/// <summary>
/// Reads the next shape
/// </summary>
/// <returns></returns>
public IGeometry ReadNext(int RecordNumber)
{
IntPtr pShape = ShapeLib.SHPReadObject(_shapePointer, RecordNumber);
ShapeLib.SHPObject shpObject = new ShapeLib.SHPObject();
Marshal.PtrToStructure(pShape, shpObject);
double[] x = new double[shpObject.nVertices];
Marshal.Copy(shpObject.padfX, x, 0, x.Length);
double[] y = new double[shpObject.nVertices];
Marshal.Copy(shpObject.padfY, y, 0, y.Length);
double[] z = new double[shpObject.nVertices];
Marshal.Copy(shpObject.padfZ, z, 0, z.Length);
int[] partstarts = null;
if (shpObject.nParts > 0)
{
partstarts = new int[shpObject.nParts];
Marshal.Copy(shpObject.paPartStart, partstarts, 0, partstarts.Length);
}
ShapeLib.SHPDestroyObject(pShape);
IGeometry geom = null;
switch (type)
{
case ShapeLib.ShapeType.NullShape:
break;
case ShapeLib.ShapeType.MultiPoint:
case ShapeLib.ShapeType.MultiPointZ:
case ShapeLib.ShapeType.MultiPointM:
case ShapeLib.ShapeType.PointM:
case ShapeLib.ShapeType.PointZ:
case ShapeLib.ShapeType.Point:
geom = new XYPoint(x[0], y[0]);
break;
case ShapeLib.ShapeType.PolyLineM:
case ShapeLib.ShapeType.PolyLineZ:
case ShapeLib.ShapeType.PolyLine:
geom = new XYPolyline();
for (int i = 0; i < x.Length; i++)
{
((XYPolyline)geom).Points.Add(new XYPoint(x[i], y[i]));
}
break;
case ShapeLib.ShapeType.PolygonM:
case ShapeLib.ShapeType.PolygonZ:
case ShapeLib.ShapeType.Polygon:
if (partstarts.Count() == 1)
{
geom = new XYPolygon();
for (int i = 0; i < x.Length; i++)
{
((XYPolygon)geom).Points.Add(new XYPoint(x[i], y[i]));
}
((XYPolygon)geom).Points.Reverse();
}
else
{
geom = new MultiPartPolygon();
//foreach (var partstart in partstarts.Reverse())
//{
// var poly = new XYPolygon();
// for (int i = end; i > partstart; i--)
// poly.Points.Add(new XYPoint(x[i], y[i]));
// end = partstart;
// ((MultiPartPolygon)geom).Polygons.Add(poly);
//}
for (int j = 0; j < partstarts.Count(); j++)
{
int end;
if (j < partstarts.Count() - 1)
{
end = partstarts[j + 1];
}
else
{
end = x.Length;
}
var poly = new XYPolygon();
for (int i = partstarts[j]; i < end; i++)
{
poly.Points.Add(new XYPoint(x[i], y[i]));
}
poly.Points.Reverse();
((MultiPartPolygon)geom).Polygons.Add(poly);
}
}
break;
case ShapeLib.ShapeType.MultiPatch:
break;
default:
break;
}
return(geom);
}