fix some pathops bugs found in 1M skps

src/pathops/SkOpAngle.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 "SkOpAngle.h"
 #include "SkOpSegment.h"
 #include "SkPathOpsCurve.h"
 #include "SkTSort.h"
@@ skipping 204 matching lines @@
     return -1;
 }
 
 bool SkOpAngle::checkCrossesZero() const {
     int start = SkTMin(fSectorStart, fSectorEnd);
     int end = SkTMax(fSectorStart, fSectorEnd);
     bool crossesZero = end - start > 16;
     return crossesZero;
 }
 
-// loop looking for a pair of angle parts that are too close to be sorted
-/* This is called after other more simple intersection and angle sorting tests have been exhausted.
-   This should be rarely called -- the test below is thorough and time consuming.
-   This checks the distance between start points; the distance between 
-*/
-void SkOpAngle::checkNearCoincidence() {
-    SkOpAngle* test = this;
-    do {
-        SkOpSegment* testSegment = test->segment();
-        double testStartT = test->start()->t();
-        SkDPoint testStartPt = testSegment->dPtAtT(testStartT);
-        double testEndT = test->end()->t();
-        SkDPoint testEndPt = testSegment->dPtAtT(testEndT);
-        double testLenSq = testStartPt.distanceSquared(testEndPt);
-        if (0) {
-            SkDebugf("%s testLenSq=%1.9g id=%d\n", __FUNCTION__, testLenSq, testSegment->debugID());
-        }
-        double testMidT = (testStartT + testEndT) / 2;
-        SkOpAngle* next = test;
-        while ((next = next->fNext) != this) {
-            SkOpSegment* nextSegment = next->segment();
-            double testMidDistSq = testSegment->distSq(testMidT, next);
-            double testEndDistSq = testSegment->distSq(testEndT, next);
-            double nextStartT = next->start()->t();
-            SkDPoint nextStartPt = nextSegment->dPtAtT(nextStartT);
-            double distSq = testStartPt.distanceSquared(nextStartPt);
-            double nextEndT = next->end()->t();
-            double nextMidT = (nextStartT + nextEndT) / 2;
-            double nextMidDistSq = nextSegment->distSq(nextMidT, test);
-            double nextEndDistSq = nextSegment->distSq(nextEndT, test);
-            if (0) {
-                SkDebugf("%s distSq=%1.9g testId=%d nextId=%d\n", __FUNCTION__, distSq,
-                        testSegment->debugID(), nextSegment->debugID());
-                SkDebugf("%s testMidDistSq=%1.9g\n", __FUNCTION__, testMidDistSq);
-                SkDebugf("%s testEndDistSq=%1.9g\n", __FUNCTION__, testEndDistSq);
-                SkDebugf("%s nextMidDistSq=%1.9g\n", __FUNCTION__, nextMidDistSq);
-                SkDebugf("%s nextEndDistSq=%1.9g\n", __FUNCTION__, nextEndDistSq);
-                SkDPoint nextEndPt = nextSegment->dPtAtT(nextEndT);
-                double nextLenSq = nextStartPt.distanceSquared(nextEndPt);
-                SkDebugf("%s nextLenSq=%1.9g\n", __FUNCTION__, nextLenSq);
-                SkDebugf("\n");
-            }
-        }
-        test = test->fNext;
-    } while (test->fNext != this); 
-}
-
 bool SkOpAngle::checkParallel(SkOpAngle* rh) {
     SkDVector scratch[2];
     const SkDVector* sweep, * tweep;
     if (!this->fUnorderedSweep) {
         sweep = this->fSweep;
     } else {
         scratch[0] = this->fCurvePart[1] - this->fCurvePart[0];
         sweep = &scratch[0];
     }
     if (!rh->fUnorderedSweep) {
@@ skipping 809 matching lines @@
         return true;
     }
     SkASSERT(s0dt0 != 0);
     double m = s0xt0 / s0dt0;
     double sDist = sweep[0].length() * m;
     double tDist = tweep[0].length() * m;
     bool useS = fabs(sDist) < fabs(tDist);
     double mFactor = fabs(useS ? this->distEndRatio(sDist) : rh->distEndRatio(tDist));
     return mFactor < 2400;  // empirically found limit
 }