update pathops to circle sort

src/pathops/SkDQuadIntersection.cpp

 // Another approach is to start with the implicit form of one curve and solve
 // (seek implicit coefficients in QuadraticParameter.cpp
 // by substituting in the parametric form of the other.
 // The downside of this approach is that early rejects are difficult to come by.
 // http://planetmath.org/encyclopedia/GaloisTheoreticDerivationOfTheQuarticFormula.html#step
 
-
 #include "SkDQuadImplicit.h"
 #include "SkIntersections.h"
 #include "SkPathOpsLine.h"
 #include "SkQuarticRoot.h"
 #include "SkTArray.h"
 #include "SkTSort.h"
 
 /* given the implicit form 0 = Ax^2 + Bxy + Cy^2 + Dx + Ey + F
  * and given x = at^2 + bt + c  (the parameterized form)
  *           y = dt^2 + et + f
@@ skipping 134 matching lines @@
     SkDLine line = {{hull[2], hull[0]}};
     const SkDLine* testLines[] = { &line, (const SkDLine*) &hull[0], (const SkDLine*) &hull[1] };
     const size_t kTestCount = SK_ARRAY_COUNT(testLines);
     SkSTArray<kTestCount * 2, double, true> tsFound;
     for (size_t index = 0; index < kTestCount; ++index) {
         SkIntersections rootTs;
         rootTs.allowNear(false);
         int roots = rootTs.intersect(q2, *testLines[index]);
         for (int idx2 = 0; idx2 < roots; ++idx2) {
             double t = rootTs[0][idx2];
-#ifdef SK_DEBUG
+#if 0 // def SK_DEBUG   // FIXME : accurate for error = 16, error of 17.5 seen
+// {{{136.08723965397621, 1648.2814535211637}, {593.49031197259478, 1190.8784277439891}, {593.49031197259478, 544.0128173828125}}}
+// {{{-968.181396484375, 544.0128173828125}, {592.2825927734375, 870.552490234375}, {593.435302734375, 557.8828125}}}
+
             SkDPoint qPt = q2.ptAtT(t);
             SkDPoint lPt = testLines[index]->ptAtT(rootTs[1][idx2]);
-            SkASSERT(qPt.approximatelyPEqual(lPt));
+            SkASSERT(qPt.approximatelyDEqual(lPt));
 #endif
             if (approximately_negative(t - t2s) || approximately_positive(t - t2e)) {
                 continue;
             }
             tsFound.push_back(rootTs[0][idx2]);
         }
     }
     int tCount = tsFound.count();
     if (tCount <= 0) {
         return true;
@@ skipping 122 matching lines @@
         if (calcMask & (1 << 1)) t1[1] = quad1.ptAtT(*t1Seed);
         if (calcMask & (1 << 4)) t2[1] = quad2.ptAtT(*t2Seed);
         if (t1[1].approximatelyEqual(t2[1])) {
             *pt = t1[1];
     #if ONE_OFF_DEBUG
             SkDebugf("%s t1=%1.9g t2=%1.9g (%1.9g,%1.9g) == (%1.9g,%1.9g)\n", __FUNCTION__,
                     t1Seed, t2Seed, t1[1].fX, t1[1].fY, t2[1].fX, t2[1].fY);
     #endif
             return true;
         }
-        if (calcMask & (1 << 0)) t1[0] = quad1.ptAtT(*t1Seed - tStep);
-        if (calcMask & (1 << 2)) t1[2] = quad1.ptAtT(*t1Seed + tStep);
-        if (calcMask & (1 << 3)) t2[0] = quad2.ptAtT(*t2Seed - tStep);
-        if (calcMask & (1 << 5)) t2[2] = quad2.ptAtT(*t2Seed + tStep);
+        if (calcMask & (1 << 0)) t1[0] = quad1.ptAtT(SkTMax(0., *t1Seed - tStep));
+        if (calcMask & (1 << 2)) t1[2] = quad1.ptAtT(SkTMin(1., *t1Seed + tStep));
+        if (calcMask & (1 << 3)) t2[0] = quad2.ptAtT(SkTMax(0., *t2Seed - tStep));
+        if (calcMask & (1 << 5)) t2[2] = quad2.ptAtT(SkTMin(1., *t2Seed + tStep));
         double dist[3][3];
         // OPTIMIZE: using calcMask value permits skipping some distance calcuations
         //   if prior loop's results are moved to correct slot for reuse
         dist[1][1] = t1[1].distanceSquared(t2[1]);
         int best_i = 1, best_j = 1;
         for (int i = 0; i < 3; ++i) {
             for (int j = 0; j < 3; ++j) {
                 if (i == 1 && j == 1) {
                     continue;
                 }
@@ skipping 54 matching lines @@
     }
     SkDLine tmpLine;
     int testTIndex = testT << 1;
     tmpLine[0] = tmpLine[1] = q2[testTIndex];
     tmpLine[1].fX += q2[1].fY - q2[testTIndex].fY;
     tmpLine[1].fY -= q2[1].fX - q2[testTIndex].fX;
     SkIntersections impTs;
     impTs.intersectRay(q1, tmpLine);
     for (int index = 0; index < impTs.used(); ++index) {
         SkDPoint realPt = impTs.pt(index);
-        if (!tmpLine[0].approximatelyEqual(realPt)) {
+        if (!tmpLine[0].approximatelyPEqual(realPt)) {
             continue;
         }
         if (swap) {
             i->insert(testT, impTs[0][index], tmpLine[0]);
         } else {
             i->insert(impTs[0][index], testT, tmpLine[0]);
         }
     }
 }
 
@@ skipping 147 matching lines @@
         }
         if (lowestIndex < 0) {
             break;
         }
         insert(roots1Copy[lowestIndex], roots2Copy[closest[lowestIndex]],
                 pts1[lowestIndex]);
         closest[lowestIndex] = -1;
     } while (++used < r1Count);
     return fUsed;
 }