private void DeletePolygon(Polygon polygon)
{
polygons.Remove(polygon);
}
public void ClipPolygon(Polygon polygon)
{
Vertex v;
List <Vertex>[] verticesAddToThis = new List <Vertex> [Vertices.Count];
List <Vertex>[] verticesAddToPolygon = new List <Vertex> [polygon.Vertices.Count];
for (int i = 0; i < polygon.Vertices.Count; i++)
{
verticesAddToPolygon[i] = new List <Vertex>();
}
for (int i = 0; i < Vertices.Count; i++)
{
verticesAddToThis[i] = new List <Vertex>();
for (int j = 0; j < polygon.Vertices.Count; j++)
{
if ((v = this.GetIntersectionPoint(Vertices[i], Vertices[(i + 1) % Vertices.Count], polygon.Vertices[j], polygon.Vertices[(j + 1) % polygon.Vertices.Count])) != null)
{
verticesAddToThis[i].Add(v);
verticesAddToPolygon[j].Add(v);
}
}
}
List <Vertex> intersections = new List <Vertex>();
bool outVertex = false;
for (int i = 0, j = 0; j < Vertices.Count; i++, j++)
{
verticesAddToThis[i].Sort((v1, v2) =>
{
double l1 = this.GetLineLength(Vertices[j], v1);
double l2 = this.GetLineLength(Vertices[j], v2);
if (l1 < l2)
{
return(-1);
}
if (l1 == l2)
{
return(0);
}
return(1);
});
foreach (Vertex ve in verticesAddToThis[i])
{
j++;
Vertices.Insert(j, ve);
if (outVertex)
{
intersections.Add(ve);
outVertex = false;
}
else
{
outVertex = true;
}
}
}
for (int i = 0, j = 0; j < polygon.Vertices.Count; i++, j++)
{
verticesAddToPolygon[i].Sort((v1, v2) =>
{
double l1 = this.GetLineLength(polygon.Vertices[j], v1);
double l2 = this.GetLineLength(polygon.Vertices[j], v2);
if (l1 < l2)
{
return(-1);
}
if (l1 == l2)
{
return(0);
}
return(1);
});
polygon.Vertices.InsertRange(j + 1, verticesAddToPolygon[i]);
j += verticesAddToPolygon[i].Count;
}
List <Vertex> newVertices = new List <Vertex>();
while (intersections.Count > 0)
{
int index = Vertices.FindIndex(ve => ve == intersections[0]);
Vertex vertex = Vertices[index];
bool thisList = true;
newVertices.Add(vertex);
while (true)
{
if (thisList)
{
index = (index + 1) % Vertices.Count;
vertex = Vertices[index];
if (vertex.Intersection)
{
if (vertex == intersections[0])
{
break;
}
intersections.Remove(vertex);
thisList = false;
index = polygon.Vertices.FindIndex(ve => ve == vertex);
}
}
else
{
index = (index + 1) % polygon.Vertices.Count;
vertex = polygon.Vertices[index];
if (vertex.Intersection)
{
if (vertex == intersections[0])
{
break;
}
intersections.Remove(vertex);
thisList = true;
index = Vertices.FindIndex(ve => ve == vertex);
}
}
newVertices.Add(vertex);
}
intersections.RemoveAt(0);
}
Vertices = newVertices;
}