XSGISTEREO(3X11)	 X Version 11 (Release 6)     XSGISTEREO(3X11)



     NAME
	  XSGIStereoQueryExtension, XSGIStereoQueryVersion,
	  XSGIQueryStereoMode, XSGISetStereoMode, XSGISetStereoBuffer
	  - X SGI stereo functions

     SYNTAX
	  #include <X11/extensions/SGIStereo.h>

	  Bool XSGIStereoQueryExtension	(
	       Display * dpy,
	       int * first_event,
	       int * first_error);

	  Status XSGIStereoQueryVersion	(
	       Display * dpy,
	       int * major_version,
	       int * minor_version);

	  int XSGIQueryStereoMode(
	       Display * dpy,
	       Window win);

	  Status XSGISetStereoMode (
	       Display *dpy,
	       Window win,
	       unsigned	short height,
	       unsigned	short offset,
	       int mode);

	  Status XSGISetStereoBuffer (
	       Display *dpy,
	       Window win,
	       int buffer);

     ARGUMENTS
	  dpy	    Specifies the connection to	the X server.

	  first_event
		    Returns the	code of	the first custom event type
		    created by the extension.

	  first_error
		    Returns the	code of	the first custom error defined
		    by the extension.

	  major_version
		    Returns major version number for the extension.

	  minor_version
		    Returns minor version number for the extension.

	  win	    Specifies the window on whose screen you want to



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		    set	or inquire the stereo mode.

	  height
	  offset    Specify the	height of each stereo buffer, and the
		    vertical offset between each stereo	buffer.

	  mode	    Specifies the stereo mode to be set. Valid values
		    are	STEREO_OFF (0) to turn off stereo,
		    STEREO_BOTTOM (1) to turn on stereo	and use	the
		    bottom half	of the screen as the primary buffer,
		    STEREO_TOP (2) to turn on stereo and use the top
		    half of the	screen as the primary buffer.

	  buffer    Identifies which buffer the	GL will	render to.


     DESCRIPTION
	  XSGIStereoQueryExtension is used to check whether the	X
	  server supports the SGI Stereo extension.  If	the Stereo
	  extension is present,	this routine will return True. If the
	  extension involves additional	event types, the base event
	  type code is returned	in first_event.	Otherwise, zero	is
	  returned in first_event. If the extension involves
	  additional error codes, the base error code is returned in
	  first_error. Otherwise, zero is returned. If the SGI Stereo
	  extension is present,	you must still query the individual
	  screens to find out if they support the extension, using
	  XSGIQueryStereoMode.

	  XSGIStereoQueryVersion is used to get	the version number of
	  the Stereo extension supported by the	X server.

	  XSGIQueryStereoMode is used to query the server for the
	  current stereo mode. If the server supports the SGI Stereo
	  extension, but win's screen does not,	this routine will
	  return X_STEREO_UNSUPPORTED (-1). If win's screen supports
	  the SGI Stereo extension, this routine will return one of
	  STEREO_OFF (0), STEREO_BOTTOM	(1) or STEREO_TOP (2).

	  XSGIQueryStereoMode can generate BadDrawable.

	  XSGISetStereoMode is used to inform the X server that	full-
	  screen stereo	is being turned	on or off. It does not cause
	  the actual video timing to change. Rather, if	turning	on
	  stereo, this procedure informs the server that all future X
	  rendering is to be duplicated	from the primary buffer	to the
	  secondary buffer. Calling this procedure also	causes the
	  cursor to be restricted to the primary buffer. Non-stereo GL
	  clients will render to the left eye, with the	right eye
	  cleared to black.

	  Conversely, if turning off stereo, this procedure informs



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	  the server to	return to the normal state, with X rendering
	  allowed to the full screen and unrestricting the cursor.

	  If turning on	stereo,	height and offset describe the height
	  of each stereo buffer	and the	vertical offset	between
	  buffers. Typically, these values should be 492 and 532
	  respectively.	height and offset are ignored if turning off
	  stereo.

	  Stereo is turned off by setting mode to STEREO_OFF (0), and
	  is turned on by setting mode to STEREO_BOTTOM	or STEREO_TOP
	  (1 or	2 respectively). Setting mode to STEREO_BOTTOM causes
	  the bottom half of the screen	to become the primary buffer,
	  setting it to	STEREO_TOP causes the top half of the screen
	  to become the	primary	buffer.	 To switch from	using the top
	  half of the screen as	the primary buffer to using the	bottom
	  half of the screen as	the primary buffer, XSGISetStereoMode
	  should first be called with mode set to STEREO_OFF.

	  NOTE:	The application	will not normally call this procedure.
	  Instead, it will call	setmonitor, which will update both the
	  X server state and the actual	video format.

	  XSGISetStereoMode can	generate BadDrawable and BadRequest.

	  XSGISetStereoBuffer is used to inform	the X server of	which
	  eye buffer the GL will render	to next. The first time	it's
	  called for a window, it also informs the server that the
	  window is a stereo window.  buffer identifies	which buffer
	  to set up. Valid values are STEREO_BUFFER_LEFT and
	  STEREO_BUFFER_RIGHT. If stereo mode is turned	on (by calling
	  XSGISetStereoMode), a	call to	XSGISetStereoBuffer will cause
	  the X	server to set the clip and window origin appropriately
	  for the GL client.

	  XSGISetStereoBuffer can generate BadDrawable and BadValue
	  errors.

	  Applications calling one of these routines should link with
	  libXext.

     SEE ALSO
	       setmon, setmonitor, viewport, winset












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