAntiAlias);
 }
 
 void Canvas::drawColor(SkColor color, SkBlendMode blend_mode) {
diff --git a/lib/ui/painting/canvas.h b/lib/ui/painting/canvas.h
@@ -48,6 +48,7 @@ class Canvas : public fxl::RefCountedThreadSafe<Canvas>,
                  const Paint& paint,
                  const PaintData& paint_data);
   void restore();
+  void restoreToCount(int saveCount);
   int getSaveCount();
 
   void translate(double dx, double dy);
@@ -61,8 +62,8 @@ class Canvas : public fxl::RefCountedThreadSafe<Canvas>,
                 double right,
                 double bottom,
                 SkClipOp clipOp);
-  void clipRRect(const RRect& rrect);
-  void clipPath(const CanvasPath* path);
+  void clipRRect(const RRect& rrect, bool doAntiAlias = true);
+  void clipPath(const CanvasPath* path, bool doAntiAlias = true);
 
   void drawColor(SkColor color, SkBlendMode blend_mode);
   void drawLine(double x1,
