LENS(1) 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 stand-
ing 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 chang-
ing the magnification.
To make counting pixels easier, typing a g toggles whether a
checkerboard grid is imposed on the magnified area.
Button 3 brings up a menu of actions.
SOURCE
/sys/src/cmd/lens.c
BUGS
There should be an easier way to indicate what to magnify.
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