Compute the cartesian plane coordinates of a point in world space.

Input parameters:

1. Pt → Point in world XYZ space.
2. Pl → Plane describing the local cartesian coordinate system.

Output parameters:

1. X → X coordinate of the point in the plane coordinate system.
2. Y → Y coordinate of the point in the plane coordinate system.
3. Z → Z coordinate of the point in the plane coordinate system.