private OwnVector2 findNearestOppositeEdge(CircularLinkedList<Vertex> LAV, Vertex current, out Vertex firstEdgePoint, out Vertex secondEdgePoint)
{
firstEdgePoint = null;
secondEdgePoint = null;
Node<Vertex> temp = LAV.Find(current).Next;
Point2D intersectionPoint = new Point2D(0,0);
Point2D currentClosest = new Point2D(0, 0);
Vertices testPoly = new Vertices();
foreach(Vertex v in LAV)
{
testPoly.Add(v.getPoint());
}
while (!temp.Next.Value.Equals(current))
{
//check if the edge is not behind the vertex
if(LineTools.LineIntersect(
current.getRayStart(),
new Point2D(current.getRayStart().X + (-current.getRayDirection().X * int.MaxValue), -current.getRayStart().Y + (-current.getRayDirection().Y * int.MaxValue)),
temp.Value.getPoint(),
temp.Next.Value.getPoint(),
true,false, out intersectionPoint))
{
//Calc Bi (intersection ray current + bisector of triangle)
Point2D intersect1 = new Point2D(LineTools.LineIntersect(
current.prevEdge.getFirstPoint(),
current.prevEdge.getSecondPoint(),
temp.Value.getPoint(),
temp.Next.Value.getPoint()));
Point2D intersect2 = new Point2D(LineTools.LineIntersect(
current.nextEdge.getFirstPoint(),
current.nextEdge.getSecondPoint(),
temp.Value.getPoint(),
temp.Next.Value.getPoint()));
Vertices tempVer = new Vertices();
tempVer.Add(current.getPoint());
tempVer.Add(intersect1);
tempVer.Add(intersect2);
Vertex edgeBisector1 = new Vertex(intersect1, -1);
edgeBisector1.prevEdge = new Edge(current.getPoint(), intersect1);
edgeBisector1.nextEdge = new Edge(intersect1, intersect2);
edgeBisector1.update();
Point2D Bi = new Point2D(LineTools.LineIntersect(
current.getRayStart(),
current.getRayStepPoint(),
edgeBisector1.getRayStart(),
edgeBisector1.getRayStepPoint()));
if (tempVer.PointInPolygon(ref Bi) == -1)
{
edgeBisector1 = new Vertex(intersect2, -1);
edgeBisector1.prevEdge = new Edge(current.getPoint(), intersect2);
edgeBisector1.nextEdge = new Edge(intersect2, intersect1);
edgeBisector1.update();
Bi = new Point2D(LineTools.LineIntersect(
current.getRayStart(),
current.getRayStepPoint(),
edgeBisector1.getRayStart(),
edgeBisector1.getRayStepPoint()));
if (tempVer.PointInPolygon(ref Bi) == -1)
{
temp = temp.Next;
continue;
}
}
//check if Bi inside polygon to begin with
if (testPoly.PointInPolygon(ref Bi) == -1)
{
temp = temp.Next;
continue;
}
//check if Bi is in area defined by opposing edge and it's bisectors
//first check if both bisectors of edge are convex so we can see if Bi is inside the defined triangle
if(temp.Value.isConvex() && temp.Next.Value.isConvex())
{
OwnVector2 trianglePoint = LineTools.LineIntersect(
temp.Value.getRayStart(),
temp.Value.getRayStepPoint(),
temp.Next.Value.getRayStart(),
temp.Next.Value.getRayStepPoint());
if (!MathHelper.PointInTriangle(trianglePoint, temp.Value.getPoint(), temp.Next.Value.getPoint(), Bi))
{
temp = temp.Next;
continue;
}
}
else{
Vertices test = new Vertices();
int sign1 = temp.Value.isConvex() ? 1 : -1;
int sign2 = temp.Next.Value.isConvex() ? 1 : -1;
test.Add(temp.Value.getPoint());
test.Add(temp.Next.Value.getPoint());
test.Add(new Point2D(
temp.Next.Value.getPoint().X + (sign2 * temp.Next.Value.getRayDirection().X * int.MaxValue),
temp.Next.Value.getPoint().Y + (sign2 * temp.Next.Value.getRayDirection().Y * int.MaxValue)));
test.Add(new Point2D(
temp.Value.getPoint().X + (sign1 * temp.Value.getRayDirection().X * int.MaxValue),
temp.Value.getPoint().Y + (sign1 * temp.Value.getRayDirection().Y * int.MaxValue)));
if (test.PointInPolygon(ref Bi) == -1)
{
temp = temp.Next;
continue;
}
}
if (currentClosest.Equals(Point2D.Zero) || Point2D.Distance(current.getPoint(), currentClosest) > Point2D.Distance(current.getPoint(), Bi))
{
currentClosest = Bi;
firstEdgePoint = temp.Value;
secondEdgePoint = temp.Next.Value;
}
}
temp = temp.Next;
}
testDots.Add(currentClosest);
return currentClosest;
}
private void findClosestIntersectionAndStore(CircularLinkedList<Vertex> LAV, Vertex prev, Vertex current, Vertex next)
{
Vertices testPoly = new Vertices();
foreach (Vertex v in LAV)
{
testPoly.Add(v.getPoint());
}
OwnVector2 prevIntersection = LineTools.LineIntersect(
prev.getRayStart(), prev.getRayStepPoint(),
current.getRayStart(), current.getRayStepPoint());
OwnVector2 nextIntersection = LineTools.LineIntersect(
current.getRayStart(), current.getRayStepPoint(),
next.getRayStart(), next.getRayStepPoint());
OwnVector2 nearestOppositeIntersection = OwnVector2.Zero;
Point2D testPrev = new Point2D(prevIntersection);
if (testPoly.PointInPolygon(ref testPrev) == -1)
{
prevIntersection = Point2D.Zero;
}
Point2D testNext = new Point2D(nextIntersection);
if (testPoly.PointInPolygon(ref testNext) == -1)
{
nextIntersection = Point2D.Zero;
}
Vertex firstEdgePoint = null;
Vertex secondEdgePoint = null;
if(current.isConcave())
{
nearestOppositeIntersection = findNearestOppositeEdge(LAV, current, out firstEdgePoint, out secondEdgePoint);
}
float distPrev = prevIntersection.Equals(Point2D.Zero) ? float.MaxValue : OwnVector2.Distance(current.getPoint(), prevIntersection);
float distNext = nextIntersection.Equals(Point2D.Zero) ? float.MaxValue : OwnVector2.Distance(current.getPoint(), nextIntersection);
float distOpposite = float.MaxValue;
if (distPrev == 0)
{
prevIntersection = Point2D.Zero;
}
if (distNext == 0)
{
nextIntersection = Point2D.Zero;
}
if (current.isConcave())
{
distOpposite = OwnVector2.Distance(current.getPoint(), nearestOppositeIntersection);
}
if (prevIntersection.Equals(OwnVector2.Zero) && nextIntersection.Equals(OwnVector2.Zero) && nearestOppositeIntersection.Equals(OwnVector2.Zero))
{
return;
}
if ((nextIntersection.Equals(OwnVector2.Zero) && nearestOppositeIntersection.Equals(OwnVector2.Zero)) || distPrev < distNext && distPrev < distOpposite)
{
Event e = new Event(new Point2D(prevIntersection), SLAV.IndexOf(LAV), EventType.Edge);
e.storeFirstPoint(prev);
e.storeSecondPoint(current);
Q.Enqueue(e, distPrev);
}
else if ((nearestOppositeIntersection.Equals(OwnVector2.Zero) && prevIntersection.Equals(OwnVector2.Zero)) || distNext <= distPrev && distNext <= distOpposite)
{
Event e = new Event(new Point2D(nextIntersection), SLAV.IndexOf(LAV), EventType.Edge);
e.storeFirstPoint(current);
e.storeSecondPoint(next);
Q.Enqueue(e, distNext);
}
else
{
Event e = new Event(new Point2D(nearestOppositeIntersection), SLAV.IndexOf(LAV), EventType.Split);
e.storeFirstPoint(current);
e.storeFirstEdgePoint(firstEdgePoint);
e.storeSecondEdgePoint(secondEdgePoint);
Q.Enqueue(e, distOpposite);
}
}
