An intersection point is stored in the go_intersection_point structure.
It has two curve hangers and a “parameter” property which expresses the parameter
of the point position on the first curve. If the geometry of the curves changes,
the intersection is positioned to the intersection closest to the parameter position.
It has one hanger for the point position.
The type is GOT_INTERSECTION_POINT and the subtype is GOST_INTERSECTION_POINT.