fix battlefield website by disallowing very small coordinates

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 "SkIntersections.h"
 #include "SkOpAngle.h"
 #include "SkOpSegment.h"
 #include "SkPathOpsCurve.h"
@@ skipping 268 matching lines @@
         return true;
     }
     return m0xm1 < 0;
 }
 
 // the original angle is too short to get meaningful sector information
 // lengthen it until it is long enough to be meaningful or leave it unset if lengthening it
 // would cause it to intersect one of the adjacent angles
 bool SkOpAngle::computeSector() {
     if (fComputedSector) {
-        // FIXME: logically, this should return !fUnorderable, but doing so breaks testQuadratic51
-        // -- but in general, this code may not work so this may be the least of problems
-        // adding the bang fixes testQuads46x in release, however
         return !fUnorderable;
     }
-    SkASSERT(fSegment->verb() != SkPath::kLine_Verb && small());
+//    SkASSERT(fSegment->verb() != SkPath::kLine_Verb && small());
     fComputedSector = true;
     int step = fStart < fEnd ? 1 : -1;
     int limit = step > 0 ? fSegment->count() : -1;
     int checkEnd = fEnd;
     do {
 // advance end
         const SkOpSpan& span = fSegment->span(checkEnd);
         const SkOpSegment* other = span.fOther;
         int oCount = other->count();
         for (int oIndex = 0; oIndex < oCount; ++oIndex) {
@@ skipping 321 matching lines @@
     // one could coin the term sedecimant for a space divided into 16 sections.
    // http://english.stackexchange.com/questions/133688/word-for-something-partitioned-into-16-parts
     static const int sedecimant[3][3][3] = {
     //       y<0           y==0           y>0
     //   x<0 x==0 x>0  x<0 x==0 x>0  x<0 x==0 x>0
         {{ 4,  3,  2}, { 7, -1, 15}, {10, 11, 12}},  // abs(x) <  abs(y)
         {{ 5, -1,  1}, {-1, -1, -1}, { 9, -1, 13}},  // abs(x) == abs(y)
         {{ 6,  3,  0}, { 7, -1, 15}, { 8, 11, 14}},  // abs(x) >  abs(y)
     };
     int sector = sedecimant[(xy >= 0) + (xy > 0)][(y >= 0) + (y > 0)][(x >= 0) + (x > 0)] * 2 + 1;
-    SkASSERT(SkPath::kLine_Verb == verb || sector >= 0);
+//    SkASSERT(SkPath::kLine_Verb == verb || sector >= 0);
     return sector;
 }
 
 // OPTIMIZE: if this loops to only one other angle, after first compare fails, insert on other side
 // OPTIMIZE: return where insertion succeeded. Then, start next insertion on opposite side
 void SkOpAngle::insert(SkOpAngle* angle) {
     if (angle->fNext) {
         if (loopCount() >= angle->loopCount()) {
             if (!merge(angle)) {
                 return;
@@ skipping 280 matching lines @@
         SkASSERT(s2x1 * s1x3 > 0);
         fSweep[0] = fSweep[1];
         fUnorderedSweep = true;
     }
     fSweep[1] = thirdSweep;
 }
 
 void SkOpAngle::setSector() {
     SkPath::Verb verb = fSegment->verb();
     if (SkPath::kLine_Verb != verb && small()) {
-        fSectorStart = fSectorEnd = -1;
-        fSectorMask = 0;
-        fComputeSector = true;  // can't determine sector until segment length can be found
-        return;
+        goto deferTilLater;
     }
     fSectorStart = findSector(verb, fSweep[0].fX, fSweep[0].fY);
+    if (fSectorStart < 0) {
+        goto deferTilLater;
+    }
     if (!fIsCurve) {  // if it's a line or line-like, note that both sectors are the same
         SkASSERT(fSectorStart >= 0);
         fSectorEnd = fSectorStart;
         fSectorMask = 1 << fSectorStart;
         return;
     }
     SkASSERT(SkPath::kLine_Verb != verb);
     fSectorEnd = findSector(verb, fSweep[1].fX, fSweep[1].fY);
+    if (fSectorEnd < 0) {
+deferTilLater:
+        fSectorStart = fSectorEnd = -1;
+        fSectorMask = 0;
+        fComputeSector = true;  // can't determine sector until segment length can be found
+        return;
+    }
     if (fSectorEnd == fSectorStart) {
         SkASSERT((fSectorStart & 3) != 3);  // if the sector has no span, it can't be an exact angle
         fSectorMask = 1 << fSectorStart;
         return;
     }
     bool crossesZero = checkCrossesZero();
     int start = SkTMin(fSectorStart, fSectorEnd);
     bool curveBendsCCW = (fSectorStart == start) ^ crossesZero;
     // bump the start and end of the sector span if they are on exact compass points
     if ((fSectorStart & 3) == 3) {
@@ skipping 156 matching lines @@
     angle->setID(++fCount);
 #endif
     return *angle;
 }
 
 void SkOpAngleSet::reset() {
     if (fAngles) {
         fAngles->reset();
     }
 }