void CreateLocalTriangulationsBoundary(List <Tuple <Edge, TriangleBranch> > boundary,
TriangleBranch previousBranch, Edge vertice, Vertex point)
{
if (vertice.MirrorOut != null)
{
VertexCircleRelation relation = vertice.MirrorOut.NextIn.EndVertex.
IsRelativeToCircle(vertice.EndVertex, point, vertice.StartVertex);
if (relation == VertexCircleRelation.Outside ||
relation == VertexCircleRelation.Cocircular)
{
boundary.Add(new Tuple <Edge, TriangleBranch>(vertice, previousBranch));
}
else
{
var branch = new TriangleBranch(vertice.MirrorOut.IncludingTriangle, previousBranch);
CreateLocalTriangulationsBoundary(boundary, branch, vertice.MirrorOut.NextIn, point);
CreateLocalTriangulationsBoundary(boundary, branch, vertice.MirrorOut.NextIn.NextIn, point);
_triangles.Remove(vertice.MirrorOut.IncludingTriangle);
}
}
else
{
boundary.Add(new Tuple <Edge, TriangleBranch>(vertice, previousBranch));
}
}
Tuple <Edge, Edge> AddSlice(Tuple <Edge, TriangleBranch> bound, Vertex point)
{
Edge vertice = bound.Item1;
TriangleBranch branch = bound.Item2;
var slice = new Triangle(vertice, point, 0, true);
do
{
int j = 0;
while (j < branch.Node.VerticesIncluded.Count)
{
Vertex pointToInclude = branch.Node.VerticesIncluded[j];
VertexVectorOrientation o1 = pointToInclude.IsRelativeToLine(vertice.NextIn),
o2 = pointToInclude.IsRelativeToLine(vertice.NextIn.NextIn);
if ((o2 == VertexVectorOrientation.ToTheLeftOf ||
o2 == VertexVectorOrientation.Colinear) &&
o1 == VertexVectorOrientation.ToTheLeftOf)
{
slice.VerticesIncluded.Add(pointToInclude);
branch.Node.VerticesIncluded.Remove(pointToInclude);
}
else
{
j++;
}
}
branch = branch.PreviousNode;
}while (branch != null);
_triangles.Add(slice);
if (vertice.StartVertex == _m && vertice.EndVertex == _k)
{
_rightExtremeTriangle = slice;
}
return(new Tuple <Edge, Edge>(slice.Edges[2], slice.Edges[1]));
}
void Triangulate()
{
#region Local Fields
Edge firstVertice, secondVertice = null;
TriangleBranch containingTriangleRoot = new TriangleBranch(),
mirrorContainingTriangleRoot = new TriangleBranch();
var boundary = new List <Tuple <Edge, TriangleBranch> >();
Tuple <Edge, Edge> adjacentVertices = null;
#endregion // End of Local Fields
#region Rearrange data (I)
_points.Sort(_yComparer);
double xmin = _points.Min(p => p.X),
xmax = _points.Max(p => p.X),
ymin = _points[0].Y,
ymax = _points[_points.Count - 1].Y,
xo = (xmax + xmin) / 2D,
yo = (ymax + ymin) / 2D,
xdis = Math.Floor(xo),
ydis = Math.Floor(yo);
foreach (Vertex point in _points)
{
point.X -= xdis;
point.Y -= ydis;
}
xmin -= xdis;
ymin -= ydis;
xo -= xdis;
yo -= ydis;
#endregion // End of Rearrange data (I)
#region Create container triangle
double radious = (RadiousIncreaseByPercent + 1) * Math.Sqrt(Math.Pow(xo - xmin, 2) + Math.Pow(yo - ymin, 2)),
diam = 2 * radious,
height = radious * Math.Sqrt(3);
_k = new Vertex(xo, yo + diam, 0);
_l = new Vertex(xo - height, yo - radious, 0);
_m = new Vertex(xo + height, yo - radious, 0);
_triangles.Add(new Triangle(_k, _l, _m, new List <Vertex>(_points)));
_rightExtremeTriangle = _triangles[0];
#endregion // End of Create container triangle
#region Construct the mesh of points
foreach (Vertex point in _points)
{
Triangle containingTriangle = TriangleIncluding(point);
containingTriangle.VerticesIncluded.Remove(point);
containingTriangleRoot.Node = containingTriangle;
containingTriangleRoot.PreviousNode = null;
int i, j = i = 0;
bool found = false;
do
{
if (containingTriangle.Edges[i].EndVertex == _k)
{
found = true;
}
else
{
i++;
}
}while (!found);
found = false;
do
{
if (point.IsRelativeToLine(containingTriangle.Edges[j])
== VertexVectorOrientation.Colinear)
{
found = true;
}
else
{
j++;
}
}while (!found && j < 3);
if (found)
{
for (int k = i; k < i + 3; k++)
{
if (k == j)
{
if (containingTriangle.Edges[j].MirrorOut != null)
{
firstVertice = containingTriangle.Edges[j].MirrorOut;
CreateLocalTriangulationsBoundary(boundary, containingTriangleRoot, firstVertice.NextIn, point);
mirrorContainingTriangleRoot.Node = firstVertice.IncludingTriangle;
mirrorContainingTriangleRoot.PreviousNode = null;
CreateLocalTriangulationsBoundary(boundary, mirrorContainingTriangleRoot, firstVertice.NextIn.NextIn, point);
_triangles.Remove(firstVertice.IncludingTriangle);
}
else
{
boundary.Add(new Tuple <Edge, TriangleBranch>(containingTriangle.Edges[j], containingTriangleRoot));
}
}
else
{
CreateLocalTriangulationsBoundary(boundary, containingTriangleRoot, containingTriangle.Edges[k % 3], point);
}
}
}
else
{
for (j = i; j < i + 3; j++)
{
CreateLocalTriangulationsBoundary(boundary, containingTriangleRoot, containingTriangle.Edges[j % 3], point);
}
}
_triangles.Remove(containingTriangle);
Tuple <Edge, Edge> previousAdjacentVertices = AddSlice(boundary[0], point);
firstVertice = previousAdjacentVertices.Item1;
for (i = 1; i < boundary.Count; i++)
{
adjacentVertices = AddSlice(boundary[i], point);
adjacentVertices.Item1.ConnectWithMirror(previousAdjacentVertices.Item2);
previousAdjacentVertices = adjacentVertices;
}
adjacentVertices.Item2.ConnectWithMirror(firstVertice);
boundary.Clear();
}
#endregion // End of Construct the mesh of points
#region Envelope in closed curved boundary
EdgesRing closedBoundary = GetTriangulationsClosedBoundary();
closedBoundary.CurvePath();
closedBoundary.Triangulate(_triangles);
#endregion // End of Envelope in closed curved boundary
#region Apply edge constrains
if (!(_constrains == null || _constrains.Count == 0))
{
foreach (Tuple <Vertex, Vertex> constrain in _constrains)
{
if (!_points.Contains(constrain.Item1, _pComparer) ||
!_points.Contains(constrain.Item2, _pComparer))
{
continue;
}
List <Tuple <EdgesPath, EdgesPath> > sequencesPairs = GetSequences(constrain.Item1, constrain.Item2);
if (sequencesPairs == null)
{
continue;
}
foreach (Tuple <EdgesPath, EdgesPath> pair in sequencesPairs)
{
firstVertice = null;
if (pair.Item1.Path.Count > 0)
{
firstVertice = pair.Item1.Triangulate(_triangles);
}
if (pair.Item2.Path.Count > 0)
{
secondVertice = pair.Item2.Triangulate(_triangles);
}
if (firstVertice != null && secondVertice != null)
{
firstVertice.ConnectWithMirror(secondVertice);
}
}
}
}
#endregion // End of Apply edge constrains
#region Rearrange data (II)
foreach (Vertex point in _points)
{
point.X += xdis;
point.Y += ydis;
}
#endregion // End of Rearrange data (II)
}