FME Transformers: 2024.1

Categories
Geometries
Spatial Analysis
Related Transformers
AreaAmalgamator
AreaCalculator
AreaGapAndOverlapCleaner
AreaOnAreaOverlayer
Dissolver
DonutBridgeBuilder
DonutBuilder
DonutHoleExtractor
HoleCounter
LineCloser
LineOnAreaOverlayer
TopologyBuilder

AreaBuilder

Creates polygons from topologically correct linear features.

Jump to Configuration

Typical Uses

  • Creating polygons from linear features
  • Checking linear network topology

How does it work?

The AreaBuilder receives features with linear geometry (lines, paths, and polygons) and creates areas wherever the linework surrounds closed shapes.

Areas are output, as well as any geometry not used for area creation.

Attributes may be merged or dropped, or accumulated in a list attribute along with an optional direction attribute that records the orientation of the input features.

Output polygon boundaries may be either lines or paths that preserve the input segments. Where areas are contained within other areas, donuts may be created and the donut holes either output or discarded.

Stricter rules may be applied for successful area formation, including checking for continuous curve direction and internal edges (cycles).

Aggregate geometries are either deaggregated or rejected.

Z values are supported.

Preparing input features for the AreaBuilder

Input features must have clean topology or they will not be used and output as Incomplete. The AreaBuilder has snapping capability, but more pre-processing may be required.

Topology issues could be:

  • Features not terminating at intersections
  • Misaligned nodes
  • Overshoots/undershoots
  • Missing nodes at intersections

These transformers may be useful for pre-processing input features.

 

Use This For

Description

Snapper

Snapping together misaligned nodes with more options than the AreaBuilder’s built-in snapping.

Brings lines, segments, end points or vertex points of features together if they are within a certain distance of each other and (optionally) if they have attributes in common.

Intersector

Splitting intersecting features, adding new nodes where necessary.

Computes intersections between all input features, breaking lines and polygons wherever an intersection occurs/

Chopper

Chopping geometry into two-point lines, without adding any new nodes.

Chops line, arc, path, or area features into smaller features based on number of vertices or approximate length.

LineExtender

Adding length to undershoots (followed by an Intersector).

Extends line, arc, or path features at both ends by a specified length.

TopologyBuilder

Building full topology on input features, which includes intersecting them.

Computes topology on input point, line, and/or area features, and outputs significant nodes, edges, and faces with attributes describing topological relationships.

Examples

Usage Notes

  • As input features must be topologically correct for AreaBuilder to create polygons, it can be useful for checking topology.
  • The AreaBuilder has some snapping capability, but the Snapper provides more snapping options.

Creating and Modifying Area Features

These transformers work with polygons in a variety of ways.

Configuration

Input Ports

Output Ports

Parameters

Editing Transformer Parameters

Transformer parameters can be set by directly entering values, using expressions, or referencing other elements in the workspace such as attribute values or user parameters. Various editors and context menus are available to assist. To see what is available, click beside the applicable parameter.

For more information, see Transformer Parameter Menu Options.

Reference

Processing Behavior

Group-Based

Feature Holding

Yes

Dependencies None
Aliases Polygonizer PolygonBuilder
History  

FME Community

The FME Community is the place for demos, how-tos, articles, FAQs, and more. Get answers to your questions, learn from other users, and suggest, vote, and comment on new features.

Search for all results about the AreaBuilder on the FME Community.

 

Examples may contain information licensed under the Open Government Licence – Vancouver, Open Government Licence - British Columbia, and/or Open Government Licence – Canada.