TOUCHCAL(8) TOUCHCAL(8)
NAME
touchcal - touch screen calibration
SYNOPSIS
touchcal
DESCRIPTION
Touchcal draws a cross-hair in each corner of the screen in
turn (clockwise from the lower left hand corner), and waits
each time for the user to touch the centre of the cross-hair
with the stylus. It then prompts with a final cross-hair in
the centre of the screen, and waits once more for the user
to touch its centre with the stylus. The process is
repeated until touchcal can calculate a transformation
matrix that consistently maps the touch panel to screen
coordinates. It then writes corresponding calibration com-
mands for touch(3) on its standard output, which can be
saved in a file on the device, perhaps provided in NVRAM by
tinyfs(3) or a file system in ftl(3).
Touchcal can be used both inside and outside the wm(1) envi-
ronment, allowing calibration when the system is ini-
tialised, and whilst the window system is running.
FILES
/dev/touchctl reset or read existing settings
SOURCE
/appl/cmd/touchcal.b
SEE ALSO
touch(3)
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