Builds connections between donut holes with the outer boundary of a donut, resulting in a polygon-equivalent representation of the input donut.  

A single, connected path visits the boundary and each donut hole exactly once and guaranteed to not cross over itself completely if the input feature is properly oriented. This action is performed on all donuts contained in an input feature.

The transformer outputs unmodified features at the Invalid port when a feature contains a donut with faulty topology (such as a hole lying outside of an outer boundary).


The generated polygon boundary will have shared, overlapping boundary segments where the rings connect to each other.

Another example shows a county in Washington, USA, consisting of several islands. The islands are cut from an expanded bounding box, and the workspace converts the remaining donut into a polygon:



This transformer has no parameters.

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.

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