pathops: Cosmetic only change, update comments around ComplexBreak().

src/pathops/SkOpEdgeBuilder.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 "SkGeometry.h"
 #include "SkOpEdgeBuilder.h"
 #include "SkReduceOrder.h"
 
@@ skipping 181 matching lines @@
             case SkPath::kLine_Verb:
                 fCurrentContour->addLine(pointsPtr, fAllocator);
                 break;
             case SkPath::kQuad_Verb:
                 fCurrentContour->addQuad(pointsPtr, fAllocator);
                 break;
             case SkPath::kConic_Verb:
                 fCurrentContour->addConic(pointsPtr, *weightPtr++, fAllocator);
                 break;
             case SkPath::kCubic_Verb: {
-                // split self-intersecting cubics in two before proceeding
-                // if the cubic is convex, it doesn't self intersect.
-                SkScalar loopT;
-                if (SkDCubic::ComplexBreak(pointsPtr, &loopT)) {
-                    SkPoint cubicPair[7]; 
-                    SkChopCubicAt(pointsPtr, cubicPair, loopT);
+                // Split complex cubics (such as self-intersecting curves or
+                // ones with difficult curvature) in two before proceeding.
+                // This can be required for intersection to succeed.
+                SkScalar splitT;
+                if (SkDCubic::ComplexBreak(pointsPtr, &splitT)) {
+                    SkPoint cubicPair[7];
+                    SkChopCubicAt(pointsPtr, cubicPair, splitT);
                     if (!SkScalarsAreFinite(&cubicPair[0].fX, SK_ARRAY_COUNT(cubicPair) * 2)) {
                         return false;
                     }
                     SkPoint cStorage[2][4];
                     SkPath::Verb v1 = SkReduceOrder::Cubic(&cubicPair[0], cStorage[0]);
                     SkPath::Verb v2 = SkReduceOrder::Cubic(&cubicPair[3], cStorage[1]);
                     if (v1 != SkPath::kMove_Verb && v2 != SkPath::kMove_Verb) {
                         SkPoint* curve1 = v1 == SkPath::kCubic_Verb ? &cubicPair[0] : cStorage[0];
                         SkPoint* curve2 = v2 == SkPath::kCubic_Verb ? &cubicPair[3] : cStorage[1];
                         for (int index = 0; index < SkPathOpsVerbToPoints(v1); ++index) {
@@ skipping 23 matching lines @@
         }
         SkASSERT(fCurrentContour);
         fCurrentContour->debugValidate();
         pointsPtr += SkPathOpsVerbToPoints(verb);
     }
    if (fCurrentContour && fCurrentContour->count() &&!fAllowOpenContours && !close()) {
        return false;
    }
    return true;
 }