michael@0: /*
michael@0:  * Copyright 2012 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: #include "SkAddIntersections.h"
michael@0: #include "SkPathOpsBounds.h"
michael@0: 
michael@0: #if DEBUG_ADD_INTERSECTING_TS
michael@0: 
michael@0: static void debugShowLineIntersection(int pts, const SkIntersectionHelper& wt,
michael@0:                                       const SkIntersectionHelper& wn, const SkIntersections& i) {
michael@0:     SkASSERT(i.used() == pts);
michael@0:     if (!pts) {
michael@0:         SkDebugf("%s no intersect " LINE_DEBUG_STR " " LINE_DEBUG_STR "\n",
michael@0:                 __FUNCTION__, LINE_DEBUG_DATA(wt.pts()), LINE_DEBUG_DATA(wn.pts()));
michael@0:         return;
michael@0:     }
michael@0:     SkDebugf("%s " T_DEBUG_STR(wtTs, 0) " " LINE_DEBUG_STR " " PT_DEBUG_STR, __FUNCTION__,
michael@0:             i[0][0], LINE_DEBUG_DATA(wt.pts()), PT_DEBUG_DATA(i, 0));
michael@0:     if (pts == 2) {
michael@0:         SkDebugf(" " T_DEBUG_STR(wtTs, 1) " " PT_DEBUG_STR, i[0][1], PT_DEBUG_DATA(i, 1));
michael@0:     }
michael@0:     SkDebugf(" wnTs[0]=%g " LINE_DEBUG_STR, i[1][0], LINE_DEBUG_DATA(wn.pts()));
michael@0:     if (pts == 2) {
michael@0:         SkDebugf(" " T_DEBUG_STR(wnTs, 1), i[1][1]);
michael@0:     }
michael@0:     SkDebugf("\n");
michael@0: }
michael@0: 
michael@0: static void debugShowQuadLineIntersection(int pts, const SkIntersectionHelper& wt,
michael@0:                                           const SkIntersectionHelper& wn,
michael@0:                                           const SkIntersections& i) {
michael@0:     SkASSERT(i.used() == pts);
michael@0:     if (!pts) {
michael@0:         SkDebugf("%s no intersect " QUAD_DEBUG_STR " " LINE_DEBUG_STR "\n",
michael@0:                 __FUNCTION__, QUAD_DEBUG_DATA(wt.pts()), LINE_DEBUG_DATA(wn.pts()));
michael@0:         return;
michael@0:     }
michael@0:     SkDebugf("%s " T_DEBUG_STR(wtTs, 0) " " QUAD_DEBUG_STR " " PT_DEBUG_STR, __FUNCTION__,
michael@0:             i[0][0], QUAD_DEBUG_DATA(wt.pts()), PT_DEBUG_DATA(i, 0));
michael@0:     for (int n = 1; n < pts; ++n) {
michael@0:         SkDebugf(" " TX_DEBUG_STR(wtTs) " " PT_DEBUG_STR, n, i[0][n], PT_DEBUG_DATA(i, n));
michael@0:     }
michael@0:     SkDebugf(" wnTs[0]=%g " LINE_DEBUG_STR, i[1][0], LINE_DEBUG_DATA(wn.pts()));
michael@0:     for (int n = 1; n < pts; ++n) {
michael@0:         SkDebugf(" " TX_DEBUG_STR(wnTs), n, i[1][n]);
michael@0:     }
michael@0:     SkDebugf("\n");
michael@0: }
michael@0: 
michael@0: static void debugShowQuadIntersection(int pts, const SkIntersectionHelper& wt,
michael@0:         const SkIntersectionHelper& wn, const SkIntersections& i) {
michael@0:     SkASSERT(i.used() == pts);
michael@0:     if (!pts) {
michael@0:         SkDebugf("%s no intersect " QUAD_DEBUG_STR " " QUAD_DEBUG_STR "\n",
michael@0:                 __FUNCTION__, QUAD_DEBUG_DATA(wt.pts()), QUAD_DEBUG_DATA(wn.pts()));
michael@0:         return;
michael@0:     }
michael@0:     SkDebugf("%s " T_DEBUG_STR(wtTs, 0) " " QUAD_DEBUG_STR " " PT_DEBUG_STR, __FUNCTION__,
michael@0:             i[0][0], QUAD_DEBUG_DATA(wt.pts()), PT_DEBUG_DATA(i, 0));
michael@0:     for (int n = 1; n < pts; ++n) {
michael@0:         SkDebugf(" " TX_DEBUG_STR(wtTs) " " PT_DEBUG_STR, n, i[0][n], PT_DEBUG_DATA(i, n));
michael@0:     }
michael@0:     SkDebugf(" wnTs[0]=%g " QUAD_DEBUG_STR, i[1][0], QUAD_DEBUG_DATA(wn.pts()));
michael@0:     for (int n = 1; n < pts; ++n) {
michael@0:         SkDebugf(" " TX_DEBUG_STR(wnTs), n, i[1][n]);
michael@0:     }
michael@0:     SkDebugf("\n");
michael@0: }
michael@0: 
michael@0: static void debugShowCubicLineIntersection(int pts, const SkIntersectionHelper& wt,
michael@0:         const SkIntersectionHelper& wn, const SkIntersections& i) {
michael@0:     SkASSERT(i.used() == pts);
michael@0:     if (!pts) {
michael@0:         SkDebugf("%s no intersect " CUBIC_DEBUG_STR " " LINE_DEBUG_STR "\n",
michael@0:                 __FUNCTION__, CUBIC_DEBUG_DATA(wt.pts()), LINE_DEBUG_DATA(wn.pts()));
michael@0:         return;
michael@0:     }
michael@0:     SkDebugf("%s " T_DEBUG_STR(wtTs, 0) " " CUBIC_DEBUG_STR " " PT_DEBUG_STR, __FUNCTION__,
michael@0:             i[0][0], CUBIC_DEBUG_DATA(wt.pts()), PT_DEBUG_DATA(i, 0));
michael@0:     for (int n = 1; n < pts; ++n) {
michael@0:         SkDebugf(" " TX_DEBUG_STR(wtTs) " " PT_DEBUG_STR, n, i[0][n], PT_DEBUG_DATA(i, n));
michael@0:     }
michael@0:     SkDebugf(" wnTs[0]=%g " LINE_DEBUG_STR, i[1][0], LINE_DEBUG_DATA(wn.pts()));
michael@0:     for (int n = 1; n < pts; ++n) {
michael@0:         SkDebugf(" " TX_DEBUG_STR(wnTs), n, i[1][n]);
michael@0:     }
michael@0:     SkDebugf("\n");
michael@0: }
michael@0: 
michael@0: static void debugShowCubicQuadIntersection(int pts, const SkIntersectionHelper& wt,
michael@0:         const SkIntersectionHelper& wn, const SkIntersections& i) {
michael@0:     SkASSERT(i.used() == pts);
michael@0:     if (!pts) {
michael@0:         SkDebugf("%s no intersect " CUBIC_DEBUG_STR " " QUAD_DEBUG_STR "\n",
michael@0:                 __FUNCTION__, CUBIC_DEBUG_DATA(wt.pts()), QUAD_DEBUG_DATA(wn.pts()));
michael@0:         return;
michael@0:     }
michael@0:     SkDebugf("%s " T_DEBUG_STR(wtTs, 0) " " CUBIC_DEBUG_STR " " PT_DEBUG_STR, __FUNCTION__,
michael@0:             i[0][0], CUBIC_DEBUG_DATA(wt.pts()), PT_DEBUG_DATA(i, 0));
michael@0:     for (int n = 1; n < pts; ++n) {
michael@0:         SkDebugf(" " TX_DEBUG_STR(wtTs) " " PT_DEBUG_STR, n, i[0][n], PT_DEBUG_DATA(i, n));
michael@0:     }
michael@0:     SkDebugf(" wnTs[0]=%g " QUAD_DEBUG_STR, i[1][0], QUAD_DEBUG_DATA(wn.pts()));
michael@0:     for (int n = 1; n < pts; ++n) {
michael@0:         SkDebugf(" " TX_DEBUG_STR(wnTs), n, i[1][n]);
michael@0:     }
michael@0:     SkDebugf("\n");
michael@0: }
michael@0: 
michael@0: static void debugShowCubicIntersection(int pts, const SkIntersectionHelper& wt,
michael@0:         const SkIntersectionHelper& wn, const SkIntersections& i) {
michael@0:     SkASSERT(i.used() == pts);
michael@0:     if (!pts) {
michael@0:         SkDebugf("%s no intersect " CUBIC_DEBUG_STR " " CUBIC_DEBUG_STR "\n",
michael@0:                 __FUNCTION__, CUBIC_DEBUG_DATA(wt.pts()), CUBIC_DEBUG_DATA(wn.pts()));
michael@0:         return;
michael@0:     }
michael@0:     SkDebugf("%s " T_DEBUG_STR(wtTs, 0) " " CUBIC_DEBUG_STR " " PT_DEBUG_STR, __FUNCTION__,
michael@0:             i[0][0], CUBIC_DEBUG_DATA(wt.pts()), PT_DEBUG_DATA(i, 0));
michael@0:     for (int n = 1; n < pts; ++n) {
michael@0:         SkDebugf(" " TX_DEBUG_STR(wtTs) " " PT_DEBUG_STR, n, i[0][n], PT_DEBUG_DATA(i, n));
michael@0:     }
michael@0:     SkDebugf(" wnTs[0]=%g " CUBIC_DEBUG_STR, i[1][0], CUBIC_DEBUG_DATA(wn.pts()));
michael@0:     for (int n = 1; n < pts; ++n) {
michael@0:         SkDebugf(" " TX_DEBUG_STR(wnTs), n, i[1][n]);
michael@0:     }
michael@0:     SkDebugf("\n");
michael@0: }
michael@0: 
michael@0: static void debugShowCubicIntersection(int pts, const SkIntersectionHelper& wt,
michael@0:         const SkIntersections& i) {
michael@0:     SkASSERT(i.used() == pts);
michael@0:     if (!pts) {
michael@0:         SkDebugf("%s no self intersect " CUBIC_DEBUG_STR "\n", __FUNCTION__,
michael@0:                 CUBIC_DEBUG_DATA(wt.pts()));
michael@0:         return;
michael@0:     }
michael@0:     SkDebugf("%s " T_DEBUG_STR(wtTs, 0) " " CUBIC_DEBUG_STR " " PT_DEBUG_STR, __FUNCTION__,
michael@0:             i[0][0], CUBIC_DEBUG_DATA(wt.pts()), PT_DEBUG_DATA(i, 0));
michael@0:     SkDebugf(" " T_DEBUG_STR(wtTs, 1), i[1][0]);
michael@0:     SkDebugf("\n");
michael@0: }
michael@0: 
michael@0: #else
michael@0: static void debugShowLineIntersection(int , const SkIntersectionHelper& ,
michael@0:         const SkIntersectionHelper& , const SkIntersections& ) {
michael@0: }
michael@0: 
michael@0: static void debugShowQuadLineIntersection(int , const SkIntersectionHelper& ,
michael@0:         const SkIntersectionHelper& , const SkIntersections& ) {
michael@0: }
michael@0: 
michael@0: static void debugShowQuadIntersection(int , const SkIntersectionHelper& ,
michael@0:         const SkIntersectionHelper& , const SkIntersections& ) {
michael@0: }
michael@0: 
michael@0: static void debugShowCubicLineIntersection(int , const SkIntersectionHelper& ,
michael@0:         const SkIntersectionHelper& , const SkIntersections& ) {
michael@0: }
michael@0: 
michael@0: static void debugShowCubicQuadIntersection(int , const SkIntersectionHelper& ,
michael@0:         const SkIntersectionHelper& , const SkIntersections& ) {
michael@0: }
michael@0: 
michael@0: static void debugShowCubicIntersection(int , const SkIntersectionHelper& ,
michael@0:         const SkIntersectionHelper& , const SkIntersections& ) {
michael@0: }
michael@0: 
michael@0: static void debugShowCubicIntersection(int , const SkIntersectionHelper& ,
michael@0:         const SkIntersections& ) {
michael@0: }
michael@0: #endif
michael@0: 
michael@0: bool AddIntersectTs(SkOpContour* test, SkOpContour* next) {
michael@0:     if (test != next) {
michael@0:         if (AlmostLessUlps(test->bounds().fBottom, next->bounds().fTop)) {
michael@0:             return false;
michael@0:         }
michael@0:         // OPTIMIZATION: outset contour bounds a smidgen instead?
michael@0:         if (!SkPathOpsBounds::Intersects(test->bounds(), next->bounds())) {
michael@0:             return true;
michael@0:         }
michael@0:     }
michael@0:     SkIntersectionHelper wt;
michael@0:     wt.init(test);
michael@0:     bool foundCommonContour = test == next;
michael@0:     do {
michael@0:         SkIntersectionHelper wn;
michael@0:         wn.init(next);
michael@0:         if (test == next && !wn.startAfter(wt)) {
michael@0:             continue;
michael@0:         }
michael@0:         do {
michael@0:             if (!SkPathOpsBounds::Intersects(wt.bounds(), wn.bounds())) {
michael@0:                 continue;
michael@0:             }
michael@0:             int pts = 0;
michael@0:             SkIntersections ts;
michael@0:             bool swap = false;
michael@0:             switch (wt.segmentType()) {
michael@0:                 case SkIntersectionHelper::kHorizontalLine_Segment:
michael@0:                     swap = true;
michael@0:                     switch (wn.segmentType()) {
michael@0:                         case SkIntersectionHelper::kHorizontalLine_Segment:
michael@0:                         case SkIntersectionHelper::kVerticalLine_Segment:
michael@0:                         case SkIntersectionHelper::kLine_Segment: {
michael@0:                             pts = ts.lineHorizontal(wn.pts(), wt.left(),
michael@0:                                     wt.right(), wt.y(), wt.xFlipped());
michael@0:                             debugShowLineIntersection(pts, wn, wt, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         case SkIntersectionHelper::kQuad_Segment: {
michael@0:                             pts = ts.quadHorizontal(wn.pts(), wt.left(),
michael@0:                                     wt.right(), wt.y(), wt.xFlipped());
michael@0:                             debugShowQuadLineIntersection(pts, wn, wt, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         case SkIntersectionHelper::kCubic_Segment: {
michael@0:                             pts = ts.cubicHorizontal(wn.pts(), wt.left(),
michael@0:                                     wt.right(), wt.y(), wt.xFlipped());
michael@0:                             debugShowCubicLineIntersection(pts, wn, wt, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         default:
michael@0:                             SkASSERT(0);
michael@0:                     }
michael@0:                     break;
michael@0:                 case SkIntersectionHelper::kVerticalLine_Segment:
michael@0:                     swap = true;
michael@0:                     switch (wn.segmentType()) {
michael@0:                         case SkIntersectionHelper::kHorizontalLine_Segment:
michael@0:                         case SkIntersectionHelper::kVerticalLine_Segment:
michael@0:                         case SkIntersectionHelper::kLine_Segment: {
michael@0:                             pts = ts.lineVertical(wn.pts(), wt.top(),
michael@0:                                     wt.bottom(), wt.x(), wt.yFlipped());
michael@0:                             debugShowLineIntersection(pts, wn, wt, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         case SkIntersectionHelper::kQuad_Segment: {
michael@0:                             pts = ts.quadVertical(wn.pts(), wt.top(),
michael@0:                                     wt.bottom(), wt.x(), wt.yFlipped());
michael@0:                             debugShowQuadLineIntersection(pts, wn, wt, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         case SkIntersectionHelper::kCubic_Segment: {
michael@0:                             pts = ts.cubicVertical(wn.pts(), wt.top(),
michael@0:                                     wt.bottom(), wt.x(), wt.yFlipped());
michael@0:                             debugShowCubicLineIntersection(pts, wn, wt, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         default:
michael@0:                             SkASSERT(0);
michael@0:                     }
michael@0:                     break;
michael@0:                 case SkIntersectionHelper::kLine_Segment:
michael@0:                     switch (wn.segmentType()) {
michael@0:                         case SkIntersectionHelper::kHorizontalLine_Segment:
michael@0:                             pts = ts.lineHorizontal(wt.pts(), wn.left(),
michael@0:                                     wn.right(), wn.y(), wn.xFlipped());
michael@0:                             debugShowLineIntersection(pts, wt, wn, ts);
michael@0:                             break;
michael@0:                         case SkIntersectionHelper::kVerticalLine_Segment:
michael@0:                             pts = ts.lineVertical(wt.pts(), wn.top(),
michael@0:                                     wn.bottom(), wn.x(), wn.yFlipped());
michael@0:                             debugShowLineIntersection(pts, wt, wn, ts);
michael@0:                             break;
michael@0:                         case SkIntersectionHelper::kLine_Segment: {
michael@0:                             pts = ts.lineLine(wt.pts(), wn.pts());
michael@0:                             debugShowLineIntersection(pts, wt, wn, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         case SkIntersectionHelper::kQuad_Segment: {
michael@0:                             swap = true;
michael@0:                             pts = ts.quadLine(wn.pts(), wt.pts());
michael@0:                             debugShowQuadLineIntersection(pts, wn, wt, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         case SkIntersectionHelper::kCubic_Segment: {
michael@0:                             swap = true;
michael@0:                             pts = ts.cubicLine(wn.pts(), wt.pts());
michael@0:                             debugShowCubicLineIntersection(pts, wn, wt,  ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         default:
michael@0:                             SkASSERT(0);
michael@0:                     }
michael@0:                     break;
michael@0:                 case SkIntersectionHelper::kQuad_Segment:
michael@0:                     switch (wn.segmentType()) {
michael@0:                         case SkIntersectionHelper::kHorizontalLine_Segment:
michael@0:                             pts = ts.quadHorizontal(wt.pts(), wn.left(),
michael@0:                                     wn.right(), wn.y(), wn.xFlipped());
michael@0:                             debugShowQuadLineIntersection(pts, wt, wn, ts);
michael@0:                             break;
michael@0:                         case SkIntersectionHelper::kVerticalLine_Segment:
michael@0:                             pts = ts.quadVertical(wt.pts(), wn.top(),
michael@0:                                     wn.bottom(), wn.x(), wn.yFlipped());
michael@0:                             debugShowQuadLineIntersection(pts, wt, wn, ts);
michael@0:                             break;
michael@0:                         case SkIntersectionHelper::kLine_Segment: {
michael@0:                             pts = ts.quadLine(wt.pts(), wn.pts());
michael@0:                             debugShowQuadLineIntersection(pts, wt, wn, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         case SkIntersectionHelper::kQuad_Segment: {
michael@0:                             pts = ts.quadQuad(wt.pts(), wn.pts());
michael@0:                             debugShowQuadIntersection(pts, wt, wn, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         case SkIntersectionHelper::kCubic_Segment: {
michael@0:                             swap = true;
michael@0:                             pts = ts.cubicQuad(wn.pts(), wt.pts());
michael@0:                             debugShowCubicQuadIntersection(pts, wn, wt, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         default:
michael@0:                             SkASSERT(0);
michael@0:                     }
michael@0:                     break;
michael@0:                 case SkIntersectionHelper::kCubic_Segment:
michael@0:                     switch (wn.segmentType()) {
michael@0:                         case SkIntersectionHelper::kHorizontalLine_Segment:
michael@0:                             pts = ts.cubicHorizontal(wt.pts(), wn.left(),
michael@0:                                     wn.right(), wn.y(), wn.xFlipped());
michael@0:                             debugShowCubicLineIntersection(pts, wt, wn, ts);
michael@0:                             break;
michael@0:                         case SkIntersectionHelper::kVerticalLine_Segment:
michael@0:                             pts = ts.cubicVertical(wt.pts(), wn.top(),
michael@0:                                     wn.bottom(), wn.x(), wn.yFlipped());
michael@0:                             debugShowCubicLineIntersection(pts, wt, wn, ts);
michael@0:                             break;
michael@0:                         case SkIntersectionHelper::kLine_Segment: {
michael@0:                             pts = ts.cubicLine(wt.pts(), wn.pts());
michael@0:                             debugShowCubicLineIntersection(pts, wt, wn, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         case SkIntersectionHelper::kQuad_Segment: {
michael@0:                             pts = ts.cubicQuad(wt.pts(), wn.pts());
michael@0:                             debugShowCubicQuadIntersection(pts, wt, wn, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         case SkIntersectionHelper::kCubic_Segment: {
michael@0:                             pts = ts.cubicCubic(wt.pts(), wn.pts());
michael@0:                             debugShowCubicIntersection(pts, wt, wn, ts);
michael@0:                             break;
michael@0:                         }
michael@0:                         default:
michael@0:                             SkASSERT(0);
michael@0:                     }
michael@0:                     break;
michael@0:                 default:
michael@0:                     SkASSERT(0);
michael@0:             }
michael@0:             if (!foundCommonContour && pts > 0) {
michael@0:                 test->addCross(next);
michael@0:                 next->addCross(test);
michael@0:                 foundCommonContour = true;
michael@0:             }
michael@0:             // in addition to recording T values, record matching segment
michael@0:             if (pts == 2) {
michael@0:                 if (wn.segmentType() <= SkIntersectionHelper::kLine_Segment
michael@0:                         && wt.segmentType() <= SkIntersectionHelper::kLine_Segment) {
michael@0:                     if (wt.addCoincident(wn, ts, swap)) {
michael@0:                         continue;
michael@0:                     }
michael@0:                     ts.cleanUpCoincidence();  // prefer (t == 0 or t == 1)
michael@0:                     pts = 1;
michael@0:                 } else if (wn.segmentType() >= SkIntersectionHelper::kQuad_Segment
michael@0:                         && wt.segmentType() >= SkIntersectionHelper::kQuad_Segment
michael@0:                         && ts.isCoincident(0)) {
michael@0:                     SkASSERT(ts.coincidentUsed() == 2);
michael@0:                     if (wt.addCoincident(wn, ts, swap)) {
michael@0:                         continue;
michael@0:                     }
michael@0:                     ts.cleanUpCoincidence();  // prefer (t == 0 or t == 1)
michael@0:                     pts = 1;
michael@0:                 }
michael@0:             }
michael@0:             if (pts >= 2) {
michael@0:                 for (int pt = 0; pt < pts - 1; ++pt) {
michael@0:                     const SkDPoint& point = ts.pt(pt);
michael@0:                     const SkDPoint& next = ts.pt(pt + 1);
michael@0:                     if (wt.isPartial(ts[swap][pt], ts[swap][pt + 1], point, next)
michael@0:                             && wn.isPartial(ts[!swap][pt], ts[!swap][pt + 1], point, next)) {
michael@0:                         if (!wt.addPartialCoincident(wn, ts, pt, swap)) {
michael@0:                             // remove extra point if two map to same float values
michael@0:                             ts.cleanUpCoincidence();  // prefer (t == 0 or t == 1)
michael@0:                             pts = 1;
michael@0:                         }
michael@0:                     }
michael@0:                 }
michael@0:             }
michael@0:             for (int pt = 0; pt < pts; ++pt) {
michael@0:                 SkASSERT(ts[0][pt] >= 0 && ts[0][pt] <= 1);
michael@0:                 SkASSERT(ts[1][pt] >= 0 && ts[1][pt] <= 1);
michael@0:                 SkPoint point = ts.pt(pt).asSkPoint();
michael@0:                 int testTAt = wt.addT(wn, point, ts[swap][pt]);
michael@0:                 int nextTAt = wn.addT(wt, point, ts[!swap][pt]);
michael@0:                 wt.addOtherT(testTAt, ts[!swap][pt], nextTAt);
michael@0:                 wn.addOtherT(nextTAt, ts[swap][pt], testTAt);
michael@0:             }
michael@0:         } while (wn.advance());
michael@0:     } while (wt.advance());
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: void AddSelfIntersectTs(SkOpContour* test) {
michael@0:     SkIntersectionHelper wt;
michael@0:     wt.init(test);
michael@0:     do {
michael@0:         if (wt.segmentType() != SkIntersectionHelper::kCubic_Segment) {
michael@0:             continue;
michael@0:         }
michael@0:         SkIntersections ts;
michael@0:         int pts = ts.cubic(wt.pts());
michael@0:         debugShowCubicIntersection(pts, wt, ts);
michael@0:         if (!pts) {
michael@0:             continue;
michael@0:         }
michael@0:         SkASSERT(pts == 1);
michael@0:         SkASSERT(ts[0][0] >= 0 && ts[0][0] <= 1);
michael@0:         SkASSERT(ts[1][0] >= 0 && ts[1][0] <= 1);
michael@0:         SkPoint point = ts.pt(0).asSkPoint();
michael@0:         int testTAt = wt.addSelfT(wt, point, ts[0][0]);
michael@0:         int nextTAt = wt.addT(wt, point, ts[1][0]);
michael@0:         wt.addOtherT(testTAt, ts[1][0], nextTAt);
michael@0:         wt.addOtherT(nextTAt, ts[0][0], testTAt);
michael@0:     } while (wt.advance());
michael@0: }
michael@0: 
michael@0: // resolve any coincident pairs found while intersecting, and
michael@0: // see if coincidence is formed by clipping non-concident segments
michael@0: void CoincidenceCheck(SkTArray<SkOpContour*, true>* contourList, int total) {
michael@0:     int contourCount = (*contourList).count();
michael@0:     for (int cIndex = 0; cIndex < contourCount; ++cIndex) {
michael@0:         SkOpContour* contour = (*contourList)[cIndex];
michael@0:         contour->addCoincidentPoints();
michael@0:     }
michael@0:     for (int cIndex = 0; cIndex < contourCount; ++cIndex) {
michael@0:         SkOpContour* contour = (*contourList)[cIndex];
michael@0:         contour->calcCoincidentWinding();
michael@0:     }
michael@0:     for (int cIndex = 0; cIndex < contourCount; ++cIndex) {
michael@0:         SkOpContour* contour = (*contourList)[cIndex];
michael@0:         contour->calcPartialCoincidentWinding();
michael@0:     }
michael@0: }