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LENS(1)

NAME

lens − interactive screen magnifier

SYNOPSIS

­lens

DESCRIPTION

­Lens presents a magnified view in its window of an arbitrary area on the screen.  The default magnification is 4 (showing each pixel as a 4×4 pixel block in lens’s window). This may be changed by typing a digit on the keyboard (with ­0 standing for 10), or by using the ­+ and ­- keys to increase or decrease the magnification by one unit.  The lower limit is ×1; the upper ×16. 

The interface to indicate what area to magnify is dictated by the mouse multiplexing rules of rio(1). Start by pressing mouse button 1 in the ­lens window and dragging, with the button pressed, to the center of the area to magnify.  ­Lens will update the display as the mouse moves.  Releasing the button freezes the ­lens display.  The magnified view is static—a snapshot, not a movie—but typing a space or ­.  key  in the ­lens window will refresh the display, as will changing the magnification. 

To make counting pixels easier, typing a ­g toggles whether a checkerboard grid is imposed on the magnified area. 

SOURCE

­/sys/src/cmd/lens.c

BUGS

There should be an easier way to indicate what to magnify. 

Plan 9  —  August 15, 2002

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026