allow conic chop to fail

samplecode/SampleAAGeometry.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SampleCode.h"
 #include "SkCanvas.h"
 #include "SkGeometry.h"
@@ skipping 202 matching lines @@
                 case SkPath::kQuad_Verb: {
                     SkPoint chop[5];
                     SkChopQuadAtHalf(pts, chop);
                     result.quadTo(chop[1], chop[2]);
                     pts[1] = chop[3];
                     } break;
                 case SkPath::kConic_Verb: {
                     SkConic chop[2];
                     SkConic conic;
                     conic.set(pts, iter.conicWeight());
-                    conic.chopAt(0.5f, chop);
+                    if (!conic.chopAt(0.5f, chop)) {
+                        return;
+                    }
                     result.conicTo(chop[0].fPts[1], chop[0].fPts[2], chop[0].fW);
                     pts[1] = chop[1].fPts[1];
                     weight = chop[1].fW;
                     } break;
                 case SkPath::kCubic_Verb: {
                     SkPoint chop[7];
                     SkChopCubicAtHalf(pts, chop);
                     result.cubicTo(chop[1], chop[2], chop[3]);
                     pts[1] = chop[4];
                     pts[2] = chop[5];
@@ skipping 1119 matching lines @@
 
     void conic_coverage(SkPoint pts[3], SkScalar weight, uint8_t* distanceMap, int w, int h) {
         SkScalar dist = pts[0].Distance(pts[0], pts[2]);
         if (dist < gCurveDistance) {
             (void) coverage(pts[0], pts[2], distanceMap, w, h);
             return;
         }
         SkConic split[2];
         SkConic conic;
         conic.set(pts, weight);
-        conic.chopAt(0.5f, split);
-        conic_coverage(split[0].fPts, split[0].fW, distanceMap, w, h);
-        conic_coverage(split[1].fPts, split[1].fW, distanceMap, w, h);
+        if (conic.chopAt(0.5f, split)) {
+            conic_coverage(split[0].fPts, split[0].fW, distanceMap, w, h);
+            conic_coverage(split[1].fPts, split[1].fW, distanceMap, w, h);
+        }
     }
 
     void cubic_coverage(SkPoint pts[4], uint8_t* distanceMap, int w, int h) {
         SkScalar dist = pts[0].Distance(pts[0], pts[3]);
         if (dist < gCurveDistance) {
             (void) coverage(pts[0], pts[3], distanceMap, w, h);
             return;
         }
         SkPoint split[7];
         SkChopCubicAt(pts, split, 0.5f);
@@ skipping 484 matching lines @@
                     (void) this->onClick(&click);
                     return true;
                 }
             }
         }
     }
     return this->INHERITED::onQuery(evt);
 }
     
 DEF_SAMPLE( return new AAGeometryView; )