plumbing for GPU fast blur

src/core/SkRRect.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkRRect.h"
 #include "SkMatrix.h"
 
@@ skipping 154 matching lines @@
     //      x^2     y^2
     //     ----- + ----- <= 1
     //      a^2     b^2
     // or :
     //     b^2*x^2 + a^2*y^2 <= (ab)^2
     SkScalar dist =  SkScalarMul(SkScalarSquare(canonicalPt.fX), SkScalarSquare(fRadii[index].fY)) +
                      SkScalarMul(SkScalarSquare(canonicalPt.fY), SkScalarSquare(fRadii[index].fX));
     return dist <= SkScalarSquare(SkScalarMul(fRadii[index].fX, fRadii[index].fY));
 }
 
+bool SkRRect::allCornersCircular() const {
+    return fRadii[0].fX == fRadii[0].fY &&
+        fRadii[1].fX == fRadii[1].fY &&
+        fRadii[2].fX == fRadii[2].fY &&
+        fRadii[3].fX == fRadii[3].fY;
+}
+
 bool SkRRect::contains(const SkRect& rect) const {
     if (!this->getBounds().contains(rect)) {
         // If 'rect' isn't contained by the RR's bounds then the
         // RR definitely doesn't contain it
         return false;
     }
 
     if (this->isRect()) {
         // the prior test was sufficient
         return true;
@@ skipping 230 matching lines @@
             SkASSERT(!allRadiiZero && !allRadiiSame && !allCornersSquare);
             break;
         case kUnknown_Type:
             // no limits on this
             break;
     }
 }
 #endif // SK_DEBUG
 
 ///////////////////////////////////////////////////////////////////////////////