.\" $Xorg: XdbeSwap.man,v 1.3 2000/08/17 19:41:55 cpqbld Exp $
.\"
.\" 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.
.\"
.\" $XFree86: xc/doc/man/Xext/dbe/XdbeSwap.man,v 3.5 2001/02/07 22:35:22 tsi Exp $
.\"
.TH XdbeSwapBuffers __libmansuffix__ __xorgversion__ "X FUNCTIONS"
.SH NAME
XdbeSwapBuffers - swaps front and back DBE buffers.
.SH SYNOPSIS
\&#include <X11/extensions/Xdbe.h>

Status XdbeSwapBuffers(
    Display      *dpy,
    XdbeSwapInfo *swap_info,
    int          num_windows)
.SH DESCRIPTION
This function swaps the front and back buffers for a list of windows.  The
argument
.I num_windows
specifies how many windows are to have their buffers
swapped; it is the number of elements in the
.I swap_info
array.  The argument
.I swap_info
specifies the information needed per window to do the swap.

The
.I XdbeSwapInfo
structure has the following fields:

     Window            swap_window
     XdbeSwapAction    swap_action

.I swap_window
specifies the window for which to swap buffers.
.I swap_action
specifies the swap action to use for this
.I swap_window.

.I swap_action
determines what will happen to the new back buffer of the
.I swap_window
it is paired with in the list in addition to making the old back buffer
become visible.  The defined actions are as follows:

.IP XdbeUndefined
The contents of the new back buffer become undefined.  This may be the most
efficient action since it allows the implementation to discard the contents of
the buffer if it needs to.
.IP XdbeBackground
The unobscured region of the new back buffer will be tiled with the
window background.  The background action allows devices to use a fast clear
capability during a swap.
.IP XdbeUntouched
The unobscured region of the new back buffer will be unmodified by the swap.
.IP XdbeCopied
The unobscured region of the new back buffer will be the contents of the old
back buffer
.SH ERRORS
.IP BadMatch
A non-double-buffered window was specified or a window was specified twice.
.IP BadWindow
An invalid window was specified.
.IP BadValue
An invalid swap action was specified.
.SH SEE ALSO
DBE,
.I XdbeAllocateBackBufferName(),
.I XdbeBeginIdiom(),
.I XdbeDeallocateBackBufferName(),
.I XdbeEndIdiom(),
.I XdbeFreeVisualInfo(),
.I XdbeGetBackBufferAttributes(),
.I XdbeGetVisualInfo(),
.I XdbeQueryExtension().