PointOnAreaOverlayer

From fmepedia

PointOnAreaOverlayer is a Workbench Transformer.

Performs an overlay of points on areas. Using the group by option limits this to points and areas which have the selected attributes in common. If a list name is entered, a List will be constructed that holds all attributes of all points that fall within an area (and vice-versa).

The attribute _overlaps (default name, this can be changed) holds the number of overlapping objects.

Q) What does FME do when a point falls exactly on the line between polygons?

A) We always include points on the boundary as being in. So if a point is on the boundary of two polygons, it will be called "in". Always. For both of them.

Q) I have a lot of features to process, but not much memory. Is there a way of improving overlay performance?

A) With a Point on Area overlay the task can be carried out much more efficiently using the Clipper transformer. The Clipper also provides different options for a point falling exactly on a line (see above). See the Clipper page for information on how to use less memory using the "Clippers First" setting.