Method
GskPathPointget_curvature
since: 4.14
Declaration [src]
float
gsk_path_point_get_curvature (
const GskPathPoint* point,
GskPath* path,
GskPathDirection direction,
graphene_point_t* center
)
Description [src]
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.
Available since: 4.14
Parameters
path-
Type:
GskPathThe path that
pointis on.The data is owned by the caller of the method. direction-
Type:
GskPathDirectionThe direction for which to return the curvature.
center-
Type:
graphene_point_tReturn location for the center of the osculating circle.
The argument will be set by the function. The argument can be set to NULLby the method.The returned data is owned by the instance.