NAME

magnify − screen bitmap magnifier

DISCLAIMER

This program is furnished on an AS IS basis as a demonstration of TNT applications programming. 

SYNOPSIS

magnify

DESCRIPTION

Magnify is a NeWS/TNT demonstration program that implements a window containing a single canvas which provides a magnified (or reduced) view of any area on the screen.  The magnification (or reduction) is accomplished by obtaining a bitmap image of the desired area of the screen, then performing pixel replication (or merge) via the PostScript ‘scale’ operator. 
 
The degree of magnification (reduction) may be changed through the use of a pop-up menu.  The source location is chosen by pressing the Select mouse button over the magnification canvas, then moving the mouse cursor over the area to be displayed before releasing Select. The magnification canvas will dynamically to show the area under the cursor while the mouse is being dragged.

Magnify demonstrates the use of the Track service and simple menus in addition to the standard window header and footers.  It also demonstrates the use of the PostScript scale operator. 

Menu

Zoom In
Increase the magnification ratio.

Zoom Out
Reduce the magnification ratio.  Note that it is possible to reduce the magnification level below 1:1

ResetReset the magnification ratio to 2:1. 

BUGS

As the zoom level is reduced beyond the point where the entire screen occupies only a small portion of the magnify window, the server will allocate more and more memory to represent the off-screen areas.  It is possible to crash the server by zooming out far enough to exhaust virtual memory.

LEGAL STUFF

PostScript is a trademark of Adobe Systems, Inc. NeWS is a trademark of Sun Microsystems, Inc.

Sun Release 4.1  —  Last change: 02/01/91