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.\"
.\"
.\" Copyright © 2013 Keith Packard
.\"
.\" Permission to use, copy, modify, distribute, and sell this software and its
.\" documentation for any purpose is hereby granted without fee, provided that
.\" the above copyright notice appear in all copies and that both that copyright
.\" notice and this permission notice appear in supporting documentation, and
.\" that the name of the copyright holders not be used in advertising or
.\" publicity pertaining to distribution of the software without specific,
.\" written prior permission. The copyright holders make no representations
.\" about the suitability of this software for any purpose. It is provided "as
.\" is" without express or implied warranty.
.\"
.\" THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
.\" INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
.\" EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
.\" CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
.\" DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
.\" TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
.\" OF THIS SOFTWARE.
.\"
.de TQ
.br
.ns
.TP \\$1
..
.TH XPresentQueryCapabilities __libmansuffix__ __xorgversion__
.SH NAME
XPresentQueryCapabilities \- query capabilities of a CRTC
.SH SYNTAX
\&#include <X11/extensions/Xpresent.h>
.nf
.sp
uint32_t XPresentQueryCapabilities \^(\^Display *\fIdisplay\fP, XID \fItarget\fP\^)\^;
.fi
.SH DESCRIPTION
.B XPresentQueryCapabilities
returns a bitmask of the supported capabilities for the target CRTC. If
\fItarget\fP is a CRTC, then it is used as the target CRTC. If
\fItarget\fP is a WINDOW, then the target CRTC is selected by the
X server from among the CRTCs on the screen specified by the window.
.PP
\fBPresentCapabilityAsync\fP means that the target device can flip
the scanout buffer mid-frame instead of waiting for a vertical
blank interval. The precise latency between the flip request
and the actual scanout transition is not defined by this
specification, but is intended to be no more than a few
scanlines.
.PP
\fBPresentCapabilityFence\fP means that the target device can take
advantage of SyncFences in the \fBPresent\fP operations to improve
GPU throughput. The driver must operate correctly in the
absence of fences, but may have reduced performance. Using
fences for drivers not advertising this capability should have
no performance impact.
.PP
\fBPresentCapabilityUST\fP means that the target device can scanout
the image at an arbitrary UST time value, and is not driven by
a periodic scanout timer. Applications specifying UST times for
.BR XPresentPixmap (__libmansuffix__)
can expect that their image will appear to
the user within a short amount of time from that specified in
the request. The precise accuracy of the scanout time is not
defined by the extension, but is expected to be on the order
of milliseconds or less.
.SH SEE ALSO
.BR Xpresent (__libmansuffix__),
.BR XPresentNotifyMSC (__libmansuffix__),
.BR XPresentPixmap (__libmansuffix__),
.BR XPresentSelectInput (__libmansuffix__)
.SH AUTHORS
Keith Packard, Intel
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