Replaces arc or ellipse geometry with interpolated straight line segments.

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Typical Uses

  • Preparing geometry for transformation, reprojection, or formats where arcs are not supported

How does it work?

The ArcStroker receives features with vector geometry and converts any arcs to a series of interpolated line segments.

Ellipses are converted to polygons. Paths will have any arc segments stroked while passing through line segments unchanged.

The number of interpolated edges may be determined by:

  • Letting the ArcStroker choose a reasonable number (default)

  • Specifying an exact number of segments to create per arc (Stroke By > Number of Interpolated Edges)

  • Specifying the maximum distance the new line segments may be from the original arc position (Stroke By > Maximum Deviation)

This example shows a circular arc stroked with four (4) interpolated edges:


Usage Notes

  • Maximum deviation is a measurement in ground units. Features with a geographic (lat/long) coordinate system may need to be reprojected before using this option.

  • To reverse arc stroking, consider using the Curvefitter or ArcEstimator.

Creating and Modifying Arcs, Circles, and Ellipses

These transformers work with arcs in a variety of ways.


Input Ports

Output Ports


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.

Defining Values

There are several ways to define a value for use in a Transformer. The simplest is to simply type in a value or string, which can include functions of various types such as attribute references, math and string functions, and workspace parameters. There are a number of tools and shortcuts that can assist in constructing values, generally available from the drop-down context menu adjacent to the value field.

Dialog Options - Tables

Transformers with table-style parameters have additional tools for populating and manipulating values.


Processing Behavior


Feature Holding


Dependencies None
Aliases ClothoidStroker

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