Constructs an ortho-aligned rectangular clip boundary. Two diagonally opposite corners define the rectangle. 

Input segments that lie on the boundary are considered "inside." 

The clip boundary object can be constructed or set once and used repeatedly.

Public Sub New(
    firstCorner As Point2d, 
    secondCorner As Point2d
)

public ClipBoundary2d(
    Point2d firstCorner, 
    Point2d secondCorner
);