public HalfEdge(Vertex a_Vertex)
{
// Using new here prevents reference equality. Is it really necessary to copy?
m_Origin = new Vertex(a_Vertex.X, a_Vertex.Y, a_Vertex.Ownership);
Triangle = null;
Twin = null;
Next = null;
Prev = null;
}
protected void AddVertex(Triangle a_Triangle, Vertex a_Vertex)
{
m_Vertices.Add(a_Vertex);
m_Triangles.Remove(a_Triangle);
HalfEdge h1 = a_Triangle.HalfEdge;
HalfEdge h2 = h1.Next;
HalfEdge h3 = h2.Next;
HalfEdge h4 = new HalfEdge(h1.Origin);
HalfEdge h5 = new HalfEdge(h2.Origin);
HalfEdge h6 = new HalfEdge(h3.Origin);
HalfEdge h7 = new HalfEdge(a_Vertex);
HalfEdge h8 = new HalfEdge(a_Vertex);
HalfEdge h9 = new HalfEdge(a_Vertex);
m_HalfEdges.AddRange(new List<HalfEdge>() { h4, h5, h6, h7, h8, h9 });
h4.Twin = h7;
h7.Twin = h4;
h5.Twin = h8;
h8.Twin = h5;
h6.Twin = h9;
h9.Twin = h6;
// Set all next
h1.Next = h5;
h5.Prev = h1;
h5.Next = h7;
h7.Prev = h5;
h7.Next = h1;
h1.Prev = h7;
h2.Next = h6;
h6.Prev = h2;
h6.Next = h8;
h8.Prev = h6;
h8.Next = h2;
h2.Prev = h8;
h3.Next = h4;
h4.Prev = h3;
h4.Next = h9;
h9.Prev = h4;
h9.Next = h3;
h3.Prev = h9;
m_Triangles.Add(new Triangle(h1));
m_Triangles.Add(new Triangle(h2));
m_Triangles.Add(new Triangle(h3));
}
private void LegalizeEdge(Vertex a_Vertex, HalfEdge a_HalfEdge, Triangle a_Triangle)
{
if (a_Vertex == null || a_HalfEdge == null || a_Triangle == null)
{
Debug.LogError("Invalid call to LegalizeEdge");
return;
}
Vertex v1, v2, v3;
try
{
// Points to test
v1 = a_HalfEdge.Twin.Next.Next.Origin;
v2 = a_HalfEdge.Next.Twin.Next.Next.Origin;
v3 = a_HalfEdge.Next.Next.Twin.Next.Next.Origin;
}
catch (NullReferenceException)
{
Debug.LogError("Null pointers in call to LegalizeEdge");
return;
}
if (v1 == null || v2 == null || v3 == null)
{
Debug.LogError("Invalid halfedge in call to LegalizeEdge");
return;
}
if (a_Triangle.InsideCircumcenter(v1) || a_Triangle.InsideCircumcenter(v2) || a_Triangle.InsideCircumcenter(v3))
{
HalfEdge h1 = a_HalfEdge.Twin.Next.Twin;
HalfEdge h2 = a_HalfEdge.Twin.Prev.Twin;
Flip(a_HalfEdge);
LegalizeEdge(a_Vertex, h1.Twin, h1.Twin.Triangle);
LegalizeEdge(a_Vertex, h2.Twin, h2.Twin.Triangle);
}
}
public void DrawTriangle(Triangle t, Color c)
{
DrawTriangle(t.Point1, t.Point2, t.Point3, c);
}
public void DrawPolygon(Triangle t, Color c)
{
var plist = new List<Point>()
{
t.Point1,
t.Point2,
t.Point3
};
DrawPolygon(plist,c);
}