CenterLineReplacer
Replaces an area feature with its medial axis or a straight skeleton. This transformer works best with long, narrow areas.
Output Ports
The centerline of the input feature will be output via this port.
Features that cannot be replaced by their centerline will be output via this port.
Rejected features will have an fme_rejection_code attribute with the value INVALID_GEOMETRY.
Parameters
Medial Axis: The geometry of an area feature is replaced by its medial axis. The medial axis is the subset of the straight skeleton that does not include any edges that share a vertex with the original area.
Straight Skeleton: The geometry of an area feature is replaced by its straight skeleton (angular bisector network). All edges that share a vertex with the original area are removed.
Note: In either of these modes, the algorithm may take a long time to run on large or complex input features.
Usage Notes
- Unexpected output may result if input polygons self-intersect or have duplicate vertices.
- Because Z coordinates are not considered in either algorithm, all features processed by this function are forced to 2D.
- If non-area features are passed to this transformer, they will not be changed, and they are logged with a warning.
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Donuts that contain holes that touch will produce incorrect output.
- If vertices are very close together unexpected output may occur.
Example
Editing Transformer Parameters
Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click beside the applicable parameter. For more information, see Transformer Parameter Menu Options.
Transformer Categories
Related Transformers
When combined with the Tester, this transformer enables FME to perform area generalization operations.
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Tags Keywords: abstraction simplification simplify centerline centreline CentreLineReplacer