Attempt to throw away rrect clips of rrects.

include/core/SkRRect.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkRRect_DEFINED
 #define SkRRect_DEFINED
 
@@ skipping 29 matching lines @@
     setRectRadii, etc.)
 
     This class is intended to roughly match CSS' border-*-*-radius capabilities.
     This means:
         If either of a corner's radii are 0 the corner will be square.
         Negative radii are not allowed (they are clamped to zero).
         If the corner curves overlap they will be proportionally reduced to fit.
 */
 class SK_API SkRRect {
 public:
+    SkRRect() { /* unititialized */ }
+    SkRRect(const SkRRect&) = default;
+    SkRRect& operator=(const SkRRect&) = default;
+
     /**
      * Enum to capture the various possible subtypes of RR. Accessed
      * by type(). The subtypes become progressively less restrictive.
      */
     enum Type {
         // !< The RR is empty
         kEmpty_Type,
 
         //!< The RR is actually a (non-empty) rect (i.e., at least one radius
         //!< at each corner is zero)
@@ skipping 207 matching lines @@
         this->inset(-dx, -dy, this);
     }
 
     /**
      * Translate the rrect by (dx, dy).
      */
     void offset(SkScalar dx, SkScalar dy) {
         fRect.offset(dx, dy);
     }
 
+    SkRRect SK_WARN_UNUSED_RESULT makeOffset(SkScalar dx, SkScalar dy) const {
+        return SkRRect(fRect.makeOffset(dx, dy), fRadii, fType);
+    }
+
     /**
      *  Returns true if 'rect' is wholy inside the RR, and both
      *  are not empty.
      */
     bool contains(const SkRect& rect) const;
 
     SkDEBUGCODE(void validate() const;)
 
     enum {
         kSizeInMemory = 12 * sizeof(SkScalar)
@@ skipping 28 matching lines @@
      *      which would make this function no longer const.
      *  @return true on success, false on failure. If false, dst is unmodified.
      */
     bool transform(const SkMatrix& matrix, SkRRect* dst) const;
 
     void dump(bool asHex) const;
     void dump() const { this->dump(false); }
     void dumpHex() const { this->dump(true); }
 
 private:
+    SkRRect(const SkRect& rect, const SkVector radii[4], int32_t type)
+        : fRect(rect)
+        , fRadii{radii[0], radii[1], radii[2], radii[3]}
+        , fType(type) {}
+
     SkRect fRect;
     // Radii order is UL, UR, LR, LL. Use Corner enum to index into fRadii[]
     SkVector fRadii[4];
     // use an explicitly sized type so we're sure the class is dense (no uninitialized bytes)
     int32_t fType;
     // TODO: add padding so we can use memcpy for flattening and not copy
     // uninitialized data
 
     void computeType();
     bool checkCornerContainment(SkScalar x, SkScalar y) const;
     void scaleRadii();
 
     // to access fRadii directly
     friend class SkPath;
 };
 
 #endif