Copyright (c) 1995 Hewlett-Packard Company
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
HEWLETT-PACKARD COMPANY BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
Except as contained in this notice, the name of the Hewlett-Packard Company shall not
be used in advertising or otherwise to promote the sale, use or other
dealing in this Software without prior written authorization from the
Hewlett-Packard Company.
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
HEWLETT-PACKARD COMPANY BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
Except as contained in this notice, the name of the Hewlett-Packard Company shall not
be used in advertising or otherwise to promote the sale, use or other
dealing in this Software without prior written authorization from the
Hewlett-Packard Company.
XdbeGetVisualInfo __libmansuffix__ __xorgversion__ "X FUNCTIONS"
NAME
XdbeGetVisualInfo - Get dbe Visual Information
SYNOPSIS
#include <X11/extensions/Xdbe.h>
XdbeScreenVisualInfo *XdbeGetVisualInfo(
Display *dpy,
Drawable *screen_specifiers,
int *num_screens)
DESCRIPTION
This function returns information about which visuals support double
buffering. The argument
num_screens specifies how many elements there are
in the
screen_specifiers list. Each drawable in
screen_specifiers designates a
screen for which the supported visuals are being requested. If
num_screens is zero, information for all screens is requested. In this case, upon return
from this function,
num_screens will be set to the number of screens that were
found. If an error occurs, this function returns NULL, else it returns a
pointer to a list of
XdbeScreenVisualInfo structures of length
num_screens. The nth
element in the returned list corresponds to the nth drawable in the
screen_specifiers list, unless
num_screens was passed in with the value zero,
in which case the nth element in the returned list corresponds to the nth screen
of the server, starting with screen zero. The
XdbeScreenVisualInfo structure has the following fields:
int count
XdbeVisualInfo *visinfo
count specifies the number of items in
visinfo. visinfo specifies a list of visuals, depths, and performance hints for this screen.
The
XdbeVisualInfo structure has the following fields:
VisualID visual
int depth
int perflevel
visual specifies one visual ID that supports double-buffering.
depth specifies the depth of the visual.
perflevel is a performance hint.
The only operation defined on a
perflevel is comparison to a
perflevel of another visual on the same screen. The visual having the higher
perflevel is likely to have better double-buffering graphics performance than the visual
having the lower
perflevel. Nothing can be deduced from the following: the magnitude of the difference
of two
perflevels, a
perflevel value in isolation, or comparing
perflevels from different servers.
ERRORS
BadDrawable
One or more values passed in
screen_specifiers is not a valid drawable.
SEE ALSO
DBE,
XdbeAllocateBackBufferName(), XdbeBeginIdiom(), XdbeDeallocateBackBufferName(), XdbeEndIdiom(), XdbeFreeVisualInfo(), XdbeGetBackBufferAttributes(), XdbeQueryExtension(), XdbeSwapBuffers().