/// <summary>
/// Computes the geometric union of a <see cref="IEnumerable{Geometry}"/><para/>
/// If no input geometries were provided but a <see cref="GeometryFactory"/> was provided,
/// an empty <see cref="GeometryCollection"/> is returned.
/// </summary>
/// <param name="geoms">A collection of geometries</param>
/// <param name="geomFact">The geometry factory to use if the collection is empty</param>
/// <returns>The union of the geometries
/// or an empty GEOMETRYCOLLECTION</returns>
public static Geometry Union(IEnumerable <Geometry> geoms, GeometryFactory geomFact)
{
var op = new UnaryUnionOp(geoms, geomFact);
return(op.Union());
}
/// <summary>Constructs a unary union operation for a <see cref="Geometry"/>
/// (which may be a <see cref="GeometryCollection"/>).
/// </summary>
/// <param name="geom">A geometry to union</param>
/// <returns>The union of the elements of the geometry
/// or an empty GEOMETRYCOLLECTION</returns>
public static Geometry Union(Geometry geom)
{
var op = new UnaryUnionOp(geom);
return(op.Union());
}
/// <summary>
/// Computes the geometric union of a <see cref="IEnumerable{Geometry}"/>
/// </summary>
/// <param name="geoms">A collection of geometries</param>
/// <returns>The union of the geometries,
/// or <c>null</c> if the input is empty</returns>
public static Geometry Union(IEnumerable <Geometry> geoms)
{
var op = new UnaryUnionOp(geoms);
return(op.Union());
}
