Home Man
Today's Posts

Linux & Unix Commands - Search Man Pages

X11R7.4 - man page for xeviqueryextension (x11r4 section 3)

XEVI(3) 				   X FUNCTIONS					  XEVI(3)

       XeviQueryExtension,  XeviQueryVersion,  XeviGetVisualInfo  - X Extended Visual Information

       #include <X11/extensions/XEVI.h>

       Bool XeviQueryExtension (Display *dpy);

       Bool XeviQueryVersion (Display *dpy,
	   int *major_version_return,
	   int *minor_version_return);

       int XeviGetVisualInfo (Display *dpy, VisualID *visual,
	   int n_visual, ExtendedVisualInfo ** evi_return,
	   int * n_info_return);

       The X11 Extended Visual Information extension (EVI) allows a client to determine  informa-
       tion about core X visuals beyond what the core protocol provides.

       The EVI application programming library contains the interfaces described below.  With the
       exception of XeviQueryExtension, if any of these routines are called with a  display  that
       does  not  support the extension, the ExtensionErrorHandler (which can be set with XSetEx-
       tensionErrorHandler and functions the same way as XSetErrorHandler) will be called and the
       function will then return.

       XeviQueryExtension  returns True if the Extended Visual Information extension is available
       on the given display.  A client must call XeviQueryExtension before calling any other  EVI
       function  in  order  to negotiate a compatible protocol version; otherwise the client will
       get undefined behavior (EVI may or may not work).

       XeviQueryVersion returns True if the request succeeded; the values of the major and  minor
       protocol  version  supported  by  the  server  are  returned  in  major_version_return and

       XeviGetVisualInfo returns a list of ExtendedVisualInfo  structures  that  describe  visual
       information  beyond  that  supported by the core protocol. This includes layer information
       relevant for systems supporting overlays and/or	underlay  planes,  and	information  that
       allows  applications  better  to determine the level of hardware support for multiple col-
       ormaps. XeviGetVisualInfo returns Success if successful, or an X error otherwise.  If  the
       argument visual is NULL, then information for all visuals of all screens is returned. Oth-
       erwise, it's a pointer to a list of visuals  for  which	extended  visual  information  is
       desired.   n_visual  is	the number of elements in the array visual.  evi_return returns a
       pointer to a list of ExtendedVisualInfo. When done, the client should free the list  using
       XFree.  n_info_return returns the number of elements in the array evi_return.

       The ExtendedVisualInfo structure has the following fields:
	    VisualID	    core_visual_id
	    int 	    screen
	    int 	    level
	    unsigned int    transparency_type
	    unsigned int    transparency_value
	    unsigned int    min_hw_colormaps
	    unsigned int    max_hw_colormaps
	    unsigned int    num_colormap_conflicts
	    VisualID *	    colormap_conflicts

       The  combination  of  core_visual_id  and  screen number uniquely specify the visual being

       level returns the level number for the visual, 0 for normal planes, > 0 for overlays, <	0
       for underlays.

       transparency_type  returns  the	type of transparency supported by the visual. XEVI_TRANS-
       PARENCY_NONE if there are no transparent pixels,  XEVI_TRANSPARENCY_PIXEL  if  the  visual
       supports  a  transparent  pixel, XEVI_TRANSPARENCY_MASK if the visual supports transparent

       transparency_value returns the  pixel/plane  value  to  set  for  transparency  if  trans-
       parency_type isn't XEVI_TRANSPARENCY_NONE.

       min_hw_colormaps  and  max_hw_colormaps	return the minimum and maximum number of hardware
       colormaps backing up the visual.

       num_colormap_conflicts returns the number of elements in colormap_conflicts.   This  array
       returns	a  list  of visuals that may cause conflicts in the use of the hardware colormap.
       For example, if a 12-bit hardware colormap is overloaded to support 8-bit  colormaps,  the
       corresponding 8-bit visuals would conflict with the 12-bit visuals.

       XeviGetVisualInfo  will return BadValue if passed an illegal visual ID, BadAccess if the X
       server does not respond, BadAlloc if there is a memory allocation failure.

X Version 11				  libXext 1.0.5 				  XEVI(3)

All times are GMT -4. The time now is 08:51 AM.

Unix & Linux Forums Content Copyrightę1993-2018. All Rights Reserved.
Show Password