add new onClip* methods to SkCanvas

include/core/SkCanvas.h

Index: include/core/SkCanvas.h
===================================================================
--- include/core/SkCanvas.h	(revision 13577)
+++ include/core/SkCanvas.h	(working copy)
@@ -448,10 +448,9 @@
         specified region. This does not intersect or in any other way account
         for the existing clip region.
         @param deviceRgn The region to copy into the current clip.
-        @return true if the new clip region is non-empty
     */
-    bool setClipRegion(const SkRegion& deviceRgn) {
-        return this->clipRegion(deviceRgn, SkRegion::kReplace_Op);
+    void setClipRegion(const SkRegion& deviceRgn) {
+        this->clipRegion(deviceRgn, SkRegion::kReplace_Op);
     }
 
     /** Return true if the specified rectangle, after being transformed by the
@@ -979,7 +978,7 @@
      *  result, subsequent calls will be cheap (until the clip state changes,
      *  which can happen on any clip..() or restore() call.
      */
-    bool isClipEmpty() const;
+    virtual bool isClipEmpty() const;

[reed1, 2014/02/27 18:43:50]

Why does this need to be virtual, but not (also) getClipType()?

[robertphillips, 2014/02/27 20:20:30]

I learned about a new canvas entry point today. Please see new patch.

 
     /** Return the current matrix on the canvas.
         This does not account for the translate in any of the devices.
@@ -1078,6 +1077,16 @@
 
     virtual void onDrawDRRect(const SkRRect&, const SkRRect&, const SkPaint&);
 
+    enum ClipEdgeStyle {
+        kHard_ClipEdgeStyle,
+        kSoft_ClipEdgeStyle
+    };
+
+    virtual void onClipRect(const SkRect& rect, SkRegion::Op op, ClipEdgeStyle edgeStyle);
+    virtual void onClipRRect(const SkRRect& rrect, SkRegion::Op op, ClipEdgeStyle edgeStyle);
+    virtual void onClipPath(const SkPath& path, SkRegion::Op op, ClipEdgeStyle edgeStyle);
+    virtual void onClipRegion(const SkRegion& deviceRgn, SkRegion::Op op);
+
     // Returns the canvas to be used by DrawIter. Default implementation
     // returns this. Subclasses that encapsulate an indirect canvas may
     // need to overload this method. The impl must keep track of this, as it
@@ -1094,7 +1103,7 @@
 
     // Called by child classes that override clipPath and clipRRect to only
     // track fast conservative clip bounds, rather than exact clips.
-    bool updateClipConservativelyUsingBounds(const SkRect&, SkRegion::Op,
+    void updateClipConservativelyUsingBounds(const SkRect&, SkRegion::Op,
                                              bool inverseFilled);
 
     // notify our surface (if we have one) that we are about to draw, so it