
Display using XFree86-DGA extension
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. manpage:: 7 display-dga

Synopsis
--------

::

  display-dga: [-noinput] [-nocursor] [-physz==>sizex>,<sizey>[dpi]]
               [<display>]


Description
-----------


Uses the XFree86 DGA extension to do fullscreen direct framebuffer
access on X servers which support this.  For systems without kernel
framebuffer support, the program must be run as root for this target
to be able to mmap `/dev/mem`.


Options
-------

``-noinput``
    XF86DGA events sent to the window are not captured and merged with
    any other LibGII input sources.  This allows one to take input
    from raw devices without receiving duplicate events should X also
    be configured to use the device.

``-nocursor``
    Normal behavior of display-x and display-xlib is to create a small
    dot mouse cursor pixmap which is visible when the mouse is
    positioned over the window containing the visual.  This can get in
    the way of mouse cursors implemented by the application.  With
    this option, you will not see an X mouse cursor when it is over
    the visual.

``-physz==<sizex>,<sizey>[dpi]``
    This option will override the physical screen size reported by the
    X server, which affects applications which wish to remain
    resolution independent.  :p:`sizex`, :p:`sizey` are the x,y size
    of the screen in millimeters, unless the optional ``dpi`` string
    is affixed, in which case, they represent resolution in
    dots-per-inch.  Yes, there are two equals signs there, for reasons
    of compatibility with other targets.

:p:`display`
    The X display to connect to, otherwise defaults to the display
    specified in `DISPLAY`.


Environment Variables
---------------------

`GGI_DGA_FBDEV`
    specifies a framebuffer device to mmap instead of `/dev/mem`. This
    allows you to use the DGA target without root privileges!


Features
--------


- DirectBuffer always available.
- Some operations may be accelerated depending on the X server
- Multiple frames
- Panning
