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Computes relative position of Candidate input features relative to Base input features.

The geometry of a Candidate feature is restricted to point and area, while Base features can only be lines.

See the example below. The Base lines are considered to be oriented from the start point to the end point (digitization sense). A Candidate feature is:

  • located to the LEFT of a Base feature if looking down the Base line in the direction of the orientation (from start to finish);
  • located to the RIGHT if the Candidate is on the right of a Base feature;
  • UNDEFINED if the Base and Candidate features intersect, or if the Base feature has a single point.



Output Port

Before being sent out through the Output port, each Candidate feature will have a list of its relative positions to each of the Base features attached to it. Each element of the list has two pieces of information:

  • a "base_id" which identifies the base
  • the computed relative "position"

Base features are dropped after being used.




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



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Tags Keywords: relative position