public int Compare_X(EventPoint E1, EventPoint E2)
{
double m1 = (E1.edge.Y - E1.point.Y) / (E1.edge.X - E1.point.X);
double b1 = E1.point.Y - (m1 * E1.point.X);
double m2 = (E2.edge.Y - E2.point.Y) / (E2.edge.X - E2.point.X);
double b2 = E2.point.Y - (m2 * E2.point.X);
double x1 = (Y - b1) / m1;
double x2 = (Y - b2) / m2;
if (x1 > x2)
{
return(1);
}
else if (x1 < x2)
{
return(-1);
}
return(0);
}
public int Compare_Y(EventPoint E1, EventPoint E2)
{
if (E2.point.Y < E1.point.Y)
{
return(-1);
}
if (E2.point.Y > E1.point.Y)
{
return(1);
}
if (E2.point.X < E1.point.X)
{
return(1);
}
if (E2.point.X > E1.point.X)
{
return(-1);
}
return(0);
}
public override void Run(List <CGUtilities.Point> points, List <CGUtilities.Line> lines, List <CGUtilities.Polygon> polygons, ref List <CGUtilities.Point> outPoints, ref List <CGUtilities.Line> outLines, ref List <CGUtilities.Polygon> outPolygons)
{
OrderedSet <EventPoint> Q = new OrderedSet <EventPoint>(Compare_Y);
Dictionary <int, EventPoint> prev_event = new Dictionary <int, EventPoint>();
Dictionary <int, EventPoint> helper = new Dictionary <int, EventPoint>();
OrderedSet <EventPoint> T = new OrderedSet <EventPoint>(Compare_X);
string type;
for (int i = 0; i < polygons[0].lines.Count; ++i)
{
Point n1 = polygons[0].lines[(polygons[0].lines.Count + i - 1) % polygons[0].lines.Count].Start;
Point p = polygons[0].lines[i].Start;
Point n2 = polygons[0].lines[(i + 1) % polygons[0].lines.Count].Start;
double angle = CalcAngle(n1, p, n2);
if (((n1.Y < p.Y) || ((n1.Y == p.Y) && (n1.X > p.Y))) && ((n2.Y < p.Y) || ((n2.Y == p.Y) && (n2.X > p.X))))
{
if (angle < 180)
{
type = "Start";
}
else
{
type = "Split";
}
}
else if (((p.Y < n1.Y) || ((p.Y == n1.Y) && (p.X > n1.Y))) && ((p.Y < n2.Y) || ((p.Y == n2.Y) && (p.X > n2.X))))
{
if (angle < 180)
{
type = "End";
}
else
{
type = "Merge";
}
}
else
{
type = "Regular";
}
EventPoint ev = new EventPoint(polygons[0].lines[i].Start, i, type, polygons[0].lines[i].End);
Q.Add(ev);
EventPoint prev;
if (i != (polygons[0].lines.Count - 1))
{
prev = new EventPoint(polygons[0].lines[i].Start, i, type, polygons[0].lines[i].End);
prev_event.Add(i + 1, prev);
}
else
{
prev = new EventPoint(polygons[0].lines[i].Start, i, type, polygons[0].lines[i].End);
prev_event.Add(0, prev);
}
}
while (Q.Count != 0)
{
EventPoint ev = Q.First();
Y = ev.point.Y;
if (ev.event_type == "Start")
{
helper.Add(ev.index, ev);
T.Add(ev);
}
else if (ev.event_type == "End")
{
if (ev.index - 1 >= 0)
{
if (helper[ev.index - 1].event_type == "Merge")
{
outLines.Add(new Line(ev.point, helper[ev.index - 1].point));
}
T.Remove(helper[ev.index - 1]);
}
}
else if (ev.event_type == "Merge")
{
// if (ev.index - 1 >= 0)
//{
EventPoint ev2 = helper[ev.index - 1];
if (ev2.event_type == "Merge")
{
outLines.Add(new Line(ev.point, ev2.point));
}
EventPoint prev = prev_event[ev.index];
T.Remove(prev);
//}
KeyValuePair <EventPoint, EventPoint> temp = new KeyValuePair <EventPoint, EventPoint>(T.DirectUpperAndLower(ev).Key, T.DirectUpperAndLower(ev).Value);
if (temp.Value != null)
{
if (helper[temp.Value.index].event_type == "Merge")
{
outLines.Add(new Line(ev.point, helper[temp.Value.index].point));
}
helper[temp.Value.index] = ev;
}
}
else if (ev.event_type == "Split")
{
KeyValuePair <EventPoint, EventPoint> temp = new KeyValuePair <EventPoint, EventPoint>(T.DirectUpperAndLower(ev).Key, T.DirectUpperAndLower(ev).Value);
if (temp.Value != null)
{
outLines.Add(new Line(ev.point, helper[temp.Value.index].point));
helper[temp.Value.index] = ev;
}
helper[ev.index] = ev;
T.Add(ev);
}
else
{
var y = ev.edge.Y;
if (ev.point.Y > y)
{
if (ev.index - 1 >= 0)
{
if (helper[ev.index - 1].event_type == "Merge")
{
outLines.Add(new Line(ev.point, helper[ev.index - 1].point));
}
T.Remove(prev_event[ev.index]);
}
helper.Add(ev.index, ev);
T.Add(ev);
}
else
{
KeyValuePair <EventPoint, EventPoint> temp = new KeyValuePair <EventPoint, EventPoint>(T.DirectUpperAndLower(ev).Key, T.DirectUpperAndLower(ev).Value);
if (temp.Value != null)
{
if (helper[temp.Value.index].event_type == "Merge")
{
outLines.Add(new Line(ev.point, helper[temp.Value.index].point));
helper[temp.Value.index] = ev;
}
}
}
}
Q.Remove(ev);
}
}