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src/core/SkPath.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBuffer.h"
 #include "SkCubicClipper.h"
 #include "SkErrorInternals.h"
@@ skipping 2747 matching lines @@
         return y1 <= y2;
     } else {
         return y1 >= y2;
     }
 }
 
 static int winding_conic(const SkPoint pts[], SkScalar x, SkScalar y, SkScalar weight,
                          int* onCurveCount) {
     SkConic conic(pts, weight);
     SkConic chopped[2];
+    // If the data points are very large, the conic may not be monotonic but may also
+    // fail to chop. Then, the chopper does not split the original conic in two.
     bool isMono = is_mono_quad(pts[0].fY, pts[1].fY, pts[2].fY) || !conic.chopAtYExtrema(chopped);
     int w = winding_mono_conic(isMono ? conic : chopped[0], x, y, onCurveCount);
     if (!isMono) {
         w += winding_mono_conic(chopped[1], x, y, onCurveCount);
     }
     return w;
 }
 
 static int winding_mono_quad(const SkPoint pts[], SkScalar x, SkScalar y, int* onCurveCount) {
     SkScalar y0 = pts[0].fY;
@@ skipping 307 matching lines @@
         }
     } while (!done);
     return SkToBool(tangents.count()) ^ isInverse;
 }
 
 int SkPath::ConvertConicToQuads(const SkPoint& p0, const SkPoint& p1, const SkPoint& p2,
                                 SkScalar w, SkPoint pts[], int pow2) {
     const SkConic conic(p0, p1, p2, w);
     return conic.chopIntoQuadsPOW2(pts, pow2);
 }