internal static TinyQueue divideSegment(SweepEvent se, Point p, TinyQueue queue)
{
var r = new SweepEvent(p, false, se, se.isSubject);
var l = new SweepEvent(p, true, se.otherEvent, se.isSubject);
if (equals(se.point, se.otherEvent.point))
{
MessageBox.Show("what is that?" + se.ToString());
}
r.contourId = l.contourId = se.contourId;
// avoid a rounding error. The left _event would be processed after the right _event
if (compareEvents(l, se.otherEvent) > 0)
{
se.otherEvent.left = true;
l.left = false;
}
// avoid a rounding error. The left _event would be processed after the right _event
// if (compareEvents(se, r) > 0) {}
se.otherEvent.otherEvent = l;
se.otherEvent = r;
queue.push(l);
queue.push(r);
return(queue);
}
internal static TinyQueue fillQueue(Point[][][] subject, Point[][][] clipping, double[] sbbox, double[] cbbox)
{
TinyQueue eventQueue = new TinyQueue(null, compareEvents);
Point[][] polygonSet;
bool isExteriorRing;
int len = subject.GetLength(0);
for (int i = 0; i < len; i++)
{
polygonSet = subject[i];
int jj = polygonSet.GetLength(0);
for (int j = 0; j < jj; j++)
{
isExteriorRing = (j == 0);
if (isExteriorRing)
{
contourId++;
}
processPolygon(polygonSet[j], true, contourId, eventQueue, sbbox, isExteriorRing);
}
}
for (int i = 0, ii = clipping.GetLength(0); i < ii; i++)
{
polygonSet = clipping[i];
int jj = polygonSet.GetLength(0);
for (int j = 0; j < jj; j++)
{
isExteriorRing = (j == 0);
if (isExteriorRing)
{
contourId++;
}
processPolygon(polygonSet[j], false, contourId, eventQueue, cbbox, isExteriorRing);
}
}
return(eventQueue);
}
internal static void processPolygon(Point[] contourOrHole, bool isSubject, int depth, TinyQueue queue, double[] bbox, bool isExteriorRing)
{
int len = contourOrHole.GetLength(0) - 1;
for (int i = 0; i < len; i++)
{
processSegment(contourOrHole[i], contourOrHole[i + 1], isSubject, depth + 1, queue, bbox, isExteriorRing);
}
}
///* eslint-disable no-unused-vars, no-debugger, no-undef */
//function iteratorEquals(it1, it2) {
// return it1._cursor === it2._cursor;
//}
//function _renderSweepLine(sweepLine, pos, _event)
//{
//var map = window.map;
//if (!map) return;
//if (window.sws) window.sws.forEach(function (p) {
//map.removeLayer(p);
//});
//window.sws = [];
//sweepLine.forEach(function (e) {
//var poly = L.polyline([
// e.point.slice().reverse(),
// e.otherEvent.point.slice().reverse()
//], {color: 'green'}).addTo(map);
//window.sws.push(poly);
//});
//if (window.vt) map.removeLayer(window.vt);
//var v = pos.slice();
//var b = map.getBounds();
//window.vt = L.polyline([
//[b.getNorth(), v[0]],
//[b.getSouth(), v[0]]
//], {color: 'green', weight: 1}).addTo(map);
//if (window.ps) map.removeLayer(window.ps);
//window.ps = L.polyline([
//_event.point.slice().reverse(),
//_event.otherEvent.point.slice().reverse()
//], {color: 'black', weight: 9, opacity: 0.4}).addTo(map);
//debugger;
//}
///* eslint-enable no-unused-vars, no-debugger, no-undef */
internal static List <SweepEvent> subdivideSegments(TinyQueue eventQueue, Point[][][] subject, Point[][][] clipping, double[] sbbox, double[] cbbox, Operation operation)
{
RedBlackTree sweepLine = new RedBlackTree(_comp_Segm);
List <SweepEvent> sortedEvents = new List <SweepEvent>();
double rightbound = Math.Min(sbbox[2], cbbox[2]);
RedBlackTreeIterator prev, next;
SweepEvent prevEvent, prevprevEvent;
while (eventQueue.length > 0)
{
SweepEvent _event = eventQueue.pop();
sortedEvents.Add(_event);
// optimization by bboxes for intersection and difference goes here - коммент оригинала
if ((operation == Operation.INTERSECTION && _event.point.X > rightbound) || (operation == Operation.DIFFERENCE && _event.point.X > sbbox[2]))
{
break;
}
if (_event.left)
{
sweepLine = sweepLine.insert(_event, _event);
//_renderSweepLine(sweepLine, _event.point, _event); - коммент оригинала
next = sweepLine.find(_event);
prev = sweepLine.find(_event);
_event.iterator = sweepLine.find(_event);
if (!prev.node.Equals(sweepLine.begin.node)) // ??? (prev.node !== sweepLine.begin)
{
prev.prev();
}
else
{
prev = sweepLine.begin;
prev.prev();
prev.next();
}
next.next();
//--- prevEvent = (prev.key || null), prevprevEvent;
prevEvent = (SweepEvent)Convert.ChangeType(prev.key, typeof(SweepEvent));
computeFields(_event, prevEvent, operation);
if (next.node != null)
{
if (possibleIntersection(_event, (SweepEvent)Convert.ChangeType(next.key, typeof(SweepEvent)), eventQueue) == 2)
{
computeFields(_event, prevEvent, operation);
computeFields(_event, (SweepEvent)Convert.ChangeType(next.key, typeof(SweepEvent)), operation);
}
}
if (prev.node != null)
{
if (possibleIntersection((SweepEvent)Convert.ChangeType(prev.key, typeof(SweepEvent)), _event, eventQueue) == 2)
{
RedBlackTreeIterator prevprev = sweepLine.find((SweepEvent)Convert.ChangeType(prev.key, typeof(SweepEvent)));
if (!prevprev.node.Equals(sweepLine.begin.node)) //prevprev.node != sweepLine.begin
{
prevprev.prev();
}
else
{
prevprev = sweepLine.find((SweepEvent)Convert.ChangeType(sweepLine.end.key, typeof(SweepEvent)));
prevprev.next();
}
prevprevEvent = (SweepEvent)Convert.ChangeType(prevprev.key, typeof(SweepEvent));
computeFields(prevEvent, prevprevEvent, operation);
computeFields(_event, prevEvent, operation);
}
}
}
else
{
_event = _event.otherEvent;
next = sweepLine.find(_event);
prev = sweepLine.find(_event);
// _renderSweepLine(sweepLine, _event.otherEvent.point, _event); - коммент оригинала
if (!(prev != null && next != null))
{
continue;
}
if (!prev.node.Equals(sweepLine.begin.node)) // prev.node != sweepLine.begin
{
prev.prev();
}
else
{
prev = sweepLine.begin;
prev.prev();
prev.next();
}
next.next();
sweepLine = sweepLine.remove(_event);
// _renderSweepLine(sweepLine, _event.otherEvent.point, _event); - коммент оригинала
if (next.node != null && prev.node != null)
{
if (prev.node.value != null && next.node.value != null) //-- if (typeof prev.node.value != 'undefined' && typeof next.node.value != 'undefined')
{
possibleIntersection((SweepEvent)Convert.ChangeType(prev.key, typeof(SweepEvent)), (SweepEvent)Convert.ChangeType(next.key, typeof(SweepEvent)), eventQueue);
}
}
}
}
return(sortedEvents);
}
//var max = Math.max;
//var min = Math.min;
/**
* @param {Array<Number>} s1
* @param {Array<Number>} s2
* @param {Boolean} isSubject
* @param {Queue} eventQueue
* @param {Array<Number>} bbox
*/
internal static void processSegment(Point s1, Point s2, bool isSubject, int depth, TinyQueue eventQueue, double[] bbox, bool isExteriorRing)
{
// Possible degenerate condition.
// if (equals(s1, s2)) return;
var e1 = new SweepEvent(s1, false, null, isSubject);
var e2 = new SweepEvent(s2, false, e1, isSubject);
e1.otherEvent = e2;
e1.contourId = e2.contourId = depth;
if (!isExteriorRing)
{
e1.isExteriorRing = false;
e2.isExteriorRing = false;
}
if (compareEvents(e1, e2) > 0)
{
e2.left = true;
}
else
{
e1.left = true;
}
bbox[0] = Math.Min(bbox[0], s1.X);
bbox[1] = Math.Min(bbox[1], s1.Y);
bbox[2] = Math.Max(bbox[2], s1.X);
bbox[3] = Math.Max(bbox[3], s1.Y);
// Pushing it so the queue is sorted from left to right, with object on the left having the highest priority.
eventQueue.push(e1);
eventQueue.push(e2);
}
internal static int possibleIntersection(SweepEvent se1, SweepEvent se2, TinyQueue queue)
{
// that disallows self-intersecting polygons,
// did cost us half a day, so I'll leave it
// out of respect
// if (se1.isSubject === se2.isSubject) return;
var inter = SegmentIntersection(se1.point, se1.otherEvent.point, se2.point, se2.otherEvent.point);
var nintersections = inter != null ? inter.Length : 0;
if (nintersections == 0)
{
return(0); // no intersection
}
// the line segments intersect at an endpoint of both line segments
if ((nintersections == 1) && (equals(se1.point, se2.point) || equals(se1.otherEvent.point, se2.otherEvent.point)))
{
return(0);
}
if (nintersections == 2 && se1.isSubject == se2.isSubject)
{
// if(se1.contourId === se2.contourId){
// console.warn('Edges of the same polygon overlap',
// se1.point, se1.otherEvent.point, se2.point, se2.otherEvent.point);
// }
//throw new Error('Edges of the same polygon overlap');
return(0);
}
// The line segments associated to se1 and se2 intersect
if (nintersections == 1)
{
// if the intersection point is not an endpoint of se1
if (!equals(se1.point, inter[0]) && !equals(se1.otherEvent.point, inter[0]))
{
divideSegment(se1, inter[0], queue);
}
// if the intersection point is not an endpoint of se2
if (!equals(se2.point, inter[0]) && !equals(se2.otherEvent.point, inter[0]))
{
divideSegment(se2, inter[0], queue);
}
return(1);
}
// The line segments associated to se1 and se2 overlap
var events = new List <SweepEvent>();
var leftCoincide = false;
var rightCoincide = false;
if (equals(se1.point, se2.point))
{
leftCoincide = true; // linked
}
else if (compareEvents(se1, se2) == 1)
{
events.Add(se2);
events.Add(se1);
}
else
{
events.Add(se1);
events.Add(se2);
}
if (equals(se1.otherEvent.point, se2.otherEvent.point))
{
rightCoincide = true;
}
else if (compareEvents(se1.otherEvent, se2.otherEvent) == 1)
{
events.Add(se2.otherEvent);
events.Add(se1.otherEvent);
}
else
{
events.Add(se1.otherEvent);
events.Add(se2.otherEvent);
}
if ((leftCoincide && rightCoincide) || leftCoincide) // both line segments are equal or share the left endpoint
{
se1.type = EdgeType.NON_CONTRIBUTING;
se2.type = (se1.inOut == se2.inOut) ? EdgeType.SAME_TRANSITION : EdgeType.DIFFERENT_TRANSITION;
if (leftCoincide && !rightCoincide)
{
// honestly no idea, but changing events selection from [2, 1] to [0, 1] fixes the overlapping self-intersecting polygons issue
divideSegment(events[1].otherEvent, events[0].point, queue);
}
return(2);
}
if (rightCoincide) // the line segments share the right endpoint
{
divideSegment(events[0], events[1].point, queue);
return(3);
}
if (events[0] != events[3].otherEvent) // no line segment includes totally the other one
{
divideSegment(events[0], events[1].point, queue);
divideSegment(events[1], events[2].point, queue);
return(3);
}
// one line segment includes the other one
divideSegment(events[0], events[1].point, queue);
divideSegment(events[3].otherEvent, events[2].point, queue);
return(3);
}
