This is a Mixin Interface returned by some properties of the manip Interface. It provides methods to get intersections with a manipulator plane.
Mixin Interface: (manip.msXYPlane)
.normal : point3 by value : Read
Returns the normal of a plane.
.point : point3 by value : Read
Return the point that the plane passes through.
.planeConstant : float : Read
Return the value of the plane constant. This is the value of "D" in the equation that defines the plane:
Ax + By +Cz + D = 0
intersectionPoint is In and Out parameter
Intersects the given ray with the plane. Returns true on success. The intersection point is set in the "intersectionPoint" value passes by reference, which must be initialized to a Point3 value in advance.
Returns the plane that is most orthogonal to the given ray. This means the plane that is most "square" to the view direction.