an example can be found on AMOSPro_Examples:Examples/H-7/Help_77.AMOS
Magnifies or reduces a section of the screen by ZOOMing in or out.
Zoom source,stx,sty,sbx,sby To destination,dtx,dty,dbx,dby
Takes an image from stx,sty to sby,sby and copies it to the region dtx,dty to dbx,dby. If the destination area is larger than the source, the image will be expanded in order to fit. If it's smaller, the image will be reduced.