Unify implementations of stroking radius calculations

src/core/SkStrokeRec.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 "SkStrokeRec.h"
 #include "SkPaintDefaults.h"
 
@@ skipping 116 matching lines @@
         paint->setStyle(SkPaint::kFill_Style);
         return;
     }
 
     paint->setStyle(fStrokeAndFill ? SkPaint::kStrokeAndFill_Style : SkPaint::kStroke_Style);
     paint->setStrokeWidth(fWidth);
     paint->setStrokeMiter(fMiterLimit);
     paint->setStrokeCap((SkPaint::Cap)fCap);
     paint->setStrokeJoin((SkPaint::Join)fJoin);
 }
+
+static inline SkScalar get_inflation_bounds(SkPaint::Join join,
+                                            SkScalar strokeWidth,
+                                            SkScalar miterLimit) {
+    if (strokeWidth < 0) {  // fill
+        return 0;
+    } else if (0 == strokeWidth) {
+        return SK_Scalar1;
+    }
+    // since we're stroked, outset the rect by the radius (and join type)
+    SkScalar radius = SkScalarHalf(strokeWidth);
+    if (SkPaint::kMiter_Join == join) {
+        if (miterLimit > SK_Scalar1) {
+            radius = SkScalarMul(miterLimit, radius);
+        }
+    }
+    return radius;
+}
+
+SkScalar SkStrokeRec::getInflationRadius() const {
+    return get_inflation_bounds((SkPaint::Join)fJoin, fWidth, fMiterLimit);
+}
+
+SkScalar SkStrokeRec::GetInflationRadius(const SkPaint& paint, SkPaint::Style style) {
+    SkScalar width = SkPaint::kFill_Style == style ? -SK_Scalar1 : paint.getStrokeWidth();
+    return get_inflation_bounds(paint.getStrokeJoin(), width, paint.getStrokeMiter());
+
+}