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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 11:50:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 11:50:49 +0000
commitc853ffb5b2f75f5a889ed2e3ef89b818a736e87a (patch)
tree7d13a0883bb7936b84d6ecdd7bc332b41ed04bee /src/livarot/ShapeSweep.cpp
parentInitial commit. (diff)
downloadinkscape-c853ffb5b2f75f5a889ed2e3ef89b818a736e87a.tar.xz
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Adding upstream version 1.3+ds.upstream/1.3+dsupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/livarot/ShapeSweep.cpp')
-rw-r--r--src/livarot/ShapeSweep.cpp3637
1 files changed, 3637 insertions, 0 deletions
diff --git a/src/livarot/ShapeSweep.cpp b/src/livarot/ShapeSweep.cpp
new file mode 100644
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--- /dev/null
+++ b/src/livarot/ShapeSweep.cpp
@@ -0,0 +1,3637 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/** @file
+ * TODO: insert short description here
+ *//*
+ * Authors:
+ * see git history
+ * Fred
+ *
+ * Copyright (C) 2018 Authors
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+#include <glib.h>
+#include <2geom/affine.h>
+#include "Shape.h"
+#include "livarot/sweep-event-queue.h"
+#include "livarot/sweep-tree-list.h"
+#include "livarot/sweep-tree.h"
+
+//int doDebug=0;
+
+/*
+ * El Intersector.
+ * algorithm: 1) benley ottman to get intersections of all the polygon's edges
+ * 2) rounding of the points of the polygon, Hooby's algorithm
+ * 3) DFS with clockwise choice of the edge to compute the windings
+ * 4) choose edges according to winding numbers and fill rule
+ * some additional nastyness: step 2 needs a seed winding number for the upper-left point of each
+ * connex subgraph of the graph. computing these brutally is O(n^3): baaaad. so during the sweeping in 1)
+ * we keep for each point the edge of the resulting graph (not the original) that lies just on its left;
+ * when the time comes for the point to get its winding number computed, that edge must have been treated,
+ * because its upper end lies above the aforementioned point, meaning we know the winding number of the point.
+ * only, there is a catch: since we're sweeping the polygon, the edge we want to link the point to has not yet been
+ * added (that would be too easy...). so the points are put on a linked list on the original shape's edge, and the list
+ * is flushed when the edge is added.
+ * rounding: to do the rounding, we need to find which edges cross the surrounding of the rounded points (at
+ * each sweepline position). grunt method tries all combination of "rounded points in the sweepline"x"edges crossing
+ * the sweepline". That's bad (and that's what polyboolean does, if i am not mistaken). so for each point
+ * rounded in a given sweepline, keep immediate left and right edges at the time the point is treated.
+ * when edges/points crossing are searched, walk the edge list (in the sweepline at the end of the batch) starting
+ * from the rounded points' left and right from that time. may sound strange, but it works because edges that
+ * end or start in the batch have at least one end in the batch.
+ * all these are the cause of the numerous linked lists of points and edges maintained in the sweeping
+ */
+
+void
+Shape::ResetSweep ()
+{
+ MakePointData (true);
+ MakeEdgeData (true);
+ MakeSweepSrcData (true);
+}
+
+void
+Shape::CleanupSweep ()
+{
+ MakePointData (false);
+ MakeEdgeData (false);
+ MakeSweepSrcData (false);
+}
+
+void
+Shape::ForceToPolygon ()
+{
+ type = shape_polygon;
+}
+
+int
+Shape::Reoriente (Shape * a)
+{
+ Reset (0, 0);
+ if (a->numberOfPoints() <= 1 || a->numberOfEdges() <= 1)
+ return 0;
+ if (directedEulerian(a) == false)
+ return shape_input_err;
+
+ _pts = a->_pts;
+ if (numberOfPoints() > maxPt)
+ {
+ maxPt = numberOfPoints();
+ if (_has_points_data) {
+ pData.resize(maxPt);
+ _point_data_initialised = false;
+ _bbox_up_to_date = false;
+ }
+ }
+
+ _aretes = a->_aretes;
+ if (numberOfEdges() > maxAr)
+ {
+ maxAr = numberOfEdges();
+ if (_has_edges_data)
+ eData.resize(maxAr);
+ if (_has_sweep_src_data)
+ swsData.resize(maxAr);
+ if (_has_sweep_dest_data)
+ swdData.resize(maxAr);
+ if (_has_raster_data)
+ swrData.resize(maxAr);
+ }
+
+ MakePointData (true);
+ MakeEdgeData (true);
+ MakeSweepDestData (true);
+
+ initialisePointData();
+
+ for (int i = 0; i < numberOfPoints(); i++) {
+ _pts[i].x = pData[i].rx;
+ _pts[i].oldDegree = getPoint(i).totalDegree();
+ }
+
+ for (int i = 0; i < a->numberOfEdges(); i++)
+ {
+ eData[i].rdx = pData[getEdge(i).en].rx - pData[getEdge(i).st].rx;
+ eData[i].weight = 1;
+ _aretes[i].dx = eData[i].rdx;
+ }
+
+ SortPointsRounded ();
+
+ _need_edges_sorting = true;
+ GetWindings (this, nullptr, bool_op_union, true);
+
+// Plot(341,56,8,400,400,true,true,false,true);
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ swdData[i].leW %= 2;
+ swdData[i].riW %= 2;
+ if (swdData[i].leW < 0)
+ swdData[i].leW = -swdData[i].leW;
+ if (swdData[i].riW < 0)
+ swdData[i].riW = -swdData[i].riW;
+ if (swdData[i].leW > 0 && swdData[i].riW <= 0)
+ {
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW <= 0 && swdData[i].riW > 0)
+ {
+ Inverse (i);
+ eData[i].weight = 1;
+ }
+ else
+ {
+ eData[i].weight = 0;
+ SubEdge (i);
+ i--;
+ }
+ }
+
+ MakePointData (false);
+ MakeEdgeData (false);
+ MakeSweepDestData (false);
+
+ if (directedEulerian(this) == false)
+ {
+// printf( "pas euclidian2");
+ _pts.clear();
+ _aretes.clear();
+ return shape_euler_err;
+ }
+
+ type = shape_polygon;
+ return 0;
+}
+
+int
+Shape::ConvertToShape (Shape * a, FillRule directed, bool invert)
+{
+ // reset any existing stuff in this shape
+ Reset (0, 0);
+
+ // nothing to do with 0/1 points/edges
+ if (a->numberOfPoints() <= 1 || a->numberOfEdges() <= 1) {
+ return 0;
+ }
+
+ // if shape is not eulerian, we can't proceedA, why though you might ask?
+ // I think because if it's not eulerian, winding numbers won't be consistent and thus
+ // nothing else will work
+ if ( directed != fill_justDont && directedEulerian(a) == false ) {
+ g_warning ("Shape error in ConvertToShape: directedEulerian(a) == false\n");
+ return shape_input_err;
+ }
+
+ a->ResetSweep();
+
+ // allocating the sweepline data structures
+ if (sTree == nullptr) {
+ sTree = new SweepTreeList(a->numberOfEdges());
+ }
+ if (sEvts == nullptr) {
+ sEvts = new SweepEventQueue(a->numberOfEdges());
+ }
+
+ // make room for stuff and set flags
+ MakePointData(true);
+ MakeEdgeData(true);
+ MakeSweepSrcData(true);
+ MakeSweepDestData(true);
+ MakeBackData(a->_has_back_data);
+
+ // initialize pData and eData arrays, stores rounded points, rounded edge vectors and their lengths
+ a->initialisePointData();
+ a->initialiseEdgeData();
+
+ // sort points of a, top to bottom so we can sweepline
+ a->SortPointsRounded();
+
+ // clear the chgts array
+ chgts.clear();
+
+ double lastChange = a->pData[0].rx[1] - 1.0;
+ int lastChgtPt = 0;
+ int edgeHead = -1;
+ Shape *shapeHead = nullptr;
+
+ clearIncidenceData();
+
+ // index of the current point in shape a
+ int curAPt = 0;
+
+ // as long as there is a point we haven't seen yet or events that we haven't popped yet
+ while (curAPt < a->numberOfPoints() || sEvts->size() > 0) {
+ Geom::Point ptX;
+ double ptL, ptR;
+ SweepTree *intersL = nullptr;
+ SweepTree *intersR = nullptr;
+ int nPt = -1;
+ Shape *ptSh = nullptr;
+ bool isIntersection = false;
+
+ // this block gives us the earliest most point (sweeping top to bottom and left to right)
+ // whether it comes from the intersection event priority queue sEvts or sweepline list sTree.
+ // isIntersection tell us if it's coming from an intersection or from the endpoints list of shape a
+ // ptX contains the actual point itself
+ // ptSh contains the shape from which the point comes (if it does) (shape a always)
+ // nPt is the index of the point if it's coming from a shape
+
+ // is there an intersection event to pop?
+ if (sEvts->peek(intersL, intersR, ptX, ptL, ptR))
+ {
+ // is that intersection event before the current point in shape a? If yes, we pop and process the intersection event otherwise
+ // we process the point in shape a, whichever comes first (sweeping top to bottom) the one with smaller y or smaller x (if same y)
+ if (a->pData[curAPt].pending > 0
+ || (a->pData[curAPt].rx[1] > ptX[1]
+ || (a->pData[curAPt].rx[1] == ptX[1]
+ && a->pData[curAPt].rx[0] > ptX[0])))
+ {
+ // if yes, let's process the intersection point
+ /* FIXME: could just be pop? */
+ sEvts->extract(intersL, intersR, ptX, ptL, ptR);
+ isIntersection = true;
+ }
+ else // otherwise, we process the current point in shape a
+ {
+ nPt = curAPt++; // nPt stores the index of this point in shape a that we are going to process
+ ptSh = a;
+ ptX = ptSh->pData[nPt].rx; // get the rounded version of the current point in ptX
+ isIntersection = false; // not an intersection
+ }
+ }
+ else
+ {
+ nPt = curAPt++;
+ ptSh = a;
+ ptX = ptSh->pData[nPt].rx;
+ isIntersection = false;
+ }
+
+ if (isIntersection == false) // if this is not intersection event and the point has total degree of 0, we have nothing to do
+ {
+ if (ptSh->getPoint(nPt).dI == 0 && ptSh->getPoint(nPt).dO == 0)
+ continue;
+ }
+
+ // wherever the point comes from, we add the rounded version to "this" shape's list of points
+ Geom::Point rPtX;
+ rPtX[0]= Round (ptX[0]);
+ rPtX[1]= Round (ptX[1]);
+ int lastPointNo = AddPoint (rPtX); // lastPointNo is the index of this last rounded point we added
+ pData[lastPointNo].rx = rPtX;
+
+ // this whole block deals with the reconstruction procedure only do this if the y level
+ // changed, we don't need to do this as long as the y level has not changed, note that
+ // sweepline in this algorithm moves top to bottom but also left to right when there are
+ // multiple points at same y better to think of it as the sweepline being slightly slanted such
+ // that it'll hit the left points earlier than the right ones In fact, it's better to visualize
+ // as if we are iterating through set of points top to bottom and left ot right instead of a
+ // sweepline.
+ if (rPtX[1] > lastChange)
+ {
+ // the important thing this function does is that it sorts points and merges any duplicate points
+ // so edges with different points (which were at the same coordinates) would be forced to point
+ // to the same exact point. (useful for cases when multiple edges intersect at the same point)
+ // Sort all points before lastPointNo
+ int lastI = AssemblePoints (lastChgtPt, lastPointNo); // lastI is one more than the index of the last point that
+ // was added by AssemblePoints after sorting and merging
+
+ // after AssemblePoints is done sorting, the newInd variable holds the new index of that point
+
+ // update the leftRnd and rightRnd indexes to newInd while traversing the linked list of
+ // edges and shapes. leftRnd and rightRnd are the left most and right most points of an edge
+ // in the resultant polygon that intersect the sweepline. In all non-horizontal edges, both
+ // would be identical, only when the edge is horizontal, the two will be different since the
+ // sweepline will intersect it at multiple endpoints.
+ // To define it more strictly, you can think of leftRnd and rightRnd as being the left most
+ // and right most point in the final resulted shape ("this" shape) at the y level lastChange.
+ Shape *curSh = shapeHead;
+ int curBo = edgeHead;
+ while (curSh)
+ {
+ curSh->swsData[curBo].leftRnd =
+ pData[curSh->swsData[curBo].leftRnd].newInd;
+ curSh->swsData[curBo].rightRnd =
+ pData[curSh->swsData[curBo].rightRnd].newInd;
+
+ Shape *neSh = curSh->swsData[curBo].nextSh;
+ curBo = curSh->swsData[curBo].nextBo;
+ curSh = neSh;
+ }
+
+ for (auto & chgt : chgts)
+ {
+ chgt.ptNo = pData[chgt.ptNo].newInd; // this updates the ptNo index to the new index, so identical points really merge
+ if (chgt.type == 0)
+ {
+ if (chgt.src->getEdge(chgt.bord).st <
+ chgt.src->getEdge(chgt.bord).en)
+ {
+ chgt.src->swsData[chgt.bord].stPt = // <-- No idea where stPt and enPt are really used
+ chgt.ptNo;
+ }
+ else
+ {
+ chgt.src->swsData[chgt.bord].enPt =
+ chgt.ptNo;
+ }
+ }
+ else if (chgt.type == 1)
+ {
+ if (chgt.src->getEdge(chgt.bord).st >
+ chgt.src->getEdge(chgt.bord).en)
+ {
+ chgt.src->swsData[chgt.bord].stPt =
+ chgt.ptNo;
+ }
+ else
+ {
+ chgt.src->swsData[chgt.bord].enPt =
+ chgt.ptNo;
+ }
+ }
+ }
+
+ // finds if points at the y level "lastChange" lie on top of the edge and if yes, modifies
+ // leftRnd and rightRnd of those edges accordingly
+ CheckAdjacencies (lastI, lastChgtPt, shapeHead, edgeHead);
+
+ // reconstruct the edges
+ CheckEdges (lastI, lastChgtPt, a, nullptr, bool_op_union);
+
+ // for each one of the points in the range lastChgtPt..(lastI-1) and if there are already
+ // points associated to the edge pData[i].askForWindingB, push the current one (i) in the linked
+ // list
+ for (int i = lastChgtPt; i < lastI; i++) {
+ if (pData[i].askForWindingS) {
+ Shape *windS = pData[i].askForWindingS;
+ int windB = pData[i].askForWindingB;
+ pData[i].nextLinkedPoint = windS->swsData[windB].firstLinkedPoint;
+ windS->swsData[windB].firstLinkedPoint = i;
+ }
+ }
+
+ // note that AssemblePoints doesn't even touch lastPointNo, it iterates on all the points before
+ // lastPointNo, so while that range might have shrinked because of duplicate points, lastPointNo
+ // remains where it was, so we check if some points got merged, if yes, lastPointNo is kinda far away
+ // from those points (there are garbage points in between due to merging), so we drag it back
+ if (lastI < lastPointNo) {
+ _pts[lastI] = getPoint(lastPointNo);
+ pData[lastI] = pData[lastPointNo];
+ }
+ // set lastPointNo to lastI (the new index for lastPointNo)
+ lastPointNo = lastI;
+ _pts.resize(lastI + 1); // resize and delete everything beyond lastPointNo, we add 1 cuz lastI is an index so u
+ // add one to convert it to size
+
+ lastChgtPt = lastPointNo; // set lastChgtPt
+ lastChange = rPtX[1]; // set lastChange
+ chgts.clear(); // this chgts array gets cleared up whenever the y of the sweepline changes
+ edgeHead = -1;
+ shapeHead = nullptr;
+ }
+
+
+ // are we processing an intersection point?
+ if (isIntersection)
+ {
+ // printf("(%i %i [%i %i]) ",intersL->bord,intersR->bord,intersL->startPoint,intersR->startPoint);
+ // remove any intersections that have interesL as a RIGHT edge
+ intersL->RemoveEvent (*sEvts, LEFT);
+ // remove any intersections that have intersR as a LEFT edge
+ intersR->RemoveEvent (*sEvts, RIGHT);
+
+ // add the intersection point to the chgts array
+ AddChgt (lastPointNo, lastChgtPt, shapeHead, edgeHead, INTERSECTION,
+ intersL->src, intersL->bord, intersR->src, intersR->bord);
+
+ // swap the edges intersL and intersR with each other (because they swap their intersection point with the sweepline as
+ // you pass the intersection point)
+ intersL->SwapWithRight (*sTree, *sEvts);
+
+ // test intersection of the now left edge with the one on its left
+ TesteIntersection (intersL, LEFT, false);
+ // test intersection of the now right edge with the one on its right
+ TesteIntersection (intersR, RIGHT, false);
+ }
+ else
+ { // we are doing with a point in shape a (not an intersection point)
+ int cb;
+
+ // this whole block:
+ // - Counts how many edges start at the current point (nbDn)
+ // - Counts how many edges end at the current point (nbUp)
+ // - Notes the last edge that starts here (dnNo)
+ // - Notes the last edge that ends here (upNo)
+ int nbUp = 0, nbDn = 0;
+ int upNo = -1, dnNo = -1;
+ cb = ptSh->getPoint(nPt).incidentEdge[FIRST];
+ while (cb >= 0 && cb < ptSh->numberOfEdges())
+ {
+ if ((ptSh->getEdge(cb).st < ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).en)
+ || (ptSh->getEdge(cb).st > ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).st))
+ {
+ upNo = cb;
+ nbUp++;
+ }
+ if ((ptSh->getEdge(cb).st > ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).en)
+ || (ptSh->getEdge(cb).st < ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).st))
+ {
+ dnNo = cb;
+ nbDn++;
+ }
+ cb = ptSh->NextAt (nPt, cb);
+ }
+
+ if (nbDn <= 0)
+ {
+ upNo = -1;
+ }
+ if (upNo >= 0 && (SweepTree *) ptSh->swsData[upNo].misc == nullptr)
+ {
+ upNo = -1;
+ }
+
+ bool doWinding = true;
+
+ // these blocks of code do the job of adding/removing edges
+ // however, there are some optimizations which leads to their weird if blocks
+
+ // Is there any edge that ends here?
+ if (nbUp > 0)
+ {
+ cb = ptSh->getPoint(nPt).incidentEdge[FIRST];
+ // for all edges that connect to this point
+ while (cb >= 0 && cb < ptSh->numberOfEdges())
+ { // if the edge ends here
+ if ((ptSh->getEdge(cb).st < ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).en)
+ || (ptSh->getEdge(cb).st > ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).st))
+ {
+ if (cb != upNo) // if this is not the last edge that ended at this point
+ {
+ SweepTree *node =
+ (SweepTree *) ptSh->swsData[cb].misc; // get the sweepline node for this edge
+ if (node == nullptr)
+ {
+ }
+ else
+ {
+ AddChgt (lastPointNo, lastChgtPt, shapeHead, // add the corresponding remove event in chgts
+ edgeHead, EDGE_REMOVED, node->src, node->bord,
+ nullptr, -1);
+ ptSh->swsData[cb].misc = nullptr;
+
+ int onLeftB = -1, onRightB = -1;
+ Shape *onLeftS = nullptr;
+ Shape *onRightS = nullptr;
+ if (node->elem[LEFT])
+ {
+ onLeftB =
+ (static_cast <
+ SweepTree * >(node->elem[LEFT]))->bord;
+ onLeftS =
+ (static_cast <
+ SweepTree * >(node->elem[LEFT]))->src;
+ }
+ if (node->elem[RIGHT])
+ {
+ onRightB =
+ (static_cast <
+ SweepTree * >(node->elem[RIGHT]))->bord;
+ onRightS =
+ (static_cast <
+ SweepTree * >(node->elem[RIGHT]))->src;
+ }
+
+ node->Remove (*sTree, *sEvts, true); // remove this edge
+ // if there are edges on the left and right and they do not start or end at the current point
+ // test if they interesect with each other (since now this edge just go removed and they are side to side)
+ if (onLeftS && onRightS)
+ {
+ SweepTree *onLeft =
+ (SweepTree *) onLeftS->swsData[onLeftB].
+ misc;
+ if (onLeftS == ptSh
+ && (onLeftS->getEdge(onLeftB).en == nPt
+ || onLeftS->getEdge(onLeftB).st ==
+ nPt))
+ {
+ }
+ else
+ {
+ if (onRightS == ptSh
+ && (onRightS->getEdge(onRightB).en ==
+ nPt
+ || onRightS->getEdge(onRightB).
+ st == nPt))
+ {
+ }
+ else
+ {
+ TesteIntersection (onLeft, RIGHT, false);
+ }
+ }
+ }
+ }
+ }
+ }
+ cb = ptSh->NextAt (nPt, cb);
+ }
+ }
+
+ // traitement du "upNo devient dnNo"
+ SweepTree *insertionNode = nullptr;
+ if (dnNo >= 0) // if there is a last edge that started here
+ {
+ if (upNo >= 0) // and there is a last edge that ended here
+ {
+ SweepTree *node = (SweepTree *) ptSh->swsData[upNo].misc;
+
+ AddChgt (lastPointNo, lastChgtPt, shapeHead, edgeHead, EDGE_REMOVED, // add edge removal event to the list
+ node->src, node->bord, nullptr, -1);
+
+ ptSh->swsData[upNo].misc = nullptr;
+
+ node->RemoveEvents (*sEvts); // remove any events associated with this node
+ node->ConvertTo (ptSh, dnNo, 1, lastPointNo); // convert this node the last edge that got added at this point
+ ptSh->swsData[dnNo].misc = node; // store the sweepline edge tree node at misc for later use
+ TesteIntersection (node, RIGHT, false); // test the interesction of this node with the one on its right
+ TesteIntersection (node, LEFT, false); // test the interesection of this node with the one on its left
+ insertionNode = node; // a variable to keep the pointer to this node for later use
+
+ ptSh->swsData[dnNo].curPoint = lastPointNo; // mark the curPoint in swsData for later use in reconstruction
+ AddChgt (lastPointNo, lastChgtPt, shapeHead, edgeHead, EDGE_INSERTED,
+ node->src, node->bord, nullptr, -1); // add the edge insertion event to chgts
+ }
+ else // if there is a last edge that started at this point but not any that ended
+ {
+ SweepTree *node = sTree->add(ptSh, dnNo, 1, lastPointNo, this); // add this edge
+ ptSh->swsData[dnNo].misc = node; // store in misc too
+ node->Insert (*sTree, *sEvts, this, lastPointNo, true); // insert the node at its right location in the sweepline tree
+ if (doWinding)
+ {
+ SweepTree *myLeft =
+ static_cast < SweepTree * >(node->elem[LEFT]);
+ if (myLeft)
+ {
+ pData[lastPointNo].askForWindingS = myLeft->src;
+ pData[lastPointNo].askForWindingB = myLeft->bord;
+ }
+ else
+ {
+ pData[lastPointNo].askForWindingB = -1;
+ }
+ doWinding = false;
+ }
+ TesteIntersection (node, RIGHT, false); // test intersection of this newly inserted node with the one on its right
+ TesteIntersection (node, LEFT, false); // test intersection of this newly inserted node with the one on its left
+ insertionNode = node; // store insertionNode for later use
+
+ ptSh->swsData[dnNo].curPoint = lastPointNo; // mark the curPoint appropriately
+ AddChgt (lastPointNo, lastChgtPt, shapeHead, edgeHead, EDGE_INSERTED, // add the edge inserted event
+ node->src, node->bord, nullptr, -1);
+ }
+ }
+
+ if (nbDn > 1) // if there are more than 1 edges that start at this point
+ { // si nbDn == 1 , alors dnNo a deja ete traite
+ cb = ptSh->getPoint(nPt).incidentEdge[FIRST];
+ while (cb >= 0 && cb < ptSh->numberOfEdges()) // for all edges that connect to this point
+ {
+ if ((ptSh->getEdge(cb).st > ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).en)
+ || (ptSh->getEdge(cb).st < ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).st))
+ { // if the edge starts here
+ if (cb != dnNo)
+ {
+ SweepTree *node = sTree->add(ptSh, cb, 1, lastPointNo, this); // add the node to the tree
+ ptSh->swsData[cb].misc = node;
+ node->InsertAt (*sTree, *sEvts, this, insertionNode, // insert it at appropriate position
+ nPt, true);
+ if (doWinding)
+ {
+ SweepTree *myLeft =
+ static_cast < SweepTree * >(node->elem[LEFT]);
+ if (myLeft)
+ {
+ pData[lastPointNo].askForWindingS =
+ myLeft->src;
+ pData[lastPointNo].askForWindingB =
+ myLeft->bord;
+ }
+ else
+ {
+ pData[lastPointNo].askForWindingB = -1;
+ }
+ doWinding = false;
+ }
+ TesteIntersection (node, RIGHT, false); // test intersection of this edge with one on its left
+ TesteIntersection (node, LEFT, false); // test intersection of this edge with one on its right
+
+ ptSh->swsData[cb].curPoint = lastPointNo; // store curPoint in sws
+ AddChgt (lastPointNo, lastChgtPt, shapeHead, // add appropriate edge insertion event in chgts
+ edgeHead, EDGE_INSERTED, node->src, node->bord, nullptr,
+ -1);
+ }
+ }
+ cb = ptSh->NextAt (nPt, cb);
+ }
+ }
+ }
+ }
+ // a code block totally identical to the one found above in loop. Has to be run one last time
+ // so written outside..
+ {
+ int lastI = AssemblePoints (lastChgtPt, numberOfPoints());
+
+
+ Shape *curSh = shapeHead;
+ int curBo = edgeHead;
+ while (curSh)
+ {
+ curSh->swsData[curBo].leftRnd =
+ pData[curSh->swsData[curBo].leftRnd].newInd;
+ curSh->swsData[curBo].rightRnd =
+ pData[curSh->swsData[curBo].rightRnd].newInd;
+
+ Shape *neSh = curSh->swsData[curBo].nextSh;
+ curBo = curSh->swsData[curBo].nextBo;
+ curSh = neSh;
+ }
+
+ for (auto & chgt : chgts)
+ {
+ chgt.ptNo = pData[chgt.ptNo].newInd;
+ if (chgt.type == 0)
+ {
+ if (chgt.src->getEdge(chgt.bord).st <
+ chgt.src->getEdge(chgt.bord).en)
+ {
+ chgt.src->swsData[chgt.bord].stPt = chgt.ptNo;
+ }
+ else
+ {
+ chgt.src->swsData[chgt.bord].enPt = chgt.ptNo;
+ }
+ }
+ else if (chgt.type == 1)
+ {
+ if (chgt.src->getEdge(chgt.bord).st >
+ chgt.src->getEdge(chgt.bord).en)
+ {
+ chgt.src->swsData[chgt.bord].stPt = chgt.ptNo;
+ }
+ else
+ {
+ chgt.src->swsData[chgt.bord].enPt = chgt.ptNo;
+ }
+ }
+ }
+
+ CheckAdjacencies (lastI, lastChgtPt, shapeHead, edgeHead);
+
+ CheckEdges (lastI, lastChgtPt, a, nullptr, bool_op_union);
+
+ for (int i = lastChgtPt; i < lastI; i++)
+ {
+ if (pData[i].askForWindingS)
+ {
+ Shape *windS = pData[i].askForWindingS;
+ int windB = pData[i].askForWindingB;
+ pData[i].nextLinkedPoint = windS->swsData[windB].firstLinkedPoint;
+ windS->swsData[windB].firstLinkedPoint = i;
+ }
+ }
+
+ _pts.resize(lastI);
+
+ edgeHead = -1;
+ shapeHead = nullptr;
+ }
+
+ chgts.clear();
+
+ // Plot (98.0, 112.0, 8.0, 400.0, 400.0, true, true, true, true);
+ // Plot(200.0,200.0,2.0,400.0,400.0,true,true,true,true);
+
+ // AssemblePoints(a);
+
+ // GetAdjacencies(a);
+
+ // MakeAretes(a);
+ clearIncidenceData();
+
+ // deal with doublon edges (edges on top of each other)
+ // we only keep one edge and set its weight equivalent to the net difference of the edges.
+ // If two edges are exactly identical and in same direction their weights add up, if they
+ // are in the opposite direction, weights are subtracted. The other edges are removed.
+ AssembleAretes (directed);
+
+ // Plot (98.0, 112.0, 8.0, 400.0, 400.0, true, true, true, true);
+
+ // store the degrees at this point in time
+ for (int i = 0; i < numberOfPoints(); i++)
+ {
+ _pts[i].oldDegree = getPoint(i).totalDegree();
+ }
+ // Validate();
+
+ _need_edges_sorting = true;
+ if ( directed == fill_justDont ) {
+ SortEdges(); // sorting edges
+ } else {
+ GetWindings (a); // getting winding numbers of the edges
+ }
+ // Plot (98.0, 112.0, 8.0, 400.0, 400.0, true, true, true, true);
+ // if ( doDebug ) {
+ // a->CalcBBox();
+ // a->Plot(a->leftX,a->topY,32.0,0.0,0.0,true,true,true,true,"orig.svg");
+ // Plot(a->leftX,a->topY,32.0,0.0,0.0,true,true,true,true,"winded.svg");
+ // }
+
+ // change edges depending on the fill rule. Decide whether to keep it, invert it or get rid of it
+ if (directed == fill_positive)
+ {
+ if (invert)
+ {
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ if (swdData[i].leW < 0 && swdData[i].riW >= 0)
+ {
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW >= 0 && swdData[i].riW < 0)
+ {
+ Inverse (i);
+ eData[i].weight = 1;
+ }
+ else
+ {
+ eData[i].weight = 0;
+ SubEdge (i);
+ i--;
+ }
+ }
+ }
+ else
+ {
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ if (swdData[i].leW > 0 && swdData[i].riW <= 0)
+ {
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW <= 0 && swdData[i].riW > 0)
+ {
+ Inverse (i);
+ eData[i].weight = 1;
+ }
+ else
+ {
+ eData[i].weight = 0;
+ SubEdge (i);
+ i--;
+ }
+ }
+ }
+ }
+ else if (directed == fill_nonZero)
+ {
+ if (invert)
+ {
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ if (swdData[i].leW < 0 && swdData[i].riW == 0)
+ {
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW > 0 && swdData[i].riW == 0)
+ {
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW == 0 && swdData[i].riW < 0)
+ {
+ Inverse (i);
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW == 0 && swdData[i].riW > 0)
+ {
+ Inverse (i);
+ eData[i].weight = 1;
+ }
+ else
+ {
+ eData[i].weight = 0;
+ SubEdge (i);
+ i--;
+ }
+ }
+ }
+ else
+ {
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ if (swdData[i].leW > 0 && swdData[i].riW == 0)
+ {
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW < 0 && swdData[i].riW == 0)
+ {
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW == 0 && swdData[i].riW > 0)
+ {
+ Inverse (i);
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW == 0 && swdData[i].riW < 0)
+ {
+ Inverse (i);
+ eData[i].weight = 1;
+ }
+ else
+ {
+ eData[i].weight = 0;
+ SubEdge (i);
+ i--;
+ }
+ }
+ }
+ }
+ else if (directed == fill_oddEven)
+ {
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ swdData[i].leW %= 2;
+ swdData[i].riW %= 2;
+ if (swdData[i].leW < 0)
+ swdData[i].leW = -swdData[i].leW;
+ if (swdData[i].riW < 0)
+ swdData[i].riW = -swdData[i].riW;
+ if (swdData[i].leW > 0 && swdData[i].riW <= 0)
+ {
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW <= 0 && swdData[i].riW > 0)
+ {
+ Inverse (i);
+ eData[i].weight = 1;
+ }
+ else
+ {
+ eData[i].weight = 0;
+ SubEdge (i);
+ i--;
+ }
+ }
+ } else if ( directed == fill_justDont ) {
+ for (int i=0;i<numberOfEdges();i++) {
+ if ( getEdge(i).st < 0 || getEdge(i).en < 0 ) {
+ SubEdge(i);
+ i--;
+ } else {
+ eData[i].weight = 0;
+ }
+ }
+ }
+
+ // Plot(200.0,200.0,2.0,400.0,400.0,true,true,true,true);
+
+ delete sTree;
+ sTree = nullptr;
+ delete sEvts;
+ sEvts = nullptr;
+
+ MakePointData (false);
+ MakeEdgeData (false);
+ MakeSweepSrcData (false);
+ MakeSweepDestData (false);
+ a->CleanupSweep ();
+ type = shape_polygon;
+ return 0;
+}
+
+// technically it's just a ConvertToShape() on 2 polygons at the same time, and different rules
+// for choosing the edges according to their winding numbers.
+// probably one of the biggest function i ever wrote.
+int
+Shape::Booleen (Shape * a, Shape * b, BooleanOp mod,int cutPathID)
+{
+ if (a == b || a == nullptr || b == nullptr)
+ return shape_input_err;
+ Reset (0, 0);
+ if (a->numberOfPoints() <= 1 || a->numberOfEdges() <= 1)
+ return 0;
+ if (b->numberOfPoints() <= 1 || b->numberOfEdges() <= 1)
+ return 0;
+ if ( mod == bool_op_cut ) {
+ } else if ( mod == bool_op_slice ) {
+ } else {
+ if (a->type != shape_polygon)
+ return shape_input_err;
+ if (b->type != shape_polygon)
+ return shape_input_err;
+ }
+
+ a->ResetSweep ();
+ b->ResetSweep ();
+
+ if (sTree == nullptr) {
+ sTree = new SweepTreeList(a->numberOfEdges() + b->numberOfEdges());
+ }
+ if (sEvts == nullptr) {
+ sEvts = new SweepEventQueue(a->numberOfEdges() + b->numberOfEdges());
+ }
+
+ MakePointData (true);
+ MakeEdgeData (true);
+ MakeSweepSrcData (true);
+ MakeSweepDestData (true);
+ if (a->hasBackData () && b->hasBackData ())
+ {
+ MakeBackData (true);
+ }
+ else
+ {
+ MakeBackData (false);
+ }
+
+ a->initialisePointData();
+ b->initialisePointData();
+
+ a->initialiseEdgeData();
+ b->initialiseEdgeData();
+
+ a->SortPointsRounded ();
+ b->SortPointsRounded ();
+
+ chgts.clear();
+
+ double lastChange =
+ (a->pData[0].rx[1] <
+ b->pData[0].rx[1]) ? a->pData[0].rx[1] - 1.0 : b->pData[0].rx[1] - 1.0;
+ int lastChgtPt = 0;
+ int edgeHead = -1;
+ Shape *shapeHead = nullptr;
+
+ clearIncidenceData();
+
+ int curAPt = 0;
+ int curBPt = 0;
+
+ while (curAPt < a->numberOfPoints() || curBPt < b->numberOfPoints() || sEvts->size() > 0)
+ {
+/* for (int i=0;i<sEvts.nbEvt;i++) {
+ printf("%f %f %i %i\n",sEvts.events[i].posx,sEvts.events[i].posy,sEvts.events[i].leftSweep->bord,sEvts.events[i].rightSweep->bord); // localizing ok
+ }
+ // cout << endl;
+ if ( sTree.racine ) {
+ SweepTree* ct=static_cast <SweepTree*> (sTree.racine->Leftmost());
+ while ( ct ) {
+ printf("%i %i [%i\n",ct->bord,ct->startPoint,(ct->src==a)?1:0);
+ ct=static_cast <SweepTree*> (ct->elem[RIGHT]);
+ }
+ }
+ printf("\n");*/
+
+ Geom::Point ptX;
+ double ptL, ptR;
+ SweepTree *intersL = nullptr;
+ SweepTree *intersR = nullptr;
+ int nPt = -1;
+ Shape *ptSh = nullptr;
+ bool isIntersection = false;
+
+ if (sEvts->peek(intersL, intersR, ptX, ptL, ptR))
+ {
+ if (curAPt < a->numberOfPoints())
+ {
+ if (curBPt < b->numberOfPoints())
+ {
+ if (a->pData[curAPt].rx[1] < b->pData[curBPt].rx[1]
+ || (a->pData[curAPt].rx[1] == b->pData[curBPt].rx[1]
+ && a->pData[curAPt].rx[0] < b->pData[curBPt].rx[0]))
+ {
+ if (a->pData[curAPt].pending > 0
+ || (a->pData[curAPt].rx[1] > ptX[1]
+ || (a->pData[curAPt].rx[1] == ptX[1]
+ && a->pData[curAPt].rx[0] > ptX[0])))
+ {
+ /* FIXME: could be pop? */
+ sEvts->extract(intersL, intersR, ptX, ptL, ptR);
+ isIntersection = true;
+ }
+ else
+ {
+ nPt = curAPt++;
+ ptSh = a;
+ ptX = ptSh->pData[nPt].rx;
+ isIntersection = false;
+ }
+ }
+ else
+ {
+ if (b->pData[curBPt].pending > 0
+ || (b->pData[curBPt].rx[1] > ptX[1]
+ || (b->pData[curBPt].rx[1] == ptX[1]
+ && b->pData[curBPt].rx[0] > ptX[0])))
+ {
+ /* FIXME: could be pop? */
+ sEvts->extract(intersL, intersR, ptX, ptL, ptR);
+ isIntersection = true;
+ }
+ else
+ {
+ nPt = curBPt++;
+ ptSh = b;
+ ptX = ptSh->pData[nPt].rx;
+ isIntersection = false;
+ }
+ }
+ }
+ else
+ {
+ if (a->pData[curAPt].pending > 0
+ || (a->pData[curAPt].rx[1] > ptX[1]
+ || (a->pData[curAPt].rx[1] == ptX[1]
+ && a->pData[curAPt].rx[0] > ptX[0])))
+ {
+ /* FIXME: could be pop? */
+ sEvts->extract(intersL, intersR, ptX, ptL, ptR);
+ isIntersection = true;
+ }
+ else
+ {
+ nPt = curAPt++;
+ ptSh = a;
+ ptX = ptSh->pData[nPt].rx;
+ isIntersection = false;
+ }
+ }
+ }
+ else
+ {
+ if (b->pData[curBPt].pending > 0
+ || (b->pData[curBPt].rx[1] > ptX[1]
+ || (b->pData[curBPt].rx[1] == ptX[1]
+ && b->pData[curBPt].rx[0] > ptX[0])))
+ {
+ /* FIXME: could be pop? */
+ sEvts->extract(intersL, intersR, ptX, ptL, ptR);
+ isIntersection = true;
+ }
+ else
+ {
+ nPt = curBPt++;
+ ptSh = b;
+ ptX = ptSh->pData[nPt].rx;
+ isIntersection = false;
+ }
+ }
+ }
+ else
+ {
+ if (curAPt < a->numberOfPoints())
+ {
+ if (curBPt < b->numberOfPoints())
+ {
+ if (a->pData[curAPt].rx[1] < b->pData[curBPt].rx[1]
+ || (a->pData[curAPt].rx[1] == b->pData[curBPt].rx[1]
+ && a->pData[curAPt].rx[0] < b->pData[curBPt].rx[0]))
+ {
+ nPt = curAPt++;
+ ptSh = a;
+ }
+ else
+ {
+ nPt = curBPt++;
+ ptSh = b;
+ }
+ }
+ else
+ {
+ nPt = curAPt++;
+ ptSh = a;
+ }
+ }
+ else
+ {
+ nPt = curBPt++;
+ ptSh = b;
+ }
+ ptX = ptSh->pData[nPt].rx;
+ isIntersection = false;
+ }
+
+ if (isIntersection == false)
+ {
+ if (ptSh->getPoint(nPt).dI == 0 && ptSh->getPoint(nPt).dO == 0)
+ continue;
+ }
+
+ Geom::Point rPtX;
+ rPtX[0]= Round (ptX[0]);
+ rPtX[1]= Round (ptX[1]);
+ int lastPointNo = AddPoint (rPtX);
+ pData[lastPointNo].rx = rPtX;
+
+ if (rPtX[1] > lastChange)
+ {
+ int lastI = AssemblePoints (lastChgtPt, lastPointNo);
+
+
+ Shape *curSh = shapeHead;
+ int curBo = edgeHead;
+ while (curSh)
+ {
+ curSh->swsData[curBo].leftRnd =
+ pData[curSh->swsData[curBo].leftRnd].newInd;
+ curSh->swsData[curBo].rightRnd =
+ pData[curSh->swsData[curBo].rightRnd].newInd;
+
+ Shape *neSh = curSh->swsData[curBo].nextSh;
+ curBo = curSh->swsData[curBo].nextBo;
+ curSh = neSh;
+ }
+
+ for (auto & chgt : chgts)
+ {
+ chgt.ptNo = pData[chgt.ptNo].newInd;
+ if (chgt.type == 0)
+ {
+ if (chgt.src->getEdge(chgt.bord).st <
+ chgt.src->getEdge(chgt.bord).en)
+ {
+ chgt.src->swsData[chgt.bord].stPt =
+ chgt.ptNo;
+ }
+ else
+ {
+ chgt.src->swsData[chgt.bord].enPt =
+ chgt.ptNo;
+ }
+ }
+ else if (chgt.type == 1)
+ {
+ if (chgt.src->getEdge(chgt.bord).st >
+ chgt.src->getEdge(chgt.bord).en)
+ {
+ chgt.src->swsData[chgt.bord].stPt =
+ chgt.ptNo;
+ }
+ else
+ {
+ chgt.src->swsData[chgt.bord].enPt =
+ chgt.ptNo;
+ }
+ }
+ }
+
+ CheckAdjacencies (lastI, lastChgtPt, shapeHead, edgeHead);
+
+ CheckEdges (lastI, lastChgtPt, a, b, mod);
+
+ for (int i = lastChgtPt; i < lastI; i++)
+ {
+ if (pData[i].askForWindingS)
+ {
+ Shape *windS = pData[i].askForWindingS;
+ int windB = pData[i].askForWindingB;
+ pData[i].nextLinkedPoint =
+ windS->swsData[windB].firstLinkedPoint;
+ windS->swsData[windB].firstLinkedPoint = i;
+ }
+ }
+
+ if (lastI < lastPointNo)
+ {
+ _pts[lastI] = getPoint(lastPointNo);
+ pData[lastI] = pData[lastPointNo];
+ }
+ lastPointNo = lastI;
+ _pts.resize(lastI + 1);
+
+ lastChgtPt = lastPointNo;
+ lastChange = rPtX[1];
+ chgts.clear();
+ edgeHead = -1;
+ shapeHead = nullptr;
+ }
+
+
+ if (isIntersection)
+ {
+ // les 2 events de part et d'autre de l'intersection
+ // (celui de l'intersection a deja ete depile)
+ intersL->RemoveEvent (*sEvts, LEFT);
+ intersR->RemoveEvent (*sEvts, RIGHT);
+
+ AddChgt (lastPointNo, lastChgtPt, shapeHead, edgeHead, INTERSECTION,
+ intersL->src, intersL->bord, intersR->src, intersR->bord);
+
+ intersL->SwapWithRight (*sTree, *sEvts);
+
+ TesteIntersection (intersL, LEFT, true);
+ TesteIntersection (intersR, RIGHT, true);
+ }
+ else
+ {
+ int cb;
+
+ int nbUp = 0, nbDn = 0;
+ int upNo = -1, dnNo = -1;
+ cb = ptSh->getPoint(nPt).incidentEdge[FIRST];
+ while (cb >= 0 && cb < ptSh->numberOfEdges())
+ {
+ if ((ptSh->getEdge(cb).st < ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).en)
+ || (ptSh->getEdge(cb).st > ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).st))
+ {
+ upNo = cb;
+ nbUp++;
+ }
+ if ((ptSh->getEdge(cb).st > ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).en)
+ || (ptSh->getEdge(cb).st < ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).st))
+ {
+ dnNo = cb;
+ nbDn++;
+ }
+ cb = ptSh->NextAt (nPt, cb);
+ }
+
+ if (nbDn <= 0)
+ {
+ upNo = -1;
+ }
+ if (upNo >= 0 && (SweepTree *) ptSh->swsData[upNo].misc == nullptr)
+ {
+ upNo = -1;
+ }
+
+// upNo=-1;
+
+ bool doWinding = true;
+
+ if (nbUp > 0)
+ {
+ cb = ptSh->getPoint(nPt).incidentEdge[FIRST];
+ while (cb >= 0 && cb < ptSh->numberOfEdges())
+ {
+ if ((ptSh->getEdge(cb).st < ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).en)
+ || (ptSh->getEdge(cb).st > ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).st))
+ {
+ if (cb != upNo)
+ {
+ SweepTree *node =
+ (SweepTree *) ptSh->swsData[cb].misc;
+ if (node == nullptr)
+ {
+ }
+ else
+ {
+ AddChgt (lastPointNo, lastChgtPt, shapeHead,
+ edgeHead, EDGE_REMOVED, node->src, node->bord,
+ nullptr, -1);
+ ptSh->swsData[cb].misc = nullptr;
+
+ int onLeftB = -1, onRightB = -1;
+ Shape *onLeftS = nullptr;
+ Shape *onRightS = nullptr;
+ if (node->elem[LEFT])
+ {
+ onLeftB =
+ (static_cast <
+ SweepTree * >(node->elem[LEFT]))->bord;
+ onLeftS =
+ (static_cast <
+ SweepTree * >(node->elem[LEFT]))->src;
+ }
+ if (node->elem[RIGHT])
+ {
+ onRightB =
+ (static_cast <
+ SweepTree * >(node->elem[RIGHT]))->bord;
+ onRightS =
+ (static_cast <
+ SweepTree * >(node->elem[RIGHT]))->src;
+ }
+
+ node->Remove (*sTree, *sEvts, true);
+ if (onLeftS && onRightS)
+ {
+ SweepTree *onLeft =
+ (SweepTree *) onLeftS->swsData[onLeftB].
+ misc;
+// SweepTree* onRight=(SweepTree*)onRightS->swsData[onRightB].misc;
+ if (onLeftS == ptSh
+ && (onLeftS->getEdge(onLeftB).en == nPt
+ || onLeftS->getEdge(onLeftB).st ==
+ nPt))
+ {
+ }
+ else
+ {
+ if (onRightS == ptSh
+ && (onRightS->getEdge(onRightB).en ==
+ nPt
+ || onRightS->getEdge(onRightB).
+ st == nPt))
+ {
+ }
+ else
+ {
+ TesteIntersection (onLeft, RIGHT, true);
+ }
+ }
+ }
+ }
+ }
+ }
+ cb = ptSh->NextAt (nPt, cb);
+ }
+ }
+
+ // traitement du "upNo devient dnNo"
+ SweepTree *insertionNode = nullptr;
+ if (dnNo >= 0)
+ {
+ if (upNo >= 0)
+ {
+ SweepTree *node = (SweepTree *) ptSh->swsData[upNo].misc;
+
+ AddChgt (lastPointNo, lastChgtPt, shapeHead, edgeHead, EDGE_REMOVED,
+ node->src, node->bord, nullptr, -1);
+
+ ptSh->swsData[upNo].misc = nullptr;
+
+ node->RemoveEvents (*sEvts);
+ node->ConvertTo (ptSh, dnNo, 1, lastPointNo);
+ ptSh->swsData[dnNo].misc = node;
+ TesteIntersection (node, RIGHT, true);
+ TesteIntersection (node, LEFT, true);
+ insertionNode = node;
+
+ ptSh->swsData[dnNo].curPoint = lastPointNo;
+
+ AddChgt (lastPointNo, lastChgtPt, shapeHead, edgeHead, EDGE_INSERTED,
+ node->src, node->bord, nullptr, -1);
+ }
+ else
+ {
+ SweepTree *node = sTree->add(ptSh, dnNo, 1, lastPointNo, this);
+ ptSh->swsData[dnNo].misc = node;
+ node->Insert (*sTree, *sEvts, this, lastPointNo, true);
+
+ if (doWinding)
+ {
+ SweepTree *myLeft =
+ static_cast < SweepTree * >(node->elem[LEFT]);
+ if (myLeft)
+ {
+ pData[lastPointNo].askForWindingS = myLeft->src;
+ pData[lastPointNo].askForWindingB = myLeft->bord;
+ }
+ else
+ {
+ pData[lastPointNo].askForWindingB = -1;
+ }
+ doWinding = false;
+ }
+
+ TesteIntersection (node, RIGHT, true);
+ TesteIntersection (node, LEFT, true);
+ insertionNode = node;
+
+ ptSh->swsData[dnNo].curPoint = lastPointNo;
+
+ AddChgt (lastPointNo, lastChgtPt, shapeHead, edgeHead, EDGE_INSERTED,
+ node->src, node->bord, nullptr, -1);
+ }
+ }
+
+ if (nbDn > 1)
+ { // si nbDn == 1 , alors dnNo a deja ete traite
+ cb = ptSh->getPoint(nPt).incidentEdge[FIRST];
+ while (cb >= 0 && cb < ptSh->numberOfEdges())
+ {
+ if ((ptSh->getEdge(cb).st > ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).en)
+ || (ptSh->getEdge(cb).st < ptSh->getEdge(cb).en
+ && nPt == ptSh->getEdge(cb).st))
+ {
+ if (cb != dnNo)
+ {
+ SweepTree *node = sTree->add(ptSh, cb, 1, lastPointNo, this);
+ ptSh->swsData[cb].misc = node;
+// node->Insert(sTree,*sEvts,this,lastPointNo,true);
+ node->InsertAt (*sTree, *sEvts, this, insertionNode,
+ nPt, true);
+
+ if (doWinding)
+ {
+ SweepTree *myLeft =
+ static_cast < SweepTree * >(node->elem[LEFT]);
+ if (myLeft)
+ {
+ pData[lastPointNo].askForWindingS =
+ myLeft->src;
+ pData[lastPointNo].askForWindingB =
+ myLeft->bord;
+ }
+ else
+ {
+ pData[lastPointNo].askForWindingB = -1;
+ }
+ doWinding = false;
+ }
+
+ TesteIntersection (node, RIGHT, true);
+ TesteIntersection (node, LEFT, true);
+
+ ptSh->swsData[cb].curPoint = lastPointNo;
+
+ AddChgt (lastPointNo, lastChgtPt, shapeHead,
+ edgeHead, EDGE_INSERTED, node->src, node->bord, nullptr,
+ -1);
+ }
+ }
+ cb = ptSh->NextAt (nPt, cb);
+ }
+ }
+ }
+ }
+ {
+ int lastI = AssemblePoints (lastChgtPt, numberOfPoints());
+
+
+ Shape *curSh = shapeHead;
+ int curBo = edgeHead;
+ while (curSh)
+ {
+ curSh->swsData[curBo].leftRnd =
+ pData[curSh->swsData[curBo].leftRnd].newInd;
+ curSh->swsData[curBo].rightRnd =
+ pData[curSh->swsData[curBo].rightRnd].newInd;
+
+ Shape *neSh = curSh->swsData[curBo].nextSh;
+ curBo = curSh->swsData[curBo].nextBo;
+ curSh = neSh;
+ }
+
+ /* FIXME: this kind of code seems to appear frequently */
+ for (auto & chgt : chgts)
+ {
+ chgt.ptNo = pData[chgt.ptNo].newInd;
+ if (chgt.type == 0)
+ {
+ if (chgt.src->getEdge(chgt.bord).st <
+ chgt.src->getEdge(chgt.bord).en)
+ {
+ chgt.src->swsData[chgt.bord].stPt = chgt.ptNo;
+ }
+ else
+ {
+ chgt.src->swsData[chgt.bord].enPt = chgt.ptNo;
+ }
+ }
+ else if (chgt.type == 1)
+ {
+ if (chgt.src->getEdge(chgt.bord).st >
+ chgt.src->getEdge(chgt.bord).en)
+ {
+ chgt.src->swsData[chgt.bord].stPt = chgt.ptNo;
+ }
+ else
+ {
+ chgt.src->swsData[chgt.bord].enPt = chgt.ptNo;
+ }
+ }
+ }
+
+ CheckAdjacencies (lastI, lastChgtPt, shapeHead, edgeHead);
+
+ CheckEdges (lastI, lastChgtPt, a, b, mod);
+
+ for (int i = lastChgtPt; i < lastI; i++)
+ {
+ if (pData[i].askForWindingS)
+ {
+ Shape *windS = pData[i].askForWindingS;
+ int windB = pData[i].askForWindingB;
+ pData[i].nextLinkedPoint = windS->swsData[windB].firstLinkedPoint;
+ windS->swsData[windB].firstLinkedPoint = i;
+ }
+ }
+
+ _pts.resize(lastI);
+
+ edgeHead = -1;
+ shapeHead = nullptr;
+ }
+
+ chgts.clear();
+ clearIncidenceData();
+
+// Plot(190,70,6,400,400,true,false,true,true);
+
+ if ( mod == bool_op_cut ) {
+ AssembleAretes (fill_justDont);
+ // dupliquer les aretes de la coupure
+ int i=numberOfEdges()-1;
+ for (;i>=0;i--) {
+ if ( ebData[i].pathID == cutPathID ) {
+ // on duplique
+ int nEd=AddEdge(getEdge(i).en,getEdge(i).st);
+ ebData[nEd].pathID=cutPathID;
+ ebData[nEd].pieceID=ebData[i].pieceID;
+ ebData[nEd].tSt=ebData[i].tEn;
+ ebData[nEd].tEn=ebData[i].tSt;
+ eData[nEd].weight=eData[i].weight;
+ // lui donner les firstlinkedpoitn si besoin
+ if ( getEdge(i).en >= getEdge(i).st ) {
+ int cp = swsData[i].firstLinkedPoint;
+ while (cp >= 0) {
+ pData[cp].askForWindingB = nEd;
+ cp = pData[cp].nextLinkedPoint;
+ }
+ swsData[nEd].firstLinkedPoint = swsData[i].firstLinkedPoint;
+ swsData[i].firstLinkedPoint=-1;
+ }
+ }
+ }
+ } else if ( mod == bool_op_slice ) {
+ } else {
+ AssembleAretes ();
+ }
+
+ for (int i = 0; i < numberOfPoints(); i++)
+ {
+ _pts[i].oldDegree = getPoint(i).totalDegree();
+ }
+
+ _need_edges_sorting = true;
+ if ( mod == bool_op_slice ) {
+ } else {
+ GetWindings (a, b, mod, false);
+ }
+// Plot(190,70,6,400,400,true,true,true,true);
+
+ if (mod == bool_op_symdiff)
+ {
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ if (swdData[i].leW < 0)
+ swdData[i].leW = -swdData[i].leW;
+ if (swdData[i].riW < 0)
+ swdData[i].riW = -swdData[i].riW;
+
+ if (swdData[i].leW > 0 && swdData[i].riW <= 0)
+ {
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW <= 0 && swdData[i].riW > 0)
+ {
+ Inverse (i);
+ eData[i].weight = 1;
+ }
+ else
+ {
+ eData[i].weight = 0;
+ SubEdge (i);
+ i--;
+ }
+ }
+ }
+ else if (mod == bool_op_union || mod == bool_op_diff)
+ {
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ if (swdData[i].leW > 0 && swdData[i].riW <= 0)
+ {
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW <= 0 && swdData[i].riW > 0)
+ {
+ Inverse (i);
+ eData[i].weight = 1;
+ }
+ else
+ {
+ eData[i].weight = 0;
+ SubEdge (i);
+ i--;
+ }
+ }
+ }
+ else if (mod == bool_op_inters)
+ {
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ if (swdData[i].leW > 1 && swdData[i].riW <= 1)
+ {
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW <= 1 && swdData[i].riW > 1)
+ {
+ Inverse (i);
+ eData[i].weight = 1;
+ }
+ else
+ {
+ eData[i].weight = 0;
+ SubEdge (i);
+ i--;
+ }
+ }
+ } else if ( mod == bool_op_cut ) {
+ // inverser les aretes de la coupe au besoin
+ for (int i=0;i<numberOfEdges();i++) {
+ if ( getEdge(i).st < 0 || getEdge(i).en < 0 ) {
+ if ( i < numberOfEdges()-1 ) {
+ // decaler les askForWinding
+ int cp = swsData[numberOfEdges()-1].firstLinkedPoint;
+ while (cp >= 0) {
+ pData[cp].askForWindingB = i;
+ cp = pData[cp].nextLinkedPoint;
+ }
+ }
+ SwapEdges(i,numberOfEdges()-1);
+ SubEdge(numberOfEdges()-1);
+// SubEdge(i);
+ i--;
+ } else if ( ebData[i].pathID == cutPathID ) {
+ swdData[i].leW=swdData[i].leW%2;
+ swdData[i].riW=swdData[i].riW%2;
+ if ( swdData[i].leW < swdData[i].riW ) {
+ Inverse(i);
+ }
+ }
+ }
+ } else if ( mod == bool_op_slice ) {
+ // supprimer les aretes de la coupe
+ int i=numberOfEdges()-1;
+ for (;i>=0;i--) {
+ if ( ebData[i].pathID == cutPathID || getEdge(i).st < 0 || getEdge(i).en < 0 ) {
+ SubEdge(i);
+ }
+ }
+ }
+ else
+ {
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ if (swdData[i].leW > 0 && swdData[i].riW <= 0)
+ {
+ eData[i].weight = 1;
+ }
+ else if (swdData[i].leW <= 0 && swdData[i].riW > 0)
+ {
+ Inverse (i);
+ eData[i].weight = 1;
+ }
+ else
+ {
+ eData[i].weight = 0;
+ SubEdge (i);
+ i--;
+ }
+ }
+ }
+
+ delete sTree;
+ sTree = nullptr;
+ delete sEvts;
+ sEvts = nullptr;
+
+ if ( mod == bool_op_cut ) {
+ // on garde le askForWinding
+ } else {
+ MakePointData (false);
+ }
+ MakeEdgeData (false);
+ MakeSweepSrcData (false);
+ MakeSweepDestData (false);
+ a->CleanupSweep ();
+ b->CleanupSweep ();
+
+ if (directedEulerian(this) == false)
+ {
+// printf( "pas euclidian2");
+ _pts.clear();
+ _aretes.clear();
+ return shape_euler_err;
+ }
+ type = shape_polygon;
+ return 0;
+}
+
+// frontend to the TesteIntersection() below
+void Shape::TesteIntersection(SweepTree *t, Side s, bool onlyDiff)
+{
+ // get the element that is to the side s of node t
+ SweepTree *tt = static_cast<SweepTree*>(t->elem[s]);
+ if (tt == nullptr) {
+ return;
+ }
+
+ // set left right properly, a is left, b is right
+ SweepTree *a = (s == LEFT) ? tt : t;
+ SweepTree *b = (s == LEFT) ? t : tt;
+
+ // call the actual intersection checking function and if an intersection
+ // is detected, add it as an event
+ Geom::Point atx;
+ double atl;
+ double atr;
+ if (TesteIntersection(a, b, atx, atl, atr, onlyDiff)) {
+ sEvts->add(a, b, atx, atl, atr);
+ }
+}
+
+// a crucial piece of code: computing intersections between segments
+bool
+Shape::TesteIntersection (SweepTree * iL, SweepTree * iR, Geom::Point &atx, double &atL, double &atR, bool onlyDiff)
+{
+ // get the left edge's start and end point
+ int lSt = iL->src->getEdge(iL->bord).st, lEn = iL->src->getEdge(iL->bord).en;
+ // get the right edge's start and end point
+ int rSt = iR->src->getEdge(iR->bord).st, rEn = iR->src->getEdge(iR->bord).en;
+ // get both edge vectors
+ Geom::Point ldir, rdir;
+ ldir = iL->src->eData[iL->bord].rdx;
+ rdir = iR->src->eData[iR->bord].rdx;
+ // first, a round of checks to quickly dismiss edge which obviously dont intersect,
+ // such as having disjoint bounding boxes
+
+ // invert the edge vector and swap the endpoints if an edge is bottom to top
+ // or horizontal and right to left
+ if (lSt < lEn)
+ {
+ }
+ else
+ {
+ std::swap(lSt, lEn);
+ ldir = -ldir;
+ }
+ if (rSt < rEn)
+ {
+ }
+ else
+ {
+ std::swap(rSt, rEn);
+ rdir = -rdir;
+ }
+
+ // these blocks check if the bounding boxes of the two don't overlap, if they
+ // don't overlap, we can just return false since non-overlapping bounding boxes
+ // indicate they won't intersect
+ if (iL->src->pData[lSt].rx[0] < iL->src->pData[lEn].rx[0])
+ {
+ if (iR->src->pData[rSt].rx[0] < iR->src->pData[rEn].rx[0])
+ {
+ if (iL->src->pData[lSt].rx[0] > iR->src->pData[rEn].rx[0])
+ return false;
+ if (iL->src->pData[lEn].rx[0] < iR->src->pData[rSt].rx[0])
+ return false;
+ }
+ else
+ {
+ if (iL->src->pData[lSt].rx[0] > iR->src->pData[rSt].rx[0])
+ return false;
+ if (iL->src->pData[lEn].rx[0] < iR->src->pData[rEn].rx[0])
+ return false;
+ }
+ }
+ else
+ {
+ if (iR->src->pData[rSt].rx[0] < iR->src->pData[rEn].rx[0])
+ {
+ if (iL->src->pData[lEn].rx[0] > iR->src->pData[rEn].rx[0])
+ return false;
+ if (iL->src->pData[lSt].rx[0] < iR->src->pData[rSt].rx[0])
+ return false;
+ }
+ else
+ {
+ if (iL->src->pData[lEn].rx[0] > iR->src->pData[rSt].rx[0])
+ return false;
+ if (iL->src->pData[lSt].rx[0] < iR->src->pData[rEn].rx[0])
+ return false;
+ }
+ }
+
+ // see the second image in the header docs of this function to visualize
+ // this cross product
+ double ang = cross (ldir, rdir);
+ // ang*=iL->src->eData[iL->bord].isqlength;
+ // ang*=iR->src->eData[iR->bord].isqlength;
+ if (ang <= 0) return false; // edges in opposite directions: <-left ... right ->
+ // they can't intersect
+
+ // d'abord tester les bords qui partent d'un meme point
+ // if they come from same shape and they share the same start point
+ if (iL->src == iR->src && lSt == rSt)
+ {
+ // if they share the end point too, it's a doublon doesn't count as intersection
+ if (iL->src == iR->src && lEn == rEn)
+ return false; // c'est juste un doublon
+ // if we are here, it means they share the start point only and that counts as an interesection
+ // intersection point is the starting point and times are all set to -1
+ atx = iL->src->pData[lSt].rx;
+ atR = atL = -1;
+ return true; // l'ordre est mauvais
+ }
+ // if they only share the end points, doesn't count as intersection (no idea why)
+ // in my opinion, both endpoints shouldn't count for intersection
+ if (iL->src == iR->src && lEn == rEn)
+ return false; // rien a faire=ils vont terminer au meme endroit
+
+ // tester si on est dans une intersection multiple
+
+ // I'm not sure what onlyDiff does but it seems it stands for "only different", which means, the intersections
+ // will only be detected if the two edges are coming from different shapes, if they come from the same shape,
+ // don't do any checks, we are not interested. but this if statement should be somewhere above in the code
+ // not here, shouldn't it? Why bother doing the bounding box checks?
+ if (onlyDiff && iL->src == iR->src)
+ return false;
+
+ // on reprend les vrais points
+ // get the start end points again, since we might have swapped them above
+ lSt = iL->src->getEdge(iL->bord).st;
+ lEn = iL->src->getEdge(iL->bord).en;
+ rSt = iR->src->getEdge(iR->bord).st;
+ rEn = iR->src->getEdge(iR->bord).en;
+
+ // compute intersection (if there is one)
+ // Boissonat anr Preparata said in one paper that double precision floats were sufficient for get single precision
+ // coordinates for the intersection, if the endpoints are single precision. i hope they're right...
+ // so till here, lSt, lEn, rSt, rEn have been reset, but note that ldir and rdir are the same
+ {
+ Geom::Point sDiff, eDiff;
+ double slDot, elDot;
+ double srDot, erDot;
+ // a vector from the start point of right edge to the start point of left edge
+ sDiff = iL->src->pData[lSt].rx - iR->src->pData[rSt].rx;
+ // a vector from the start point of right edge to the end point of left edge
+ eDiff = iL->src->pData[lEn].rx - iR->src->pData[rSt].rx;
+ srDot = cross(rdir, sDiff);
+ erDot = cross(rdir, eDiff);
+ // a vector from the start point of left edge to the start point of right edge
+ sDiff = iR->src->pData[rSt].rx - iL->src->pData[lSt].rx;
+ // a vector from the start point of left edge to the end point of right edge
+ eDiff = iR->src->pData[rEn].rx - iL->src->pData[lSt].rx;
+ slDot = cross(ldir, sDiff);
+ elDot = cross(ldir, eDiff);
+ // these cross products above are shown in the third picture in the header docs of this function.
+ // The only thing that matters to us at the moment about these cross products is their sign
+ // not their value, the value comes in later. I've labelled the angle arcs with the name of the
+ // cross product so that you can immediately visualize the sign that the cross product will take
+ // take your right hand, index finger to first vector, middle finger to second vector, if thumb
+ // is into the page, cross is positive, else it's negative.
+
+ // basically these cross products give us a sense of where the endpoints of other vector is with
+ // respect to a particular vector. If both are on the opposite sides, it indicates that an intersection
+ // will happen. Of course you can have the edge far away and still have endpoints on opposite side,
+ // they won't intersect but those cases have already been ruled out above
+
+ // if both endpoints of left edge are on one side (the same side doesn't matter which one) of the right edge
+ if ((srDot >= 0 && erDot >= 0) || (srDot <= 0 && erDot <= 0))
+ {
+ // you might think okay if both endpoints of left edge are on same side of right edge, then they can't intersect
+ // right? no, they still can. An endpoint of the left edge can fall on the right edge and in that case
+ // there is an intersection
+ // the start point of the left edge is on the right edge
+ if (srDot == 0)
+ {
+ // this condition here is quite weird, due to it, some intersections won't get detected while others might, I
+ // don't really see why it has been done this way. See the fourth figure in the header docs of this function and
+ // you'll see both cases. One where the condition lSt < lEn is valid and an intersection is detected and another
+ // one where it isn't. In fact as I was testing this out, I realized the purpose of CheckAdjacencies. Apparently
+ // when a point of intersection is missed by this function, the edge still gets split up at the intersection point
+ // thanks to CheckAdjacencies. You can see this for yourself by taking a 1000 px by 1000 px canvas and the following
+ // SVG path: M 500,200 L 500,800 L 200,800 L 500,500 L 200,200 Z
+ // Try Path > Union with and without the CheckAdjacencies call and you'll see the difference in the resultant path.
+ // So I was trying to find out a case where this if statement lSt < lEn would be true and an intersection would be
+ // returned, I couldn't succeed at this. You can get lSt < lEn to be true, but something else above in the code will
+ // cause an early return, most likely the ang <= 0 condition. So in order words, I couldn't get the code below to
+ // run, ever.
+ if (lSt < lEn)
+ {
+ atx = iL->src->pData[lSt].rx;
+ atL = 0;
+ atR = slDot / (slDot - elDot);
+ return true;
+ }
+ else
+ {
+ return false;
+ }
+ }
+ else if (erDot == 0)
+ {
+ if (lSt > lEn)
+ {
+ atx = iL->src->pData[lEn].rx;
+ atL = 1;
+ atR = slDot / (slDot - elDot);
+ return true;
+ }
+ else
+ {
+ return false;
+ }
+ }
+ // This code doesn't make sense either, I couldn't get it to trigger
+ // TODO: Try again or just prove that it's impossible to reach here
+ if (srDot > 0 && erDot > 0)
+ {
+ if (rEn < rSt)
+ {
+ if (srDot < erDot)
+ {
+ if (lSt < lEn)
+ {
+ atx = iL->src->pData[lSt].rx;
+ atL = 0;
+ atR = slDot / (slDot - elDot);
+ return true;
+ }
+ }
+ else
+ {
+ if (lEn < lSt)
+ {
+ atx = iL->src->pData[lEn].rx;
+ atL = 1;
+ atR = slDot / (slDot - elDot);
+ return true;
+ }
+ }
+ }
+ }
+ if (srDot < 0 && erDot < 0)
+ {
+ if (rEn > rSt)
+ {
+ if (srDot > erDot)
+ {
+ if (lSt < lEn)
+ {
+ atx = iL->src->pData[lSt].rx;
+ atL = 0;
+ atR = slDot / (slDot - elDot);
+ return true;
+ }
+ }
+ else
+ {
+ if (lEn < lSt)
+ {
+ atx = iL->src->pData[lEn].rx;
+ atL = 1;
+ atR = slDot / (slDot - elDot);
+ return true;
+ }
+ }
+ }
+ }
+ return false;
+ }
+ // if both endpoints of the right edge are on the same side of left edge
+ if ((slDot >= 0 && elDot >= 0) || (slDot <= 0 && elDot <= 0))
+ {
+ if (slDot == 0)
+ {
+ if (rSt < rEn)
+ {
+ atx = iR->src->pData[rSt].rx;
+ atR = 0;
+ atL = srDot / (srDot - erDot);
+ return true;
+ }
+ else
+ {
+ return false;
+ }
+ }
+ else if (elDot == 0)
+ {
+ if (rSt > rEn)
+ {
+ atx = iR->src->pData[rEn].rx;
+ atR = 1;
+ atL = srDot / (srDot - erDot);
+ return true;
+ }
+ else
+ {
+ return false;
+ }
+ }
+ if (slDot > 0 && elDot > 0)
+ {
+ if (lEn > lSt)
+ {
+ if (slDot < elDot)
+ {
+ if (rSt < rEn)
+ {
+ atx = iR->src->pData[rSt].rx;
+ atR = 0;
+ atL = srDot / (srDot - erDot);
+ return true;
+ }
+ }
+ else
+ {
+ if (rEn < rSt)
+ {
+ atx = iR->src->pData[rEn].rx;
+ atR = 1;
+ atL = srDot / (srDot - erDot);
+ return true;
+ }
+ }
+ }
+ }
+ if (slDot < 0 && elDot < 0)
+ {
+ if (lEn < lSt)
+ {
+ if (slDot > elDot)
+ {
+ if (rSt < rEn)
+ {
+ atx = iR->src->pData[rSt].rx;
+ atR = 0;
+ atL = srDot / (srDot - erDot);
+ return true;
+ }
+ }
+ else
+ {
+ if (rEn < rSt)
+ {
+ atx = iR->src->pData[rEn].rx;
+ atR = 1;
+ atL = srDot / (srDot - erDot);
+ return true;
+ }
+ }
+ }
+ }
+ return false;
+ }
+
+ /* double slb=slDot-elDot,srb=srDot-erDot;
+ if ( slb < 0 ) slb=-slb;
+ if ( srb < 0 ) srb=-srb;*/
+ // We use different formulas depending on whose sin is greater
+
+ // These formulas would look really weird to you, but let's pick the first one
+ // and I'll do some maths that you can see in the header docs to elaborate what's
+ // happening
+ if (iL->src->eData[iL->bord].siEd > iR->src->eData[iR->bord].siEd)
+ {
+ atx =
+ (slDot * iR->src->pData[rEn].rx -
+ elDot * iR->src->pData[rSt].rx) / (slDot - elDot);
+ }
+ else
+ {
+ atx =
+ (srDot * iL->src->pData[lEn].rx -
+ erDot * iL->src->pData[lSt].rx) / (srDot - erDot);
+ }
+ atL = srDot / (srDot - erDot);
+ atR = slDot / (slDot - elDot);
+ return true;
+ }
+
+ return true;
+}
+
+int
+Shape::PushIncidence (Shape * a, int cb, int pt, double theta)
+{
+ if (theta < 0 || theta > 1)
+ return -1;
+
+ if (nbInc >= maxInc)
+ {
+ maxInc = 2 * nbInc + 1;
+ iData =
+ (incidenceData *) g_realloc(iData, maxInc * sizeof (incidenceData));
+ }
+ int n = nbInc++;
+ iData[n].nextInc = a->swsData[cb].firstLinkedPoint;
+ iData[n].pt = pt;
+ iData[n].theta = theta;
+ a->swsData[cb].firstLinkedPoint = n;
+ return n;
+}
+
+int
+Shape::CreateIncidence (Shape * a, int no, int nPt)
+{
+ Geom::Point adir, diff;
+ adir = a->eData[no].rdx;
+ diff = getPoint(nPt).x - a->pData[a->getEdge(no).st].rx;
+ double t = dot (diff, adir);
+ t *= a->eData[no].ilength;
+ return PushIncidence (a, no, nPt, t);
+}
+
+int
+Shape::Winding (int nPt) const
+{
+ // the array pData has a variable named askForWindingB
+ // that tells us which edge to go to to find the winding number
+ // of the pint nPt.
+ int askTo = pData[nPt].askForWindingB;
+ if (askTo < 0 || askTo >= numberOfEdges()) // if there is no info there, just return 0
+ return 0;
+ // if the edge is top to bottom, return left winding number otherwise the right winding number
+ // actually, while sweeping, ConvertToShape stores the edge on the immediate left of each point,
+ // hence, we are seeing the winding to the right of this edge and depending on orientation,
+ // right is "left" if edge is top to bottom, right is "right" if edge is bottom to top
+ if (getEdge(askTo).st < getEdge(askTo).en)
+ {
+ return swdData[askTo].leW;
+ }
+ else
+ {
+ return swdData[askTo].riW;
+ }
+ return 0;
+}
+
+int
+Shape::Winding (const Geom::Point px) const
+{
+ int lr = 0, ll = 0, rr = 0;
+
+ // for each edge
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ Geom::Point adir, diff, ast, aen;
+ adir = eData[i].rdx;
+
+ ast = pData[getEdge(i).st].rx; // start point of this edge
+ aen = pData[getEdge(i).en].rx; // end point of this edge
+
+ int nWeight = eData[i].weight; // weight of this edge
+
+ // this block checks if the vertical lines crossing the start and end points of the edge
+ // covers the point px or not. See the first figure in the header documentation to see
+ // what I mean. The figure shows two contours one inside another. It shows the point px
+ // and the current edge that the loop is processing is drawn in black color. Two dashed
+ // vertical lines create a region. This block of code checks if the point px lies within
+ // that region or not. Because if it doesn't, we really don't care about this edge at all
+ // then.
+ if (ast[0] < aen[0])
+ {
+ if (ast[0] > px[0])
+ continue;
+ if (aen[0] < px[0])
+ continue;
+ }
+ else
+ {
+ if (ast[0] < px[0])
+ continue;
+ if (aen[0] > px[0])
+ continue;
+ }
+
+ // the situations in these blocks are explained by the second and third figure in the header documentation
+ // the fourth figure along with the documentation there describe what ll and rr really do
+ if (ast[0] == px[0])
+ {
+ if (ast[1] >= px[1])
+ continue;
+ if (aen[0] == px[0])
+ continue;
+ if (aen[0] < px[0])
+ ll += nWeight;
+ else
+ rr -= nWeight;
+ continue;
+ }
+ if (aen[0] == px[0])
+ {
+ if (aen[1] >= px[1])
+ continue;
+ if (ast[0] == px[0])
+ continue;
+ if (ast[0] < px[0])
+ ll -= nWeight;
+ else
+ rr += nWeight;
+ continue;
+ }
+
+ // if the edge is below the point, it doesn't cut the ray at all
+ // so we don't care about it
+ if (ast[1] < aen[1])
+ {
+ if (ast[1] >= px[1])
+ continue;
+ }
+ else
+ {
+ if (aen[1] >= px[1])
+ continue;
+ }
+
+ // a vector from the edge start point to our point px whose winding we wanna calculate
+ diff = px - ast;
+ double cote = cross(adir, diff); // cross from edge vector to diff vector to figure out the orientation
+ if (cote == 0)
+ continue;
+ if (cote < 0)
+ {
+ if (ast[0] > px[0])
+ lr += nWeight;
+ }
+ else
+ {
+ if (ast[0] < px[0])
+ lr -= nWeight;
+ }
+ }
+ return lr + (ll + rr) / 2; // lr comes as it is, ll and rr get divided by two due to the reason I mention in the header file docs
+}
+
+// merging duplicate points and edges
+int
+Shape::AssemblePoints (int st, int en)
+{
+ if (en > st) {
+ for (int i = st; i < en; i++) pData[i].oldInd = i;
+// SortPoints(st,en-1);
+ SortPointsByOldInd (st, en - 1); // SortPointsByOldInd() is required here, because of the edges we have
+ // associated with the point for later computation of winding numbers.
+ // specifically, we need the first point we treated, it's the only one with a valid
+ // associated edge (man, that was a nice bug).
+ for (int i = st; i < en; i++) pData[pData[i].oldInd].newInd = i;
+
+ int lastI = st;
+ for (int i = st; i < en; i++) {
+ pData[i].pending = lastI++;
+ if (i > st && getPoint(i - 1).x[0] == getPoint(i).x[0] && getPoint(i - 1).x[1] == getPoint(i).x[1]) {
+ pData[i].pending = pData[i - 1].pending;
+ if (pData[pData[i].pending].askForWindingS == nullptr) {
+ pData[pData[i].pending].askForWindingS = pData[i].askForWindingS;
+ pData[pData[i].pending].askForWindingB = pData[i].askForWindingB;
+ } else {
+ if (pData[pData[i].pending].askForWindingS == pData[i].askForWindingS
+ && pData[pData[i].pending].askForWindingB == pData[i].askForWindingB) {
+ // meme bord, c bon
+ } else {
+ // meme point, mais pas le meme bord: ouille!
+ // il faut prendre le bord le plus a gauche
+ // en pratique, n'arrive que si 2 maxima sont dans la meme case -> le mauvais choix prend une arete incidente
+ // au bon choix
+// printf("doh");
+ }
+ }
+ lastI--;
+ } else {
+ if (i > pData[i].pending) {
+ _pts[pData[i].pending].x = getPoint(i).x;
+ pData[pData[i].pending].rx = getPoint(i).x;
+ pData[pData[i].pending].askForWindingS = pData[i].askForWindingS;
+ pData[pData[i].pending].askForWindingB = pData[i].askForWindingB;
+ }
+ }
+ }
+ for (int i = st; i < en; i++) pData[i].newInd = pData[pData[i].newInd].pending;
+ return lastI;
+ }
+ return en;
+}
+
+void
+Shape::AssemblePoints (Shape * a)
+{
+ if (hasPoints())
+ {
+ int lastI = AssemblePoints (0, numberOfPoints());
+
+ for (int i = 0; i < a->numberOfEdges(); i++)
+ {
+ a->swsData[i].stPt = pData[a->swsData[i].stPt].newInd;
+ a->swsData[i].enPt = pData[a->swsData[i].enPt].newInd;
+ }
+ for (int i = 0; i < nbInc; i++)
+ iData[i].pt = pData[iData[i].pt].newInd;
+
+ _pts.resize(lastI);
+ }
+}
+void
+Shape::AssembleAretes (FillRule directed)
+{
+ if ( directed == fill_justDont && _has_back_data == false ) {
+ directed=fill_nonZero;
+ }
+
+ // for each point in points
+ for (int i = 0; i < numberOfPoints(); i++) {
+ if (getPoint(i).totalDegree() == 2) { // if simple point with one incoming edge another outgoing edge
+ int cb, cc;
+ cb = getPoint(i).incidentEdge[FIRST]; // the first edge connected to the point
+ cc = getPoint(i).incidentEdge[LAST]; // the last edge connected to the point
+ bool doublon=false;
+ if ((getEdge(cb).st == getEdge(cc).st && getEdge(cb).en == getEdge(cc).en)
+ || (getEdge(cb).st == getEdge(cc).en && getEdge(cb).en == getEdge(cc).en)) doublon=true; // if the start and end edges have same endpoints, it's a doublon edge
+ if ( directed == fill_justDont ) {
+ if ( doublon ) {
+ // depending on pathID, pieceID and tSt reorient cb and cc if needed
+ if ( ebData[cb].pathID > ebData[cc].pathID ) {
+ cc = getPoint(i).incidentEdge[FIRST]; // on swappe pour enlever cc
+ cb = getPoint(i).incidentEdge[LAST];
+ } else if ( ebData[cb].pathID == ebData[cc].pathID ) {
+ if ( ebData[cb].pieceID > ebData[cc].pieceID ) {
+ cc = getPoint(i).incidentEdge[FIRST]; // on swappe pour enlever cc
+ cb = getPoint(i).incidentEdge[LAST];
+ } else if ( ebData[cb].pieceID == ebData[cc].pieceID ) {
+ if ( ebData[cb].tSt > ebData[cc].tSt ) {
+ cc = getPoint(i).incidentEdge[FIRST]; // on swappe pour enlever cc
+ cb = getPoint(i).incidentEdge[LAST];
+ }
+ }
+ }
+ }
+ if ( doublon ) eData[cc].weight = 0; // make cc's weight zero
+ } else {
+ }
+ if ( doublon ) {
+ if (getEdge(cb).st == getEdge(cc).st) { // if both edges share same start point
+ eData[cb].weight += eData[cc].weight; // you get double weight
+ } else {
+ eData[cb].weight -= eData[cc].weight; // if one's start is other's end, you subtract weight
+ }
+ eData[cc].weight = 0; // remove cc (set weight to zero)
+
+ // winding number seed stuff
+ if (swsData[cc].firstLinkedPoint >= 0) {
+ int cp = swsData[cc].firstLinkedPoint;
+ while (cp >= 0) {
+ pData[cp].askForWindingB = cb;
+ cp = pData[cp].nextLinkedPoint;
+ }
+ if (swsData[cb].firstLinkedPoint < 0) {
+ swsData[cb].firstLinkedPoint = swsData[cc].firstLinkedPoint;
+ } else {
+ int ncp = swsData[cb].firstLinkedPoint;
+ while (pData[ncp].nextLinkedPoint >= 0) {
+ ncp = pData[ncp].nextLinkedPoint;
+ }
+ pData[ncp].nextLinkedPoint = swsData[cc].firstLinkedPoint;
+ }
+ }
+
+ // disconnect start and end of cc
+ DisconnectStart (cc);
+ DisconnectEnd (cc);
+
+ if (numberOfEdges() > 1) {
+ int cp = swsData[numberOfEdges() - 1].firstLinkedPoint;
+ while (cp >= 0) {
+ pData[cp].askForWindingB = cc;
+ cp = pData[cp].nextLinkedPoint;
+ }
+ }
+ // swap cc with last edge
+ SwapEdges (cc, numberOfEdges() - 1);
+ if (cb == numberOfEdges() - 1) {
+ cb = cc;
+ }
+ // pop back the last one (to completely remove it from the array)
+ _aretes.pop_back();
+ }
+ } else {
+ int cb;
+ cb = getPoint(i).incidentEdge[FIRST];
+ while (cb >= 0 && cb < numberOfEdges()) {
+ int other = Other (i, cb);
+ int cc;
+ cc = getPoint(i).incidentEdge[FIRST];
+ while (cc >= 0 && cc < numberOfEdges()) {
+ int ncc = NextAt (i, cc);
+ bool doublon=false;
+ if (cc != cb && Other (i, cc) == other ) doublon=true;
+ if ( directed == fill_justDont ) {
+ if ( doublon ) {
+ if ( ebData[cb].pathID > ebData[cc].pathID ) {
+ doublon=false;
+ } else if ( ebData[cb].pathID == ebData[cc].pathID ) {
+ if ( ebData[cb].pieceID > ebData[cc].pieceID ) {
+ doublon=false;
+ } else if ( ebData[cb].pieceID == ebData[cc].pieceID ) {
+ if ( ebData[cb].tSt > ebData[cc].tSt ) {
+ doublon=false;
+ }
+ }
+ }
+ }
+ if ( doublon ) eData[cc].weight = 0;
+ } else {
+ }
+ if ( doublon ) {
+// if (cc != cb && Other (i, cc) == other) {
+ // doublon
+ if (getEdge(cb).st == getEdge(cc).st) {
+ eData[cb].weight += eData[cc].weight;
+ } else {
+ eData[cb].weight -= eData[cc].weight;
+ }
+ eData[cc].weight = 0;
+
+ if (swsData[cc].firstLinkedPoint >= 0) {
+ int cp = swsData[cc].firstLinkedPoint;
+ while (cp >= 0) {
+ pData[cp].askForWindingB = cb;
+ cp = pData[cp].nextLinkedPoint;
+ }
+ if (swsData[cb].firstLinkedPoint < 0) {
+ swsData[cb].firstLinkedPoint = swsData[cc].firstLinkedPoint;
+ } else {
+ int ncp = swsData[cb].firstLinkedPoint;
+ while (pData[ncp].nextLinkedPoint >= 0) {
+ ncp = pData[ncp].nextLinkedPoint;
+ }
+ pData[ncp].nextLinkedPoint = swsData[cc].firstLinkedPoint;
+ }
+ }
+
+ DisconnectStart (cc);
+ DisconnectEnd (cc);
+ if (numberOfEdges() > 1) {
+ int cp = swsData[numberOfEdges() - 1].firstLinkedPoint;
+ while (cp >= 0) {
+ pData[cp].askForWindingB = cc;
+ cp = pData[cp].nextLinkedPoint;
+ }
+ }
+ SwapEdges (cc, numberOfEdges() - 1);
+ if (cb == numberOfEdges() - 1) {
+ cb = cc;
+ }
+ if (ncc == numberOfEdges() - 1) {
+ ncc = cc;
+ }
+ _aretes.pop_back();
+ }
+ cc = ncc;
+ }
+ cb = NextAt (i, cb);
+ }
+ }
+ }
+
+ if ( directed == fill_justDont ) {
+ for (int i = 0; i < numberOfEdges(); i++) {
+ if (eData[i].weight == 0) {
+ // SubEdge(i);
+ // i--;
+ } else {
+ if (eData[i].weight < 0) Inverse (i);
+ }
+ }
+ } else {
+ for (int i = 0; i < numberOfEdges(); i++) {
+ if (eData[i].weight == 0) {
+ // SubEdge(i);
+ // i--;
+ } else {
+ if (eData[i].weight < 0) Inverse (i);
+ }
+ }
+ }
+ }
+void
+Shape::GetWindings (Shape * /*a*/, Shape * /*b*/, BooleanOp /*mod*/, bool brutal)
+{
+ // preparation du parcours
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ swdData[i].misc = nullptr;
+ swdData[i].precParc = swdData[i].suivParc = -1;
+ }
+
+ // we make sure that the edges are sorted. What this means is that for each point, all
+ // the edges that are attached to it are arranged in the linked list according to
+ // clockwise order (of their spatial orientation)
+ // chainage
+ SortEdges ();
+
+ int searchInd = 0;
+
+ int lastPtUsed = 0;
+ // okay now let's see what this outer most loop is supposed to do. Look, you can have a directed graph
+ // with multiple paths that don't touch each other. For example a rectangle inside another rectangle.
+ // If you just start at the first point and follow the edges moving around, you'd have explored one
+ // sub-graph but you wouldn't even touch the others. This outer loop ensures that all the points have
+ // been walked over. We start at the first point and start exploring. When we reach the end of that
+ // sub-graph, we update lastPtUsed and this outerloop will check if there are still points remaining
+ // to be explored, if yes, we start with the first point (that we haven't touched yet)
+ do
+ {
+ int startBord = -1;
+ int outsideW = 0; // the winding number outside (to the top left) of the first point in a sub-graph
+ {
+ int fi = 0;
+ // ignore all points that don't have any edges attached
+ for (fi = lastPtUsed; fi < numberOfPoints(); fi++)
+ {
+ if (getPoint(fi).incidentEdge[FIRST] >= 0 && swdData[getPoint(fi).incidentEdge[FIRST]].misc == nullptr)
+ break;
+ }
+ lastPtUsed = fi + 1;
+ if (fi < numberOfPoints())
+ {
+ // get the first edge attached to the first point
+ int bestB = getPoint(fi).incidentEdge[FIRST];
+ if (bestB >= 0)
+ {
+ // let's start with this edge
+ startBord = bestB;
+ // is the first point the first in the array? if yes, this ensure it's at the top most and left most position.
+ // Hence the winding number must be zero (since that region is literally outside everything)
+ if (fi == 0)
+ {
+ outsideW = 0;
+ }
+ else
+ {
+ // you can either compute the winding number by iterating through all the edges
+ // basically that would work by seeing how many edges a ray from (0, +infty) would cross
+ // and in which order
+ if (brutal)
+ {
+ outsideW = Winding (getPoint(fi).x);
+ }
+ // or we can get the winding number for that point computed by the sweepline.. this is pretty
+ // interesting.
+ else
+ {
+ outsideW = Winding (fi);
+ }
+ }
+ // TODO: Look at this piece
+ if ( getPoint(fi).totalDegree() == 1 ) {
+ if ( fi == getEdge(startBord).en ) {
+ if ( eData[startBord].weight == 0 ) {
+ // on se contente d'inverser
+ Inverse(startBord);
+ } else {
+ // on passe le askForWinding (sinon ca va rester startBord)
+ pData[getEdge(startBord).st].askForWindingB=pData[getEdge(startBord).en].askForWindingB;
+ }
+ }
+ }
+ if (getEdge(startBord).en == fi)
+ outsideW += eData[startBord].weight;
+ }
+ }
+ }
+ if (startBord >= 0)
+ {
+ // now start from this edge
+ // parcours en profondeur pour mettre les leF et riF a leurs valeurs
+ swdData[startBord].misc = (void *) 1;
+ // setting the winding numbers for this edge
+ // one question I had was, would these values for the first edge will always be valid?
+ // The answer is yes. Due to the fact that edges are sorted clockwise, and that
+ // we start with the top most (and leftmost if mutliple top most points exist), and that
+ // there is a piece of code above that adds weight to start edge if the edge ends at the current
+ // point, I think these will always be correct values.
+ swdData[startBord].leW = outsideW;
+ swdData[startBord].riW = outsideW - eData[startBord].weight;
+// if ( doDebug ) printf("part de %d\n",startBord);
+ // curBord is the current edge that we are at
+ int curBord = startBord;
+ // curDir is the direction, true means we are going in the direction of the edge vector, false means
+ // we are going in the direction opposite to the edge vector
+ bool curDir = true;
+ swdData[curBord].precParc = -1;
+ swdData[curBord].suivParc = -1;
+ // the depth first search
+ do
+ {
+ int cPt;
+ // if curDir is true, we are going along the edge, so get the end point
+ if (curDir)
+ cPt = getEdge(curBord).en;
+ else // if curDir is false, we are going opposite to the edge, so get the start point
+ cPt = getEdge(curBord).st;
+
+ // start finding the next edge to move to
+ int nb = curBord;
+// if ( doDebug ) printf("de curBord= %d avec leF= %d et riF= %d -> ",curBord,swdData[curBord].leW,swdData[curBord].riW);
+ do
+ {
+ int nnb = -1;
+ // see the diagram attached in the header file documentation of this function to see the
+ // four situations that can come up.
+ // outsideW here does not mean outside winding, in fact it means inside winding.
+ // if we are going along the edge, we save the right winding number for later use
+ if (getEdge(nb).en == cPt)
+ {
+ outsideW = swdData[nb].riW;
+ nnb = CyclePrevAt (cPt, nb); // get the prev edge, since sorting was clockwise, this means get the first counter-clockwise edge
+ }
+ // if we are going against the edge, we save it's left winding number for later use
+ else
+ {
+ outsideW = swdData[nb].leW;
+ nnb = CyclePrevAt (cPt, nb);
+ }
+ if (nnb == nb) // if we didn't get any "new" edge
+ {
+ // cul-de-sac
+ nb = -1;
+ break;
+ }
+ nb = nnb;
+ } // you can break for three reasons from this loop: having no other edge, we got the same one we started on, edge hasn't been visited yet
+ while (nb >= 0 && nb != curBord && swdData[nb].misc != nullptr);
+ // in the beginning, you'd break from the upper loop due to the misc condition and later on, you'll break due to nb != curBord which
+ // means we need to start backtracking
+ if (nb < 0 || nb == curBord) // backtracking block
+ {
+ // retour en arriere
+ // so if we are here, we couldn't get any new edge that we haven't seen yet
+ int oPt;
+ // we wanna find the previous point (since we are going back)
+ // if curDir is True, we were going along the edge, so get the start point (going backwards u see)
+ if (curDir)
+ oPt = getEdge(curBord).st;
+ else // if curDir is false, we were going against edge, so get the end point (going backwards)
+ oPt = getEdge(curBord).en;
+ curBord = swdData[curBord].precParc; // make current edge the previous one in traversal (back tracking)
+// if ( doDebug ) printf("retour vers %d\n",curBord);
+ if (curBord < 0) // if no edge to go back to, break
+ break;
+ if (oPt == getEdge(curBord).en) // if this new "current edge" ends at that point, curDir should be true, since we ideally have to go forward
+ curDir = true;
+ else // otherwise set it to false, so ideal direction would be against edge
+ curDir = false;
+ // I say ideal because this this is how backtracking is, if you have nothing new to go forward to, you go back once and see
+ // if there is another new edge to go forward to, if not you go back again, and you keep doing this until the point comes where
+ // you have nothing to go back to and then you break from the loop
+ }
+ else // okay we have new edge to compute windings
+ {
+ swdData[nb].misc = (void *) 1; // we visited this edge, so mark that
+ swdData[nb].ind = searchInd++; // probably for use later on?
+ if (cPt == getEdge(nb).st) // this outsideW is the winding stored before, see the diagram in header file
+ {
+ swdData[nb].riW = outsideW;
+ swdData[nb].leW = outsideW + eData[nb].weight;
+ }
+ else
+ {
+ swdData[nb].leW = outsideW;
+ swdData[nb].riW = outsideW - eData[nb].weight;
+ }
+ // maintaining the stack of traversal
+ swdData[nb].precParc = curBord;
+ swdData[curBord].suivParc = nb;
+ // this edge becomes current edge now
+ curBord = nb;
+// if ( doDebug ) printf("suite %d\n",curBord);
+ // set direction depending on how this edge is oriented
+ if (cPt == getEdge(nb).en)
+ curDir = false;
+ else
+ curDir = true;
+ }
+ }
+ while (true /*swdData[curBord].precParc >= 0 */ );
+ // fin du cas non-oriente
+ }
+ }
+ while (lastPtUsed < numberOfPoints());
+// fflush(stdout);
+}
+
+bool
+Shape::TesteIntersection (Shape * ils, Shape * irs, int ilb, int irb,
+ Geom::Point &atx, double &atL, double &atR,
+ bool /*onlyDiff*/)
+{
+ int lSt = ils->getEdge(ilb).st, lEn = ils->getEdge(ilb).en;
+ int rSt = irs->getEdge(irb).st, rEn = irs->getEdge(irb).en;
+ if (lSt == rSt || lSt == rEn)
+ {
+ return false;
+ }
+ if (lEn == rSt || lEn == rEn)
+ {
+ return false;
+ }
+
+ Geom::Point ldir, rdir;
+ ldir = ils->eData[ilb].rdx;
+ rdir = irs->eData[irb].rdx;
+
+ double il = ils->pData[lSt].rx[0], it = ils->pData[lSt].rx[1], ir =
+ ils->pData[lEn].rx[0], ib = ils->pData[lEn].rx[1];
+ if (il > ir)
+ {
+ std::swap(il, ir);
+ }
+ if (it > ib)
+ {
+ std::swap(it, ib);
+ }
+ double jl = irs->pData[rSt].rx[0], jt = irs->pData[rSt].rx[1], jr =
+ irs->pData[rEn].rx[0], jb = irs->pData[rEn].rx[1];
+ if (jl > jr)
+ {
+ std::swap(jl, jr);
+ }
+ if (jt > jb)
+ {
+ std::swap(jt, jb);
+ }
+
+ if (il > jr || it > jb || ir < jl || ib < jt)
+ return false;
+
+ // pre-test
+ {
+ Geom::Point sDiff, eDiff;
+ double slDot, elDot;
+ double srDot, erDot;
+ sDiff = ils->pData[lSt].rx - irs->pData[rSt].rx;
+ eDiff = ils->pData[lEn].rx - irs->pData[rSt].rx;
+ srDot = cross(rdir, sDiff);
+ erDot = cross(rdir, eDiff);
+ if ((srDot >= 0 && erDot >= 0) || (srDot <= 0 && erDot <= 0))
+ return false;
+
+ sDiff = irs->pData[rSt].rx - ils->pData[lSt].rx;
+ eDiff = irs->pData[rEn].rx - ils->pData[lSt].rx;
+ slDot = cross(ldir, sDiff);
+ elDot = cross(ldir, eDiff);
+ if ((slDot >= 0 && elDot >= 0) || (slDot <= 0 && elDot <= 0))
+ return false;
+
+ double slb = slDot - elDot, srb = srDot - erDot;
+ if (slb < 0)
+ slb = -slb;
+ if (srb < 0)
+ srb = -srb;
+ if (slb > srb)
+ {
+ atx =
+ (slDot * irs->pData[rEn].rx - elDot * irs->pData[rSt].rx) / (slDot -
+ elDot);
+ }
+ else
+ {
+ atx =
+ (srDot * ils->pData[lEn].rx - erDot * ils->pData[lSt].rx) / (srDot -
+ erDot);
+ }
+ atL = srDot / (srDot - erDot);
+ atR = slDot / (slDot - elDot);
+ return true;
+ }
+
+ // a mettre en double precision pour des resultats exacts
+ Geom::Point usvs;
+ usvs = irs->pData[rSt].rx - ils->pData[lSt].rx;
+
+ // pas sur de l'ordre des coefs de m
+ Geom::Affine m(ldir[0], ldir[1],
+ rdir[0], rdir[1],
+ 0, 0);
+ double det = m.det();
+
+ double tdet = det * ils->eData[ilb].isqlength * irs->eData[irb].isqlength;
+
+ if (tdet > -0.0001 && tdet < 0.0001)
+ { // ces couillons de vecteurs sont colineaires
+ Geom::Point sDiff, eDiff;
+ double sDot, eDot;
+ sDiff = ils->pData[lSt].rx - irs->pData[rSt].rx;
+ eDiff = ils->pData[lEn].rx - irs->pData[rSt].rx;
+ sDot = cross(rdir, sDiff);
+ eDot = cross(rdir, eDiff);
+
+ atx =
+ (sDot * irs->pData[lEn].rx - eDot * irs->pData[lSt].rx) / (sDot -
+ eDot);
+ atL = sDot / (sDot - eDot);
+
+ sDiff = irs->pData[rSt].rx - ils->pData[lSt].rx;
+ eDiff = irs->pData[rEn].rx - ils->pData[lSt].rx;
+ sDot = cross(ldir, sDiff);
+ eDot = cross(ldir, eDiff);
+
+ atR = sDot / (sDot - eDot);
+
+ return true;
+ }
+
+ // plus de colinearite ni d'extremites en commun
+ m[1] = -m[1];
+ m[2] = -m[2];
+ {
+ double swap = m[0];
+ m[0] = m[3];
+ m[3] = swap;
+ }
+
+ atL = (m[0]* usvs[0] + m[1] * usvs[1]) / det;
+ atR = -(m[2] * usvs[0] + m[3] * usvs[1]) / det;
+ atx = ils->pData[lSt].rx + atL * ldir;
+
+
+ return true;
+}
+
+bool
+Shape::TesteAdjacency (Shape * a, int no, const Geom::Point atx, int nPt,
+ bool push)
+{
+ if (nPt == a->swsData[no].stPt || nPt == a->swsData[no].enPt)
+ return false;
+
+ Geom::Point adir, diff, ast, aen, diff1, diff2, diff3, diff4;
+
+ ast = a->pData[a->getEdge(no).st].rx;
+ aen = a->pData[a->getEdge(no).en].rx;
+
+ adir = a->eData[no].rdx;
+
+ double sle = a->eData[no].length;
+ double ile = a->eData[no].ilength;
+
+ diff = atx - ast;
+
+ double e = IHalfRound(cross(adir, diff) * a->eData[no].isqlength);
+ if (-3 < e && e < 3)
+ {
+ double rad = HalfRound (0.501); // when using single precision, 0.505 is better (0.5 would be the correct value,
+ // but it produces lots of bugs)
+ diff1[0] = diff[0] - rad;
+ diff1[1] = diff[1] - rad;
+ diff2[0] = diff[0] + rad;
+ diff2[1] = diff[1] - rad;
+ diff3[0] = diff[0] + rad;
+ diff3[1] = diff[1] + rad;
+ diff4[0] = diff[0] - rad;
+ diff4[1] = diff[1] + rad;
+ double di1, di2;
+ bool adjacent = false;
+ di1 = cross(adir, diff1);
+ di2 = cross(adir, diff3);
+ if ((di1 < 0 && di2 > 0) || (di1 > 0 && di2 < 0))
+ {
+ adjacent = true;
+ }
+ else
+ {
+ di1 = cross(adir, diff2);
+ di2 = cross(adir, diff4);
+ if ((di1 < 0 && di2 > 0) || (di1 > 0 && di2 < 0))
+ {
+ adjacent = true;
+ }
+ }
+ if (adjacent)
+ {
+ double t = dot (diff, adir);
+ if (t > 0 && t < sle)
+ {
+ if (push)
+ {
+ t *= ile;
+ PushIncidence (a, no, nPt, t);
+ }
+ return true;
+ }
+ }
+ }
+ return false;
+}
+
+void
+Shape::CheckAdjacencies (int lastPointNo, int lastChgtPt, Shape * /*shapeHead*/,
+ int /*edgeHead*/)
+{
+ // for each event in chgts
+ for (auto & chgt : chgts)
+ {
+ // get the chgt.ptoNo, which is the point at which the event happened
+ int chLeN = chgt.ptNo;
+ int chRiN = chgt.ptNo;
+ if (chgt.src)
+ {
+ Shape *lS = chgt.src;
+ int lB = chgt.bord;
+ // get the leftRnd and rightRnd of this edge
+ int lftN = lS->swsData[lB].leftRnd;
+ int rgtN = lS->swsData[lB].rightRnd;
+ // expand the range chLeN..chRiN
+ if (lftN < chLeN)
+ chLeN = lftN;
+ if (rgtN > chRiN)
+ chRiN = rgtN;
+ // check each point from lastChgtPt to leftN-1 for a possible adjacency with
+ // the edge, if detected mark it by modifying leftRnd
+ // Note we do this in reverse order by starting at the point closer to the
+ // edge first. If an adjacency is not detected, we immediately break since
+ // if a point is not adjacent, another on its left won't be adjacent either
+// for (int n=lftN;n<=rgtN;n++) CreateIncidence(lS,lB,n);
+ for (int n = lftN - 1; n >= lastChgtPt; n--)
+ {
+ if (TesteAdjacency (lS, lB, getPoint(n).x, n, false) ==
+ false)
+ break;
+ lS->swsData[lB].leftRnd = n;
+ }
+ // check each point from rgtN+1 to lastPointNo (not included) for a possible adjacency with
+ // the edge, if detected mark it by modifying rightRnd
+ // If an adjacency is not detected, we immediately break since if a point
+ // is not adjacent, another one to its right won't be either.
+ for (int n = rgtN + 1; n < lastPointNo; n++)
+ {
+ if (TesteAdjacency (lS, lB, getPoint(n).x, n, false) ==
+ false)
+ break;
+ lS->swsData[lB].rightRnd = n;
+ }
+ }
+ // totally identical to the block above
+ if (chgt.osrc)
+ {
+ Shape *rS = chgt.osrc;
+ int rB = chgt.obord;
+ int lftN = rS->swsData[rB].leftRnd;
+ int rgtN = rS->swsData[rB].rightRnd;
+ if (lftN < chLeN)
+ chLeN = lftN;
+ if (rgtN > chRiN)
+ chRiN = rgtN;
+// for (int n=lftN;n<=rgtN;n++) CreateIncidence(rS,rB,n);
+ for (int n = lftN - 1; n >= lastChgtPt; n--)
+ {
+ if (TesteAdjacency (rS, rB, getPoint(n).x, n, false) ==
+ false)
+ break;
+ rS->swsData[rB].leftRnd = n;
+ }
+ for (int n = rgtN + 1; n < lastPointNo; n++)
+ {
+ if (TesteAdjacency (rS, rB, getPoint(n).x, n, false) ==
+ false)
+ break;
+ rS->swsData[rB].rightRnd = n;
+ }
+ }
+ // very interesting part, deals with edges to the left in the sweepline at the time
+ // the event took place
+ if (chgt.lSrc)
+ {
+ // is the left edge's leftRnd smaller than lastChgtPt, basically this is a way to check
+ // if leftRnd got updated in the previous iteration of the main loop of Shape::ConvertToShape
+ // or not.
+ if (chgt.lSrc->swsData[chgt.lBrd].leftRnd < lastChgtPt)
+ {
+ // get the left edge and its shape
+ Shape *nSrc = chgt.lSrc;
+ int nBrd = chgt.lBrd /*,nNo=chgts[cCh].ptNo */ ;
+ bool hit;
+
+ // iterate through the linked list of edges to the left
+ do
+ {
+ hit = false; // adjacency got detected?
+ // check all points from chRiN to chLeN
+ // we go right to left
+ for (int n = chRiN; n >= chLeN; n--)
+ {
+ // test if the point is adjacent to the edge
+ if (TesteAdjacency
+ (nSrc, nBrd, getPoint(n).x, n, false))
+ {
+ // has the leftRnd been updated in previous iteration? if no? set it directly
+ if (nSrc->swsData[nBrd].leftRnd < lastChgtPt)
+ {
+ nSrc->swsData[nBrd].leftRnd = n;
+ nSrc->swsData[nBrd].rightRnd = n;
+ }
+ else // if yes, we do some checking and only update if it expands the span
+ {
+ if (n < nSrc->swsData[nBrd].leftRnd)
+ nSrc->swsData[nBrd].leftRnd = n;
+ if (n > nSrc->swsData[nBrd].rightRnd)
+ nSrc->swsData[nBrd].rightRnd = n;
+ }
+ hit = true;
+ }
+ }
+ // test all points between lastChgtPt and chLeN - 1
+ for (int n = chLeN - 1; n >= lastChgtPt; n--)
+ {
+ if (TesteAdjacency
+ (nSrc, nBrd, getPoint(n).x, n, false) == false)
+ break;
+ if (nSrc->swsData[nBrd].leftRnd < lastChgtPt)
+ {
+ nSrc->swsData[nBrd].leftRnd = n;
+ nSrc->swsData[nBrd].rightRnd = n;
+ }
+ else
+ {
+ if (n < nSrc->swsData[nBrd].leftRnd)
+ nSrc->swsData[nBrd].leftRnd = n;
+ if (n > nSrc->swsData[nBrd].rightRnd)
+ nSrc->swsData[nBrd].rightRnd = n;
+ }
+ hit = true;
+ }
+ // if no adjacency got detected, no point in going further left so break, if yes
+ // we continue and see if we can repeat the process on the edge to the left
+ // and so on (basically going left detecting adjacencies)
+ if (hit)
+ {
+ // get the edge on the left, if non exist, break
+ SweepTree *node =
+ static_cast < SweepTree * >(nSrc->swsData[nBrd].misc);
+ if (node == nullptr)
+ break;
+ node = static_cast < SweepTree * >(node->elem[LEFT]);
+ if (node == nullptr)
+ break;
+ nSrc = node->src;
+ nBrd = node->bord;
+ // the edge on the left, did its leftRnd update in the previous iteration of the main loop if ConvertToShape?
+ if (nSrc->swsData[nBrd].leftRnd >= lastChgtPt)
+ break;
+ }
+ }
+ while (hit);
+
+ }
+ }
+ // same thing but to the right side?
+ if (chgt.rSrc)
+ {
+ if (chgt.rSrc->swsData[chgt.rBrd].leftRnd < lastChgtPt)
+ {
+ Shape *nSrc = chgt.rSrc;
+ int nBrd = chgt.rBrd /*,nNo=chgts[cCh].ptNo */ ;
+ bool hit;
+ do
+ {
+ hit = false;
+ // test points between chLeN and chRiN for adjacency
+ // but go left to right
+ for (int n = chLeN; n <= chRiN; n++)
+ {
+ if (TesteAdjacency
+ (nSrc, nBrd, getPoint(n).x, n, false))
+ {
+ if (nSrc->swsData[nBrd].leftRnd < lastChgtPt)
+ {
+ nSrc->swsData[nBrd].leftRnd = n;
+ nSrc->swsData[nBrd].rightRnd = n;
+ }
+ else
+ {
+ if (n < nSrc->swsData[nBrd].leftRnd)
+ nSrc->swsData[nBrd].leftRnd = n;
+ if (n > nSrc->swsData[nBrd].rightRnd)
+ nSrc->swsData[nBrd].rightRnd = n;
+ }
+ hit = true;
+ }
+ }
+ // testing points between chRiN and lastPointNo for adjacency
+ for (int n = chRiN + 1; n < lastPointNo; n++)
+ {
+ if (TesteAdjacency
+ (nSrc, nBrd, getPoint(n).x, n, false) == false)
+ break;
+ if (nSrc->swsData[nBrd].leftRnd < lastChgtPt)
+ {
+ nSrc->swsData[nBrd].leftRnd = n;
+ nSrc->swsData[nBrd].rightRnd = n;
+ }
+ else
+ {
+ if (n < nSrc->swsData[nBrd].leftRnd)
+ nSrc->swsData[nBrd].leftRnd = n;
+ if (n > nSrc->swsData[nBrd].rightRnd)
+ nSrc->swsData[nBrd].rightRnd = n;
+ }
+ hit = true;
+ }
+ if (hit)
+ {
+ SweepTree *node =
+ static_cast < SweepTree * >(nSrc->swsData[nBrd].misc);
+ if (node == nullptr)
+ break;
+ node = static_cast < SweepTree * >(node->elem[RIGHT]);
+ if (node == nullptr)
+ break;
+ nSrc = node->src;
+ nBrd = node->bord;
+ if (nSrc->swsData[nBrd].leftRnd >= lastChgtPt)
+ break;
+ }
+ }
+ while (hit);
+ }
+ }
+ }
+}
+
+
+void Shape::AddChgt(int lastPointNo, int lastChgtPt, Shape * &shapeHead,
+ int &edgeHead, sTreeChangeType type, Shape * lS, int lB, Shape * rS,
+ int rB)
+{
+ // fill in the event details and push it
+ sTreeChange c;
+ c.ptNo = lastPointNo;
+ c.type = type;
+ c.src = lS;
+ c.bord = lB;
+ c.osrc = rS;
+ c.obord = rB;
+ chgts.push_back(c);
+ // index of the newly added event
+ const int nCh = chgts.size() - 1;
+
+ /* FIXME: this looks like a cut and paste job */
+
+ if (lS) {
+ // if there is an edge to the left, mark it in lSrc
+ SweepTree *lE = static_cast < SweepTree * >(lS->swsData[lB].misc);
+ if (lE && lE->elem[LEFT]) {
+ SweepTree *llE = static_cast < SweepTree * >(lE->elem[LEFT]);
+ chgts[nCh].lSrc = llE->src;
+ chgts[nCh].lBrd = llE->bord;
+ } else {
+ chgts[nCh].lSrc = nullptr;
+ chgts[nCh].lBrd = -1;
+ }
+
+ // lastChgtPt is same as lastPointNo if lastPointNo is the leftmost point in that y level and it's the
+ // left most point on the y level of lastPointNo otherwise
+ // leftRnd will be smaller than lastChgtPt if the last time the edge participated in any event (edge addition/intersection)
+ // was before lastChgtPt.
+ if (lS->swsData[lB].leftRnd < lastChgtPt) {
+ lS->swsData[lB].leftRnd = lastPointNo; // set leftRnd to the current point
+ lS->swsData[lB].nextSh = shapeHead; // add this edge in the linked list
+ lS->swsData[lB].nextBo = edgeHead;
+ edgeHead = lB;
+ shapeHead = lS;
+ } else { // If an event occured to the edge after lastChgtPt (which is possible, for example, a horizontal edge
+ // that intersects with other edges.
+ // get the leftRnd already
+ int old = lS->swsData[lB].leftRnd;
+ // This seems really weird. I suspect this if statement will never be true in a top to bottom sweepline
+ // see if we reached this point, it means old >= lastChgtPt
+ // and lastChgtPt is the leftmost point at the current y level of lastPointNo
+ // so how can old have an x greater than lastPoint? The sweepline hasn't reached that position yet!
+ if (getPoint(old).x[0] > getPoint(lastPointNo).x[0]) {
+ lS->swsData[lB].leftRnd = lastPointNo;
+ }
+ }
+ // same logic as in the upper block
+ if (lS->swsData[lB].rightRnd < lastChgtPt) {
+ lS->swsData[lB].rightRnd = lastPointNo;
+ } else {
+ int old = lS->swsData[lB].rightRnd;
+ if (getPoint(old).x[0] < getPoint(lastPointNo).x[0])
+ lS->swsData[lB].rightRnd = lastPointNo;
+ }
+ }
+
+ // it's an intersection event and rS is the right edge's shape and rB is the
+ // right edge
+ if (rS) {
+ // get the edge on the right and set it in rBrd and rSrc
+ SweepTree *rE = static_cast < SweepTree * >(rS->swsData[rB].misc);
+ if (rE->elem[RIGHT]) {
+ SweepTree *rrE = static_cast < SweepTree * >(rE->elem[RIGHT]);
+ chgts[nCh].rSrc = rrE->src;
+ chgts[nCh].rBrd = rrE->bord;
+ } else {
+ chgts[nCh].rSrc = nullptr;
+ chgts[nCh].rBrd = -1;
+ }
+
+ // same code as above, except that it's on rS
+ if (rS->swsData[rB].leftRnd < lastChgtPt) {
+ rS->swsData[rB].leftRnd = lastPointNo;
+ rS->swsData[rB].nextSh = shapeHead;
+ rS->swsData[rB].nextBo = edgeHead;
+ edgeHead = rB;
+ shapeHead = rS;
+ } else {
+ int old = rS->swsData[rB].leftRnd;
+ if (getPoint(old).x[0] > getPoint(lastPointNo).x[0]) {
+ rS->swsData[rB].leftRnd = lastPointNo;
+ }
+ }
+ if (rS->swsData[rB].rightRnd < lastChgtPt) {
+ rS->swsData[rB].rightRnd = lastPointNo;
+ } else {
+ int old = rS->swsData[rB].rightRnd;
+ if (getPoint(old).x[0] < getPoint(lastPointNo).x[0])
+ rS->swsData[rB].rightRnd = lastPointNo;
+ }
+ } else { // if rS wasn't set, this is not an intersection event, so
+ // check if there is an edge to the right and set rBrd
+ SweepTree *lE = static_cast < SweepTree * >(lS->swsData[lB].misc);
+ if (lE && lE->elem[RIGHT]) {
+ SweepTree *rlE = static_cast < SweepTree * >(lE->elem[RIGHT]);
+ chgts[nCh].rSrc = rlE->src;
+ chgts[nCh].rBrd = rlE->bord;
+ } else {
+ chgts[nCh].rSrc = nullptr;
+ chgts[nCh].rBrd = -1;
+ }
+ }
+}
+
+// is this a debug function? It's calling localized "printf" ...
+void
+Shape::Validate ()
+{
+ for (int i = 0; i < numberOfPoints(); i++)
+ {
+ pData[i].rx = getPoint(i).x;
+ }
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ eData[i].rdx = getEdge(i).dx;
+ }
+ for (int i = 0; i < numberOfEdges(); i++)
+ {
+ for (int j = i + 1; j < numberOfEdges(); j++)
+ {
+ Geom::Point atx;
+ double atL, atR;
+ if (TesteIntersection (this, this, i, j, atx, atL, atR, false))
+ {
+ printf ("%i %i %f %f di=%f %f dj=%f %f\n", i, j, atx[0],atx[1],getEdge(i).dx[0],getEdge(i).dx[1],getEdge(j).dx[0],getEdge(j).dx[1]);
+ }
+ }
+ }
+ fflush (stdout);
+}
+
+void
+Shape::CheckEdges (int lastPointNo, int lastChgtPt, Shape * a, Shape * b,
+ BooleanOp mod)
+{
+
+ for (auto & chgt : chgts)
+ {
+ // if an edge addition event, we want to set curPoint to the point at which
+ // the edge was added. chgt.ptNo is automatically updated after any possible sorting and merging
+ // so thats good too :-)
+ if (chgt.type == 0)
+ {
+ Shape *lS = chgt.src;
+ int lB = chgt.bord;
+ lS->swsData[lB].curPoint = chgt.ptNo;
+ }
+ }
+ // for each event in events
+ for (auto & chgt : chgts)
+ {
+// int chLeN=chgts[cCh].ptNo;
+// int chRiN=chgts[cCh].ptNo;
+ // do the main edge (by do I mean process it, see if anything needs to be drawn, if yes, draw it)
+ if (chgt.src)
+ {
+ Shape *lS = chgt.src;
+ int lB = chgt.bord;
+ Avance (lastPointNo, lastChgtPt, lS, lB, a, b, mod);
+ }
+ // do the other edge (the right in intersection, wont exist if chgt wasn't an intersection event)
+ if (chgt.osrc)
+ {
+ Shape *rS = chgt.osrc;
+ int rB = chgt.obord;
+ Avance (lastPointNo, lastChgtPt, rS, rB, a, b, mod);
+ }
+
+ // See there are few cases due to which an edge will have a leftRnd >= lastChgtPt. Either the
+ // edge had some event associated with it (addition/removal/intersection) at that y level. Or
+ // there was some point in the previous y level that was on top of the edge, and thus an
+ // adjacency was detected and the leftRnd/rightRnd were set accordingly. If you have neither of
+ // these, leftRnd/rightRnd won't be set at all. If the case is former, that the edge had an
+ // event at the previous y level, the blocks above will automatically call Avance on the edge.
+ // However, for the latter, we have no chgt event associated with the edge. Thus, the blocks
+ // below calls Shape::Avance on edges to the left and to the right of the unique (or the left)
+ // edge. However, it's called only if leftRnd >= lastChgtPt.
+ if (chgt.lSrc)
+ {
+ Shape *nSrc = chgt.lSrc;
+ int nBrd = chgt.lBrd;
+ while (nSrc->swsData[nBrd].leftRnd >= // <-- if yes, means some event occured to this event after lastChgtPt or an adjacency was detected
+ lastChgtPt /*&& nSrc->swsData[nBrd].doneTo < lastChgtPt */ )
+ {
+ Avance (lastPointNo, lastChgtPt, nSrc, nBrd, a, b, mod);
+
+ SweepTree *node =
+ static_cast < SweepTree * >(nSrc->swsData[nBrd].misc);
+ if (node == nullptr)
+ break;
+ node = static_cast < SweepTree * >(node->elem[LEFT]);
+ if (node == nullptr)
+ break;
+ nSrc = node->src;
+ nBrd = node->bord;
+ }
+ }
+ if (chgt.rSrc)
+ {
+ Shape *nSrc = chgt.rSrc;
+ int nBrd = chgt.rBrd;
+ while (nSrc->swsData[nBrd].rightRnd >=
+ lastChgtPt /*&& nSrc->swsData[nBrd].doneTo < lastChgtPt */ )
+ {
+ Avance (lastPointNo, lastChgtPt, nSrc, nBrd, a, b, mod);
+
+ SweepTree *node =
+ static_cast < SweepTree * >(nSrc->swsData[nBrd].misc);
+ if (node == nullptr)
+ break;
+ node = static_cast < SweepTree * >(node->elem[RIGHT]);
+ if (node == nullptr)
+ break;
+ nSrc = node->src;
+ nBrd = node->bord;
+ }
+ }
+ }
+}
+
+void
+Shape::Avance (int lastPointNo, int lastChgtPt, Shape * lS, int lB, Shape * /*a*/,
+ Shape * b, BooleanOp mod)
+{
+ double dd = HalfRound (1); // get the smallest step you can take in the rounding grid.
+ bool avoidDiag = false; // triggers some special diagonal avoiding code below
+// if ( lastChgtPt > 0 && pts[lastChgtPt-1].y+dd == pts[lastChgtPt].y ) avoidDiag=true;
+
+ // my best guess is that direct acts kinda as an inverter. If set to true, edges are drawn
+ // in the direction they should be drawn in, if set to false, they are inverted. This is needed
+ // if the edge is coming from shape b and the mod is bool_op_diff or bool_op_symdiff. This is how
+ // Livarot does these boolean operations.
+ bool direct = true;
+ if (lS == b && (mod == bool_op_diff || mod == bool_op_symdiff))
+ direct = false;
+ // get the leftRnd and rightRnd points of the edge lB. For most edges, leftRnd and rightRnd are identical
+ // however when you have a horizontal edge, they can be different.
+ int lftN = lS->swsData[lB].leftRnd;
+ int rgtN = lS->swsData[lB].rightRnd;
+ // doneTo acts as a marker. Once Avance processes an edge at a certain y level, it sets doneTo to the
+ // right most point at that y level. See the end of this function to see how it does this.
+ if (lS->swsData[lB].doneTo < lastChgtPt)
+ {
+ // the last point till which this edge has been drawn
+ int lp = lS->swsData[lB].curPoint;
+ // if the last point exists and lastChgtPt.y is just dd (1 rounded step) bigger than lastpoint.y
+ // in simpler words, the last point drawn is just 1 rounded step above lastChgtPt
+ // Look, if there is a potential edge to draw, that edge is going to have its upper endpoint at lp
+ // and could have the lower endpoint lftN...rgtN whatever, but we are sure that it can't go any lower (downwards)
+ // than lastChgtPt. If this "if" block evalues to true, there is a possibility we might an edge that would
+ // be diagonal for example 1 rounded unit dd down and to the right. We would like to avoid this if there is
+ // a point right below, so we can draw two edges, first down and then right. See the figure in the header
+ // docs to see what I mean
+ if (lp >= 0 && getPoint(lp).x[1] + dd == getPoint(lastChgtPt).x[1])
+ avoidDiag = true;
+ // if the edge is horizontal
+ if (lS->eData[lB].rdx[1] == 0)
+ {
+ // tjs de gauche a droite et pas de diagonale -- > left to right horizonal edge won't be diagonal (since it's horizontal :P)
+ if (lS->eData[lB].rdx[0] >= 0) // edge is left to right
+ {
+ for (int p = lftN; p <= rgtN; p++)
+ {
+ DoEdgeTo (lS, lB, p, direct, true);
+ lp = p;
+ }
+ }
+ else // edge is right to left
+ {
+ for (int p = lftN; p <= rgtN; p++)
+ {
+ DoEdgeTo (lS, lB, p, direct, false);
+ lp = p;
+ }
+ }
+ }
+ else if (lS->eData[lB].rdx[1] > 0) // the edge is top to bottom
+ {
+ if (lS->eData[lB].rdx[0] >= 0) // edge is top to bottom and left to right
+ {
+
+ for (int p = lftN; p <= rgtN; p++) // for the range lftN..rgtN
+ {
+ // if avoidDiag is true, point p is lftN and the point the edge is to be drawn to (lftN) has an x that's
+ // 1 rounded unit (dd) greater than the last point drawn. So basically lftN is one unit down and one unit
+ // to the right of lp
+ if (avoidDiag && p == lftN && getPoint(lftN).x[0] == getPoint(lp).x[0] + dd)
+ {
+ // we would want to avoid the diagonal but only if there is a point (in our directed graph)
+ // just to the left of the original lower endpoint and instead of doing a diagonal, we can create an edge to that point
+ // and then from that point to the original endpoint. see the figure in the header docs to see what I mean
+ if (lftN > 0 && lftN - 1 >= lastChgtPt // if there is a point in the figure just below lp and to the left of lftN
+ && getPoint(lftN - 1).x[0] == getPoint(lp).x[0]) // that point has x equal to that of lp (right below it)
+ {
+ DoEdgeTo (lS, lB, lftN - 1, direct, true); // draw an edge to lftn - 1
+ DoEdgeTo (lS, lB, lftN, direct, true); // then draw an edge to lftN
+ }
+ else
+ {
+ DoEdgeTo (lS, lB, lftN, direct, true);
+ }
+ }
+ else
+ {
+ DoEdgeTo (lS, lB, p, direct, true);
+ }
+ lp = p;
+ }
+ }
+ else
+ {
+
+ for (int p = rgtN; p >= lftN; p--) // top to bottom and right to left
+ {
+ // exactly identical to the code above except that it's a diagonal down and to the left
+ if (avoidDiag && p == rgtN && getPoint(rgtN).x[0] == getPoint(lp).x[0] - dd)
+ {
+ if (rgtN < numberOfPoints() && rgtN + 1 < lastPointNo // refer to first diagram in header docs to see why this condition
+ && getPoint(rgtN + 1).x[0] == getPoint(lp).x[0])
+ {
+ DoEdgeTo (lS, lB, rgtN + 1, direct, true);
+ DoEdgeTo (lS, lB, rgtN, direct, true);
+ }
+ else
+ {
+ DoEdgeTo (lS, lB, rgtN, direct, true);
+ }
+ }
+ else
+ {
+ DoEdgeTo (lS, lB, p, direct, true);
+ }
+ lp = p;
+ }
+ }
+ }
+ else // edge is bottom to top
+ {
+ if (lS->eData[lB].rdx[0] >= 0) // edge is bottom to top and left to right
+ {
+
+ for (int p = rgtN; p >= lftN; p--)
+ {
+ if (avoidDiag && p == rgtN && getPoint(rgtN).x[0] == getPoint(lp).x[0] - dd)
+ {
+ if (rgtN < numberOfPoints() && rgtN + 1 < lastPointNo
+ && getPoint(rgtN + 1).x[0] == getPoint(lp).x[0])
+ {
+ DoEdgeTo (lS, lB, rgtN + 1, direct, false); // draw an edge that goes down
+ DoEdgeTo (lS, lB, rgtN, direct, false); // draw an edge that goes left
+ }
+ else
+ {
+ DoEdgeTo (lS, lB, rgtN, direct, false);
+ }
+ }
+ else
+ {
+ DoEdgeTo (lS, lB, p, direct, false);
+ }
+ lp = p;
+ }
+ }
+ else
+ {
+ // bottom to top and right to left edge
+ for (int p = lftN; p <= rgtN; p++)
+ {
+ // totally identical as the first block that I explain with a figure in the header docs
+ if (avoidDiag && p == lftN && getPoint(lftN).x[0] == getPoint(lp).x[0] + dd)
+ {
+ if (lftN > 0 && lftN - 1 >= lastChgtPt
+ && getPoint(lftN - 1).x[0] == getPoint(lp).x[0])
+ {
+ DoEdgeTo (lS, lB, lftN - 1, direct, false);
+ DoEdgeTo (lS, lB, lftN, direct, false);
+ }
+ else
+ {
+ DoEdgeTo (lS, lB, lftN, direct, false);
+ }
+ }
+ else
+ {
+ DoEdgeTo (lS, lB, p, direct, false);
+ }
+ lp = p;
+ }
+ }
+ }
+ lS->swsData[lB].curPoint = lp;
+ }
+ // see how doneTo is being set to lastPointNo - 1? See the figure in the header docs of this function and you'll see
+ // what lastPointNo is, subtract one and you get the right most point that's just above lastPointNo. This marks that
+ // this edge has been processed til that y level.
+ lS->swsData[lB].doneTo = lastPointNo - 1;
+}
+
+void
+Shape::DoEdgeTo (Shape * iS, int iB, int iTo, bool direct, bool sens)
+{
+ int lp = iS->swsData[iB].curPoint;
+ int ne = -1;
+ if (sens)
+ {
+ if (direct)
+ ne = AddEdge (lp, iTo);
+ else
+ ne = AddEdge (iTo, lp);
+ }
+ else
+ {
+ if (direct)
+ ne = AddEdge (iTo, lp);
+ else
+ ne = AddEdge (lp, iTo);
+ }
+ if (ne >= 0 && _has_back_data)
+ {
+ ebData[ne].pathID = iS->ebData[iB].pathID;
+ ebData[ne].pieceID = iS->ebData[iB].pieceID;
+ if (iS->eData[iB].length < 0.00001)
+ {
+ ebData[ne].tSt = ebData[ne].tEn = iS->ebData[iB].tSt;
+ }
+ else
+ {
+ double bdl = iS->eData[iB].ilength;
+ Geom::Point bpx = iS->pData[iS->getEdge(iB).st].rx;
+ Geom::Point bdx = iS->eData[iB].rdx;
+ Geom::Point psx = getPoint(getEdge(ne).st).x;
+ Geom::Point pex = getPoint(getEdge(ne).en).x;
+ Geom::Point psbx=psx-bpx;
+ Geom::Point pebx=pex-bpx;
+ double pst = dot(psbx,bdx) * bdl;
+ double pet = dot(pebx,bdx) * bdl;
+ pst = iS->ebData[iB].tSt * (1 - pst) + iS->ebData[iB].tEn * pst;
+ pet = iS->ebData[iB].tSt * (1 - pet) + iS->ebData[iB].tEn * pet;
+ ebData[ne].tEn = pet;
+ ebData[ne].tSt = pst;
+ }
+ }
+ iS->swsData[iB].curPoint = iTo;
+ if (ne >= 0)
+ {
+ int cp = iS->swsData[iB].firstLinkedPoint;
+ swsData[ne].firstLinkedPoint = iS->swsData[iB].firstLinkedPoint;
+ while (cp >= 0)
+ {
+ pData[cp].askForWindingB = ne;
+ cp = pData[cp].nextLinkedPoint;
+ }
+ iS->swsData[iB].firstLinkedPoint = -1;
+ }
+}
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