#### Kink

A kink is a point where a curve dramatically changes direction. The corners of a rectangle are kinks. Kinks may also happen at the points where curvature dramatically changes. For example a rounded rectangle has kinks where the line segments turn into arcs.

The red points mark the locations of kinks in the curves.

Surfaces extruded from curves will have kinks at the same location as the kinks in the input curve.