IntersectPath Command
 IntersectPath( <Line>, <Polygon> )

Creates the intersection path between line and polygon.
IntersectPath(a, triangle)
creates a segment between the first and second intersection point of line a and
polygon triangle.
 IntersectPath( <Polygon>, <Polygon> )

Creates the intersection polygon between two given polygons.
IntersectPath(quadrilateral, triangle)
creates a new polygon as intersection of the two given polygons.
The new polygon can either be a quadrilateral, a pentagon or a hexagon. This depends on the position of the vertices of the given polygons. 
 IntersectPath( <Plane>, <Polygon> )

Creates the intersection path between plane and polygon.
IntersectPath(a, triangle)
creates a segment between the first and second intersection point of plane a and
polygon triangle in the plane of the polygon.
 IntersectPath( <Plane>, <Quadric> )

Creates the intersection path between plane and quadric.
IntersectPath(a, sphere)
creates a circle as intersection between plane a and quadric sphere.
See also Intersect and IntersectConic commands. 