1X11::Protocol::Ext::ComUpsoesritCeo(n3t)ributed Perl DocXu1m1e:n:tPartoitooncol::Ext::Composite(3)
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6 X11::Protocol::Ext::Composite - off-screen window contents
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9 use X11::Protocol;
10 my $X = X11::Protocol->new;
11 $X->init_extension('Composite')
12 or print "Composite extension not available";
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14 $X->CompositeRedirectWindow ($mywindow, 'Automatic');
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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.
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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.
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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.
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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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39 The following requests are made available with an "init_extension()",
40 as per "EXTENSIONS" in X11::Protocol.
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42 my $is_available = $X->init_extension('Composite');
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44 Composite 0.1
45 "($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 $server_minor is what the server will do, which
50 might be less than requested (but not more than).
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52 Actually the X.org server circa 1.10 will return a higher minor
53 version than the client requests.
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55 The current code supports up to 0.3 and the intention is to
56 automatically negotiate in "init_extension()" if/when necessary.
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58 "$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.
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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.
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68 $update is string "Automatic" or "Manual". Only one client at a
69 time may use Manual mode on a given $window (normally a "composite
70 manager" program).
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72 Redirection is a per-client setting and is automatically
73 unredirected if the client disconnects. An unredirect when not
74 redirected is a "BadValue" error. Off-screen storage remains in
75 effect while at least one current client has requested it.
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77 "$X->CompositeCreateRegionFromBorderClip ($region, $window)"
78 Create $region (a new XID) as a server-side region object
79 initialized to, umm, something about $window and its current border
80 or visible parts or whatnot.
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82 Region objects are from XFIXES 2.0 (X11::Protocol::Ext::XFIXES).
83 "CompositeCreateRegionFromBorderClip()" can be used without
84 "init_extension()" of XFIXES, but there's not much which can be
85 done with a region except through XFIXES.
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87 Composite 0.2
88 "$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).
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93 my $pixmap = $X->new_rsrc;
94 $X->CompositeNameWindowPixmap ($window, $pixmap);
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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 $window is mapped
99 and redirected again later then it has a new off-screen storage and
100 a new "CompositeNameWindowPixmap()" must be called to get a new
101 pixmap for it.
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103 Composite 0.3
104 "$overlay_window = $X->CompositeGetOverlayWindow ($window)"
105 Return the composite overlay window for the screen of $window.
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107 This window covers the whole screen and is always above ordinary
108 windows but below any screen saver, and doesn't appear in a
109 "QueryTree()". It's created when the first client asks for it, and
110 shared by any further clients who ask.
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112 "$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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117 X11::Protocol, X11::Protocol::Ext::XFIXES,
118 X11::Protocol::Ext::DOUBLE_BUFFER
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120 "Composite Extension", Version 0.4, 2007-7-3,
121 /usr/share/doc/x11proto-composite-dev/compositeproto.txt.gz,
122 "http://cgit.freedesktop.org/xorg/proto/compositeproto/plain/compositeproto.txt"
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125 <http://user42.tuxfamily.org/x11-protocol-other/index.html>
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128 Copyright 2011, 2012, 2013, 2014, 2017 Kevin Ryde
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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.
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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.
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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 v5.32.1 2021-01-27 X11::Protocol::Ext::Composite(3)