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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 one or more attributes in common.

The difference between the AnchoredSnapper and the Snapper is that anchor features are considered to be accurate and consequently do not move.

Output Ports




Usage Notes

A short cleanup step is performed after snapping. This step will remove duplicate points, and may create aggregates to preserve overlapping, directed segments.

Any feature that undergoes dimensional collapse as a result of being snapped will be logged as "degenerate" and dropped.  Dimensional collapse refers to a line or area that becomes a point, or an area that becomes a line.

Related Transformers

  • The Snapper seems to snap to the first suitable candidate that is found and then ignores the other possible candidates. If this is not what you're looking for, the CoordinateRounder may be useful instead. 
  • You can clean up a dataset by using a Snapper before trying more complex actions, such as building polygons. Other transformers that are often used in this context are the Extender and Intersector.
  • The AnchoredSnapper transformer provides slightly different functionality by identifying a set of features which will not be moved and will be snapped to by another set of features.


The example below illustrates end points of two line features snapping together.



The example below illustrates an endpoint and a vertex of a line snapping together.



The example below illustrates vertices of a segment snapping to another segment.


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

Geometric Operators

FME Licensing Level

FME Base edition and above

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