/// <summary>
/// Gets the Voronoi cell around a site specified
/// by the origin of a QuadEdge.
/// </summary>
/// <remarks>
/// The userData of the polygon is set to be the <see cref="Coordinate" />
/// of the site. This allows attaching external
/// data associated with the site to this cell polygon.
/// </remarks>
/// <param name="qe">a quadedge originating at the cell site</param>
/// <param name="geomFact">a factory for building the polygon</param>
/// <returns>a polygon indicating the cell extent</returns>
public Polygon GetVoronoiCellPolygon(QuadEdge qe, GeometryFactory geomFact)
{
var cellPts = new List <Coordinate>();
var startQE = qe;
do
{
// Coordinate cc = circumcentre(qe);
// use previously computed circumcentre
var cc = qe.Rot.Orig.Coordinate;
cellPts.Add(cc);
// move to next triangle CW around vertex
qe = qe.OPrev;
} while (qe != startQE);
var coordList = new CoordinateList();
coordList.AddAll(cellPts, false);
coordList.CloseRing();
if (coordList.Count < 4)
{
Debug.WriteLine(coordList);
coordList.Add(coordList[coordList.Count - 1], true);
}
var pts = coordList.ToCoordinateArray();
var cellPoly = geomFact.CreatePolygon(geomFact.CreateLinearRing(pts));
var v = startQE.Orig;
cellPoly.UserData = v.Coordinate;
return(cellPoly);
}
/// <summary>
/// Gets the Voronoi cell around a site specified
/// by the origin of a QuadEdge.
/// </summary>
/// <remarks>
/// The userData of the polygon is set to be the <see cref="Coordinate" />
/// of the site. This allows attaching external
/// data associated with the site to this cell polygon.
/// </remarks>
/// <param name="qe">a quadedge originating at the cell site</param>
/// <param name="geomFact">a factory for building the polygon</param>
/// <returns>a polygon indicating the cell extent</returns>
public IPolygon GetVoronoiCellPolygon(QuadEdge qe, IGeometryFactory geomFact)
{
var cellPts = new List<Coordinate>();
QuadEdge startQE = qe;
do
{
// Coordinate cc = circumcentre(qe);
// use previously computed circumcentre
Coordinate cc = qe.Rot.Orig.Coordinate;
cellPts.Add(cc);
// move to next triangle CW around vertex
qe = qe.OPrev;
} while (qe != startQE);
var coordList = new CoordinateList();
coordList.AddAll(cellPts, false);
coordList.CloseRing();
if (coordList.Count < 4)
{
#if !PCL
Debug.WriteLine(coordList);
#endif
coordList.Add(coordList[coordList.Count - 1], true);
}
Coordinate[] pts = coordList.ToCoordinateArray();
IPolygon cellPoly = geomFact.CreatePolygon(geomFact.CreateLinearRing(pts), null);
Vertex v = startQE.Orig;
cellPoly.UserData = v.Coordinate;
return cellPoly;
}
