# InnerPolygon

InnerPolygon[poly]

gives the inner polygon of the polygon poly.

# Details • InnerPolygon is also known as inner ring or hole.
• Typically used to decompose a polygon as a difference of simple polygons, even when the original construction of the polygon was using crossing curves etc.
• InnerPolygon is defined by the canonicalization performed in CanonicalizePolygon.
• • InnerPolygon gives a polygon of the form Polygon[{p1,p2,}, {{i1,i2,},}], where pk are explicit coordinates and ik are integer indexes referring to coordinates in the list {p1,p2,}.
• If poly is a polygon without a hole, then the result is an EmptyRegion object.

# Examples

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## Basic Examples(1)

Get the inner polygon of a Polygon:

## Scope(6)

InnerPolygon works on polygons:

Triangle:

Rectangle:

InnerPolygon works on polygons with GeoPosition:

Polygons with GeoGridPosition:

Polygon with holes:

Polygons with disconnected components:

Polygons in :

## Properties & Relations(1)

InnerPolygon of a simple polygon is an empty polygon: