calib-touch

Graphics and Screen4.0 (8.x)Screen Graphics Subsystem Developer's GuideAPIProgrammingUtilities

Calibrate a touchscreen

This utility can only be used on resistive touch displays. If your touch display is capacitive, refer to the Calibrating touch section of this guide.

Syntax:

calib-touch [-config-file=config_file]
            [-display=display_id]
            [-exit-on-timeout]
            [-format=pixel_format]
            [-interval=swap_interval]
            [-pos=x,y]
            [-recalibrate]
            [-sample-limit=sample]
            [-size=widthxheight]
            [-verbose=level]
            [-zorder=zorder]

Runs on:

QNX OS

Options:

-config-file=config_file
Set an alternative configuration filename, as a string (default is /etc/system/config/calib.hostname). This calibration tool requires access to write a configuration file. If /etc/system/config is on a read-only filesystem, then you will need to specify a different path and filename so that calib-touch has permissions to write the configuration file.
-display=display_id
Specify which display the window will appear on by using display_id. You can specify display_id as one of the following:
  • an integer that identifies the display
  • an ID string that identifies the name of the display (id_string)
Whether by integer or by string, the display that you specify using display_id must be one of the displays that you've configured in the display subsections of the winmgr section in your configuration file (e.g., graphics.conf).

If you don't have any display subsections configured, or if you don't specify the display option, then calib-touch uses the default display.

-exit-on-timeout
Exit this application after 5 seconds of inactivity on each calibration screen, or 30 seconds of inactivity on the final calibration screen. Otherwise, the application restarts the calibration procedure.
-format=pixel_format
Set the pixel format, as a string, of the window (default is the pixel format assigned by Screen Graphics Subsystem). The pixel format can be one of the following strings:
  • rgba8888
  • rgbx8888
  • rgb565
-interval=swap_interval
Set the swap interval, as an integer (default is 1). The swap interval is the minimum number of vsync periods between image updates.
-pos=x,y
Set the position, using integer x and y coordinates, of the viewport (default is 0, 0).
-recalibrate
Perform a calibration despite the existence of a calibration file. The existing calibration file will be overwritten. You may need to recalibrate if you make any changes related to the touch device (e.g., changing your display or display resolution).
-sample-limit=sample
Set the number of samples, as an integer, for each target (default is 10).
-size=widthxheight
Set the size, using integer values for width and height, of the viewport (default is fullscreen).
-verbose=level
Set the verbosity level, as an integer (default is 0).
-zorder=zorder
Set the z-order, as an integer, of the window (default is 0).

Description:

The calib-touch utility is a command-line tool that's used to calibrate a touchscreen. Once the touchscreen is successfully configured, the calib-touch utility saves a configuration file at /etc/system/config/calib.hostname.

Prior to starting the touch calibration, ensure that you have an appropriate begin mtouch section in your /etc/system/config/mtouch.conf file to define your touch device.

To run the calibration tool:

  1. Ensure that screen is running.
  2. Ensure that mtouch is running.
  3. Run calib-touch from either your starup script or from a shell.
  4. Touch the bull's-eye targets on each of the display screens.
  5. Touch the Accept button to finish calibration.

You can use the Esc key to exit the calibration tool at any time.

Examples:

Calibrate for fullscreen:

calib-touch
Figure 1First calibration screen


Figure 2Second calibration screen


Figure 3Third calibration screen


Figure 4Final calibration screen


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