private List <Edge> IntersectedEdges(Vector2 edgeStart, SliceHierarchy father, Vector2 edgeEnd)
{
var interEdges = new List <Edge>();
for (var p = father.Points.First; p != null; p = p.Next)
{
if (p.Value.v2.Equals(edgeStart))
{
continue;
}
var areIntersect = WholeSlicePlane.LineSegmentsIntersection(
edgeStart,
edgeEnd,
p.Value.v2,
LinkedListExtensions.Next(p).Value.v2, out var interPoint);
//intersection point with father(outer) points
if (areIntersect)
{
var point = p.Value.v2.x > LinkedListExtensions.Next(p).Value.v2.x ? p : LinkedListExtensions.Next(p);
var edge = new Edge {
FDiscret = p, SDiscret = LinkedListExtensions.Next(p), MaxXdiscret = point, Inter = interPoint
};
interEdges.Add(edge);
}
}
return(interEdges);
}
private void UnionFatherAndChildPoints(SliceHierarchy child, SliceHierarchy father,
LinkedListNode <MappedPoint> childStartPoint, LinkedListNode <MappedPoint> fatherStartPoint)
{
var prev = fatherStartPoint;
for (var p3 = childStartPoint; p3 != LinkedListExtensions.Previous(childStartPoint); p3 = LinkedListExtensions.Next(p3))
{
prev = father.Points.AddAfter(prev, p3.Value);
}
prev = father.Points
.AddAfter(prev, LinkedListExtensions.Previous(childStartPoint).Value);
prev = father.Points.AddAfter(prev, childStartPoint.Value);
father.Points.AddAfter(prev, fatherStartPoint.Value);
father.MaxX = Mathf.Max(father.MaxX, child.MaxX);
}
private void ReverseIfShould(SliceHierarchy sliceHierarchy)
{
if (sliceHierarchy.Level % 2 == 0)
{
if (!ArePointsCounterClockwise(sliceHierarchy.Points))
{
sliceHierarchy.Points = LinkedListExtensions.ReversedLinkedList(sliceHierarchy.Points);
}
}
else
{
if (ArePointsCounterClockwise(sliceHierarchy.Points))
{
sliceHierarchy.Points = LinkedListExtensions.ReversedLinkedList(sliceHierarchy.Points);
}
}
}
private bool ArePolygonsIntersect(SliceHierarchy pol1, SliceHierarchy pol2)
{
for (var p1 = pol1.Points.First; p1 != null; p1 = p1.Next)
{
for (var p2 = pol2.Points.First; p2 != null; p2 = p2.Next)
{
var areIntersect = LineSegmentsIntersection(p1.Value.v2, LinkedListExtensions.Next(p1).Value.v2, p2.Value.v2,
LinkedListExtensions.Next(p2).Value.v2, out var interPoint);
if (areIntersect)
{
return(true);
}
}
}
return(false);
}
private int IntersectionCount(SliceHierarchy outerPoints, MappedPoint point)
{
var intersectionCount = 0;
for (var p = outerPoints.Points.First; p != null; p = p.Next)
{
var end = new Vector2(1000000f, 0);
var areIntersect = LineSegmentsIntersection(point.v2,
end,
p.Value.v2,
LinkedListExtensions.Next(p).Value.v2, out var intersection);
if (areIntersect)
{
intersectionCount++;
}
}
return(intersectionCount);
}
private bool IsPolygonInsidePolygon(SliceHierarchy intendedСhild, SliceHierarchy intendedFather)
{
var intersectionCountPrev = IntersectionCount(intendedFather, intendedСhild.Points.First.Value);
return(intersectionCountPrev % 2 == 1);
}
public Triangulator(SliceHierarchy sliceHierarchy)
{
//even should be counterclockwise
ReverseIfShould(sliceHierarchy);
sliceHierarchy.Childs.RemoveAll(item => item == null);
sliceHierarchy.Childs = new List <SliceHierarchy>(sliceHierarchy.Childs.OrderByDescending(x => x.MaxX));
for (var j = 0; j < sliceHierarchy.Childs.Count; j++)
{
var child = sliceHierarchy.Childs[j];
if (child == null)
{
continue;
}
//odd should be clockwise
ReverseIfShould(child);
// child point with max x
var childMaxX = child.MaxX;
LinkedListNode <MappedPoint> childMaxXObj = null;
for (var p = child.Points.First; p != null; p = p.Next)
{
if (p.Value.v2.x == childMaxX)
{
childMaxXObj = p;
}
}
//intersected edges
var interEdges = IntersectedEdges(childMaxXObj.Value.v2, child.Father, new Vector2(1000000f, 0));
if (!interEdges.Any())
{
continue;
}
// nearest edge
var nearestEdgeDist = interEdges.Min(x => Mathf.Abs(x.MaxXdiscret.Value.v2.x - childMaxXObj.Value.v2.x));
Edge nearestEdge = null;
foreach (var e in interEdges)
{
if (Mathf.Abs(e.MaxXdiscret.Value.v2.x - childMaxXObj.Value.v2.x) == nearestEdgeDist)
{
nearestEdge = e;
break;
}
}
// childMaxX..............................nearestEdge.Inter
// .................MinAnglePoint.........
// .................................P2....
// .......................................nearestEdge.discret
var pointsInTriangle = PointsInTriangle(
child.Father.Points,
childMaxXObj.Value.v2,
nearestEdge.MaxXdiscret.Value.v2,
nearestEdge.Inter);
// if points were caught than should pick with smallest angle
if (pointsInTriangle.Any())
{
var minAngleObj = pointsInTriangle
.OrderBy(x =>
Vector2.Angle(nearestEdge.Inter - childMaxXObj.Value.v2, x.Value.v2 - childMaxXObj.Value.v2))
.ThenBy(x => Mathf.Abs(x.Value.v2.x - childMaxXObj.Value.v2.x)).First();
nearestEdge.MaxXdiscret = minAngleObj;
}
//intersected edges
var selfInterEdges = IntersectedEdges(childMaxXObj.Value.v2, child, nearestEdge.MaxXdiscret.Value.v2);
if (selfInterEdges.Any())
{
childMaxXObj = selfInterEdges
.OrderBy(x => Vector2.Distance(x.MaxXdiscret.Value.v2, nearestEdge.MaxXdiscret.Value.v2))
.First()
.MaxXdiscret;
}
// union father and child
UnionFatherAndChildPoints(
child,
child.Father,
childMaxXObj,
nearestEdge.MaxXdiscret);
sliceHierarchy.Childs[j] = null;
}
_pointsN = sliceHierarchy.Points;
}
