Elongation is a measure of how long the polygon is in relation to its width. The perfect circle has the minimal elongation equal to 1.0, while the upper bound doesn't exist. The operation internally approximates the polygon with an ellipse, and then computes the result as: Where L denotes the longer axis of the approximating ellipse, and S denotes the shorter one.

Note that if the input path is not a valid polygon (i.e. it has at least one self-intersection), the computation may lead to results that are not intuitive.

This filter can throw an exception to report error. Read how to deal with errors in Error Handling.

List of possible exceptions:

This filter is available on Advanced Complexity Level.

• PolygonCircularity – Computes the area of a polygon divided by the area of a circle having the same feature.

• RegionElongation – Computes the elongation factor of a region ( perfect circle has minimal elongation equal 1.0 ).