As in the 2D case, this is specified by a Window volume in World
Coordinates, and a Viewport volume in Normalized Device Coordinates.
The Normalization Clip is controlled as for GKS-2D
(see section on Page 
).
The calls are:
CALL GSW3(TNR, WN) CALL GSV3(TNR, VP)where WN and VP are real arrays of dimension 6 containing (XMIN, XMAX, YMIN, YMAX, ZMIN, ZMAX).