/// <summary>
/// The validate method check if the XYPolyline is valid. The checks
/// made are:
/// - is number of points >= 3
/// - is the length of all line segments positiv
/// - do any lines cross
/// - is the area positiv
/// Exception is raised if the constraints are not met.
/// </summary>
public new void Validate()
{
if (Points.Count < 3)
{
throw new System.Exception("Number of vertices in polygon element is less than 3.");
}
if (GetArea() <= 0)
{
throw new System.Exception("Area of polygon is negative or zero. XYPolygons must be ordered counter clockwise.");
}
for (int j = 0; j < Points.Count; j++)
{
if (GetLine(j).GetLength() == 0)
{
throw new System.Exception("Length of line segment no: " +
j.ToString() + " (0-based) of XYPolygon is zero.");
}
}
for (int j = 0; j < Points.Count; j++)
{
for (int m = 0; m < j; m++)
{
if (XYGeometryTools.DoLineSegmentsIntersect(GetLine(j), GetLine(m)))
{
throw new System.Exception("Line no: " + j.ToString() + " and line no: " +
m.ToString() + " of XYPolygon crosses.");
}
}
}
}
