///<summary>
/// Returns the boundary, or the empty geometry if this Geometry is empty.
///</summary>
///<remarks>For a discussion
/// of this function, see the OpenGIS Simple Features Specification. As stated in SFS
/// Section 2.1.13.1, "the boundary of a Geometry is a set of Geometries of the next lower dimension."</remarks>
///<returns>Returns the closure of the combinatorial boundary of this Geometry</returns>
public override Geometry GetBoundary()
{
if (IsEmpty())
{
return(_geometryFactory.CreateGeometryCollection(null));
}
//LineString[] allRings = new LineString[_geometries.Length];
ArrayList allRings = new ArrayList();
for (int i = 0; i < _geometries.Length; i++)
{
Polygon polygon = (Polygon)_geometries[i];
GeometryCollection rings = (GeometryCollection)polygon.GetBoundary();
for (int j = 0; j < rings.GetNumGeometries(); j++)
{
//allRings[j] = rings[j-i] as LineString;
allRings.Add(rings.GetGeometryN(j));
}
}
return(_geometryFactory.CreateMultiLineString(GeometryFactory.ToLineStringArray(allRings)));
}
/// <summary>
/// Converts a GeometryCollection to <GeometryCollection Text > format, then Appends it to the writer.
/// </summary>
/// <param name="geometryCollection">The GeometryCollection to process.</param>
/// <param name="writer">The output stream writer to Append to.</param>
protected void AppendGeometryCollectionText(GeometryCollection geometryCollection, TextWriter writer)
{
if (geometryCollection.IsEmpty())
{
}
else
{
for (int i = 0; i < geometryCollection.GetNumGeometries(); i++)
{
AppendGeometryTaggedText(geometryCollection.GetGeometryN(i), writer);
}
}
}
/// <summary>
/// Converts a GeometryCollection to <GeometryCollection Text > format, then Appends it to the writer.
/// </summary>
/// <param name="geometryCollection">The GeometryCollection to process.</param>
/// <param name="level"></param>
/// <param name="writer">The output stream writer to Append to.</param>
protected void AppendGeometryCollectionText(GeometryCollection geometryCollection, int level,
StringWriter writer)
{
if ( geometryCollection.IsEmpty() )
{
writer.Write("EMPTY");
}
else
{
int level2 = level;
writer.Write("(");
for (int i = 0; i < geometryCollection.GetNumGeometries(); i++)
{
if (i > 0)
{
writer.Write(", ");
level2 = level + 1;
}
//AppendGeometryTaggedText(geometryCollection.GetGeometryN(i), level2, writer);
AppendGeometryTaggedText(geometryCollection.GetGeometryN(i), level2, writer);
}
writer.Write(")");
}
}
private bool HasRepeatedPoint(GeometryCollection gc)
{
for (int i = 0; i < gc.GetNumGeometries(); i++)
{
Geometry g = (Geometry)gc.GetGeometryN(i);
if (HasRepeatedPoint(g)) return true;
}
return false;
}
private void AddCollection(GeometryCollection gc)
{
for (int i = 0; i < gc.GetNumGeometries(); i++)
{
Geometry g = (Geometry)gc.GetGeometryN(i);
Add(g);
}
}
private void CheckValid(GeometryCollection gc)
{
for (int i = 0; i < gc.GetNumGeometries(); i++)
{
Geometry g = gc.GetGeometryN(i);
CheckValid(g);
if (_validErr != null) return;
}
}
