public void PerformCascadedPolygonUnion()
{
var reader = new ShapefileReader("tnp_pol.shp");
var collection = reader.ReadAll().Where(e => e is IPolygon).ToList();
var u1 = collection[0];
for (var i = 1; i < collection.Count; i++)
{
u1 = SnapIfNeededOverlayOp.Overlay(u1, collection[i], SpatialFunction.Union);
}
var u2 = CascadedPolygonUnion.Union(collection);
if (!u1.Equals(u2))
{
Assert.Fail("failure");
}
}
/// <summary>
/// Computes a unary union with no extra optimization, and no short-circuiting.
/// </summary>
/// <remarks>
/// Due to the way the overlay operations are implemented, this is still efficient in the case of linear and puntal geometries.
/// </remarks>
/// <param name="g0">A geometry</param>
/// <returns>The union of the input geometry</returns>
private Geometry UnionNoOpt(Geometry g0)
{
var empty = _geomFact.CreatePoint();
return(SnapIfNeededOverlayOp.Overlay(g0, empty, SpatialFunction.Union));
}
protected override Geometry Overlay(Geometry geom0, Geometry geom1, SpatialFunction opCode)
{
return(SnapIfNeededOverlayOp.Overlay(geom0, geom1, opCode));
}
