///<summary>
/// Converts a linearring to be sure it is clockwise.
///</summary>
///<remarks>Normal form is a unique representation
/// for Geometry's. It can be used to test whether two Geometrys are equal in a way that is
/// independent of the ordering of the coordinates within them. Normal form equality is a stronger
/// condition than topological equality, but weaker than pointwise equality. The definitions for
/// normal form use the standard lexicographical ordering for coordinates. Sorted in order of
/// coordinates means the obvious extension of this ordering to sequences of coordinates.
///</remarks>
private void Normalize(LinearRing ring, bool clockwise)
{
if (ring.IsEmpty())
{
return;
}
Coordinates uniqueCoordinates = new Coordinates();
for (int i = 0; i < ring.GetNumPoints() - 1; i++)
{
uniqueCoordinates.Add(ring.GetCoordinateN(i)); // copy all but last one into uniquecoordinates
}
Coordinate minCoordinate = MinCoordinate(ring.GetCoordinates());
Scroll(uniqueCoordinates, minCoordinate);
Coordinates ringCoordinates = ring.GetCoordinates();
ringCoordinates.Clear();
ringCoordinates.AddRange(uniqueCoordinates);
ringCoordinates.Add(uniqueCoordinates[0].Clone()); // add back in the closing point.
if (_cgAlgorithms.IsCCW(ringCoordinates) == clockwise)
{
ReversePointOrder(ringCoordinates);
}
}
///<summary>
/// Returns this Geometry's vertices. Do not modify the array, as it may be the actual array stored
/// by this Geometry. The Geometries contained by composite Geometries must be Geometry's;
/// that is, they must implement get Coordinates.
///</summary>
///<returns>Returns the vertices of this Geometry.</returns>
public override Coordinates GetCoordinates()
{
Coordinates coords = new Coordinates();
if (IsEmpty())
{
return(coords);
}
coords.AddRange(_shell.GetCoordinates());
if (_holes != null)
{
for (int i = 0; i < _holes.Length; i++)
{
coords.AddRange(_holes[i].GetCoordinates());
}
}
return(coords);
}
///<summary>
/// Returns this Geometry's vertices. Do not modify the array, as it may be the actual array stored
/// by this Geometry. The Geometries contained by composite Geometries must be Geometry's;
/// that is, they must implement get Coordinates.
///</summary>
///<returns>Returns the vertices of this Geometry.</returns>
public override Coordinates GetCoordinates()
{
Coordinates coords = new Coordinates();
if( IsEmpty() )
{
return coords;
}
coords.AddRange( _shell.GetCoordinates() );
if(_holes != null)
{
for(int i = 0; i < _holes.Length; i++)
{
coords.AddRange( _holes[i].GetCoordinates() );
}
}
return coords;
}
