X11::Protocol::Ext::Composite(3pm)

1X11::Protocol::Ext::ComUpsoesritCeo(n3t)ributed Perl DocXu1m1e:n:tPartoitooncol::Ext::Composite(3)
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NAME

6       X11::Protocol::Ext::Composite - off-screen window contents
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SYNOPSIS

9        use X11::Protocol;
10        my $X = X11::Protocol->new;
11        $X->init_extension('Composite')
12          or print "Composite extension not available";
13
14        $X->CompositeRedirectWindow ($mywindow, 'Automatic');
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DESCRIPTION

17       The Composite extension holds the full pixel contents of windows in
18       off-screen storage, ready for things like "CopyArea()".  Normally the
19       server only keeps the visible parts of a window, not areas overlapped
20       or obscured.
21
22       In "Automatic" mode the visible parts of a window are displayed on
23       screen as normal.  The off-screen storage is then a little like the
24       backing store feature, but just when one or more clients declare an
25       interest in the full content.
26
27       In "Manual" mode the window contents are not drawn on screen, only kept
28       off-screen.  This mode is for use by special "composite manager"
29       programs which might make a composite display (hence the name of the
30       extension) of the overlapping windows with partial-transparency or
31       shadowing effects.
32
33       There's nothing here to draw or combine to actually make a composite
34       window result.  When required that's done with the usual core protocol
35       drawing or with drawing extensions such as RENDER (see
36       X11::Protocol::Ext::RENDER).
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REQUESTS

39       The following requests are made available with an "init_extension()",
40       as per "EXTENSIONS" in X11::Protocol.
41
42           my $is_available = $X->init_extension('Composite');
43
44   Composite 0.1
45       "($server_major, $server_minor) = $X->CompositeQueryVersion
46       ($client_major, $client_minor)"
47           Negotiate a protocol version with the server.  $client_major and
48           $client_minor is what the client would like, the returned
49           $server_major and $server_minor is what the server will do, which
50           might be less than requested (but not more than).
51
52           Actually the X.org server circa 1.10 will return a higher minor
53           version than the client requests.
54
55           The current code supports up to 0.3 and the intention is to
56           automatically negotiate in "init_extension()" if/when necessary.
57
58       "$X->CompositeRedirectWindow ($window, $update)"
59       "$X->CompositeRedirectSubwindows ($window, $update)"
60       "$X->CompositeUnredirectWindow ($window, $update)"
61       "$X->CompositeUnredirectSubwindows ($window, $update)"
62           Enable or disable a redirect of $window to off-screen storage.
63
64           "Window()" acts on just the given $window.  "Subwindows()" acts on
65           $window and also any subwindows it has now or in the future.  The
66           root window cannot be redirected.
67
68           $update is string "Automatic" or "Manual".  Only one client at a
69           time may use Manual mode on a given $window (normally a "composite
70           manager" program).
71
72           Redirection is a per-client setting and is automatically
73           unredirected if the client disconnects.  An unredirect when not
74           redirected is a "BadValue" error.  Off-screen storage remains in
75           effect while at least one current client has requested it.
76
77       "$X->CompositeCreateRegionFromBorderClip ($region, $window)"
78           Create $region (a new XID) as a server-side region object
79           initialized to, umm, something about $window and its current border
80           or visible parts or whatnot.
81
82           Region objects are from XFIXES 2.0 (X11::Protocol::Ext::XFIXES).
83           "CompositeCreateRegionFromBorderClip()" can be used without
84           "init_extension()" of XFIXES, but there's not much which can be
85           done with a region except through XFIXES.
86
87   Composite 0.2
88       "$X->CompositeNameWindowPixmap ($window, $pixmap)"
89           Set $pixmap (a new XID) to refer to the off-screen storage of
90           $window.  $window must be viewable (mapped and all of its parents
91           mapped) and must be redirected (by any client).
92
93               my $pixmap = $X->new_rsrc;
94               $X->CompositeNameWindowPixmap ($window, $pixmap);
95
96           $pixmap is released with "FreePixmap()" in the usual way.  If
97           $window or a parent is unmapped then $pixmap continues to exist,
98           but it's association with $window is lost.  If $window is mapped
99           and redirected again later then it has a new off-screen storage and
100           a new "CompositeNameWindowPixmap()" must be called to get a new
101           pixmap for it.
102
103   Composite 0.3
104       "$overlay_window = $X->CompositeGetOverlayWindow ($window)"
105           Return the composite overlay window for the screen of $window.
106
107           This window covers the whole screen and is always above ordinary
108           windows but below any screen saver, and doesn't appear in a
109           "QueryTree()".  It's created when the first client asks for it, and
110           shared by any further clients who ask.
111
112       "$X->CompositeReleaseOverlayWindow ($window)"
113           Release the composite overlay window for the screen of $window.
114           When all clients release it the overlay window is destroyed.
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HOME PAGE

125       <http://user42.tuxfamily.org/x11-protocol-other/index.html>
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LICENSE

128       Copyright 2011, 2012, 2013, 2014, 2017 Kevin Ryde
129
130       X11-Protocol-Other is free software; you can redistribute it and/or
131       modify it under the terms of the GNU General Public License as
132       published by the Free Software Foundation; either version 3, or (at
133       your option) any later version.
134
135       X11-Protocol-Other is distributed in the hope that it will be useful,
136       but WITHOUT ANY WARRANTY; without even the implied warranty of
137       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
138       General Public License for more details.
139
140       You should have received a copy of the GNU General Public License along
141       with X11-Protocol-Other.  If not, see <http://www.gnu.org/licenses/>.
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145perl v5.34.0                      2022-01-21  X11::Protocol::Ext::Composite(3)

NAME

SYNOPSIS

DESCRIPTION

REQUESTS

SEE ALSO

HOME PAGE

LICENSE