get_curvature

Calculates the curvature of the path at the point.

Optionally, returns the center of the osculating circle as well. The curvature is the inverse of the radius of the osculating circle.

Lines have a curvature of zero (indicating an osculating circle of infinite radius. In this case, the center is not modified.

Circles with a radius of zero have `INFINITY` as curvature

Note that certain points on a path may not have a single curvature, such as sharp turns. At such points, there are two curvatures -- the (limit of) the curvature of the path going into the point, and the (limit of) the curvature of the path coming out of it. The direction argument lets you choose which one to get.

<picture> <source srcset="curvature-dark.png" media="(prefers-color-scheme: dark)"> <img alt="Osculating circle" src="curvature-light.png"> </picture>

Parameters:

this	a `GskPathPoint`
path	the path that this is on
direction	the direction for which to return the curvature
center	Return location for the center of the osculating circle

Returns:

The curvature of the path at the given point