Standard Library procedure that scales athree-dimensional unit cube into the viewing area.
SCALE3D does not use explicit parameters, but rather modifies the system variable !P.T for use as the implicit input and output parameters. Eight three-dimensional data points are created at the vertices of the three-dimensional unit cube. These eight points are transformed by !P.T. The system is translated to bring the minimum (X, Y, Z) point to the origin, and then scaled to make each coordinate's maximum value equal to 1.
