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-rw-r--r--libxcb/doc/Makefile.am42
-rw-r--r--libxcb/doc/Makefile.in377
-rw-r--r--libxcb/doc/tutorial/index.html4521
-rw-r--r--libxcb/doc/tutorial/xcb.css123
-rw-r--r--libxcb/doc/xcb.doxygen.in1253
5 files changed, 6316 insertions, 0 deletions
diff --git a/libxcb/doc/Makefile.am b/libxcb/doc/Makefile.am
new file mode 100644
index 000000000..19255197c
--- /dev/null
+++ b/libxcb/doc/Makefile.am
@@ -0,0 +1,42 @@
+
+EXTRA_DIST = \
+tutorial/index.html \
+tutorial/xcb.css \
+xcb.doxygen.in
+
+docdirs = $(srcdir)/tutorial
+
+if BUILD_DOCS
+
+docdirs += manual
+
+# rule to build documentation and copy necessary files
+manual:
+ doxygen xcb.doxygen
+
+# rules to clean
+clean-local:
+ rm -rf manual/
+
+endif
+
+all-local: $(docdirs)
+
+# rule to install the html documentation and tutorial in $(htmldir)
+install-data-local:
+ @if ! test -d "$(DESTDIR)$(htmldir)"; then \
+ echo "$(mkinstalldirs) '$(DESTDIR)$(htmldir)'"; \
+ $(mkinstalldirs) '$(DESTDIR)$(htmldir)'; \
+ fi
+ @for d in $(docdirs); do \
+ echo "cp -pR $$d '$(DESTDIR)$(htmldir)/'"; \
+ cp -pR $$d '$(DESTDIR)$(htmldir)/'; \
+ done
+
+uninstall-local:
+ @for d in $(docdirs); do \
+ d=`basename $$d`; \
+ echo "test ! -d '$(DESTDIR)$(htmldir)/'$$d || { find '$(DESTDIR)$(htmldir)/'$$d -type d ! -perm -200 -exec chmod u+w '{}' ';' && rm -rf '$(DESTDIR)$(htmldir)/'$$d; }"; \
+ test ! -d '$(DESTDIR)$(htmldir)/'$$d || { find '$(DESTDIR)$(htmldir)/'$$d -type d ! -perm -200 -exec chmod u+w '{}' ';' && rm -rf '$(DESTDIR)$(htmldir)/'$$d; }; \
+ done
+ rmdir "$(DESTDIR)$(htmldir)/" || true
diff --git a/libxcb/doc/Makefile.in b/libxcb/doc/Makefile.in
new file mode 100644
index 000000000..3eba71aaf
--- /dev/null
+++ b/libxcb/doc/Makefile.in
@@ -0,0 +1,377 @@
+# Makefile.in generated by automake 1.9.6 from Makefile.am.
+# @configure_input@
+
+# Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
+# 2003, 2004, 2005 Free Software Foundation, Inc.
+# This Makefile.in is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY, to the extent permitted by law; without
+# even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+# PARTICULAR PURPOSE.
+
+@SET_MAKE@
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+VPATH = @srcdir@
+pkgdatadir = $(datadir)/@PACKAGE@
+pkglibdir = $(libdir)/@PACKAGE@
+pkgincludedir = $(includedir)/@PACKAGE@
+top_builddir = ..
+am__cd = CDPATH="$${ZSH_VERSION+.}$(PATH_SEPARATOR)" && cd
+INSTALL = @INSTALL@
+install_sh_DATA = $(install_sh) -c -m 644
+install_sh_PROGRAM = $(install_sh) -c
+install_sh_SCRIPT = $(install_sh) -c
+INSTALL_HEADER = $(INSTALL_DATA)
+transform = $(program_transform_name)
+NORMAL_INSTALL = :
+PRE_INSTALL = :
+POST_INSTALL = :
+NORMAL_UNINSTALL = :
+PRE_UNINSTALL = :
+POST_UNINSTALL = :
+build_triplet = @build@
+host_triplet = @host@
+@BUILD_DOCS_TRUE@am__append_1 = manual
+subdir = doc
+DIST_COMMON = $(srcdir)/Makefile.am $(srcdir)/Makefile.in \
+ $(srcdir)/xcb.doxygen.in
+ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
+am__aclocal_m4_deps = $(top_srcdir)/acinclude.m4 \
+ $(top_srcdir)/configure.ac
+am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
+ $(ACLOCAL_M4)
+mkinstalldirs = $(install_sh) -d
+CONFIG_HEADER = $(top_builddir)/src/config.h
+CONFIG_CLEAN_FILES = xcb.doxygen
+SOURCES =
+DIST_SOURCES =
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+PACKAGE_STRING = @PACKAGE_STRING@
+PACKAGE_TARNAME = @PACKAGE_TARNAME@
+PACKAGE_VERSION = @PACKAGE_VERSION@
+PATH_SEPARATOR = @PATH_SEPARATOR@
+PKG_CONFIG = @PKG_CONFIG@
+RANLIB = @RANLIB@
+SET_MAKE = @SET_MAKE@
+SHELL = @SHELL@
+STRIP = @STRIP@
+VERSION = @VERSION@
+XCBPROTO_CFLAGS = @XCBPROTO_CFLAGS@
+XCBPROTO_LIBS = @XCBPROTO_LIBS@
+XCBPROTO_XCBINCLUDEDIR = @XCBPROTO_XCBINCLUDEDIR@
+XDMCP_CFLAGS = @XDMCP_CFLAGS@
+XDMCP_LIBS = @XDMCP_LIBS@
+XSLTPROC = @XSLTPROC@
+ac_ct_CC = @ac_ct_CC@
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+am__include = @am__include@
+am__leading_dot = @am__leading_dot@
+am__quote = @am__quote@
+am__tar = @am__tar@
+am__untar = @am__untar@
+bindir = @bindir@
+build = @build@
+build_alias = @build_alias@
+build_cpu = @build_cpu@
+build_os = @build_os@
+build_vendor = @build_vendor@
+datadir = @datadir@
+datarootdir = @datarootdir@
+docdir = @docdir@
+dvidir = @dvidir@
+exec_prefix = @exec_prefix@
+host = @host@
+host_alias = @host_alias@
+host_cpu = @host_cpu@
+host_os = @host_os@
+host_vendor = @host_vendor@
+htmldir = @htmldir@
+includedir = @includedir@
+infodir = @infodir@
+install_sh = @install_sh@
+libdir = @libdir@
+libexecdir = @libexecdir@
+localedir = @localedir@
+localstatedir = @localstatedir@
+mandir = @mandir@
+mkdir_p = @mkdir_p@
+oldincludedir = @oldincludedir@
+pdfdir = @pdfdir@
+prefix = @prefix@
+program_transform_name = @program_transform_name@
+psdir = @psdir@
+sbindir = @sbindir@
+sharedstatedir = @sharedstatedir@
+sysconfdir = @sysconfdir@
+target_alias = @target_alias@
+xcbincludedir = @xcbincludedir@
+EXTRA_DIST = \
+tutorial/index.html \
+tutorial/xcb.css \
+xcb.doxygen.in
+
+docdirs = $(srcdir)/tutorial $(am__append_1)
+all: all-am
+
+.SUFFIXES:
+$(srcdir)/Makefile.in: $(srcdir)/Makefile.am $(am__configure_deps)
+ @for dep in $?; do \
+ case '$(am__configure_deps)' in \
+ *$$dep*) \
+ cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh \
+ && exit 0; \
+ exit 1;; \
+ esac; \
+ done; \
+ echo ' cd $(top_srcdir) && $(AUTOMAKE) --foreign doc/Makefile'; \
+ cd $(top_srcdir) && \
+ $(AUTOMAKE) --foreign doc/Makefile
+.PRECIOUS: Makefile
+Makefile: $(srcdir)/Makefile.in $(top_builddir)/config.status
+ @case '$?' in \
+ *config.status*) \
+ cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh;; \
+ *) \
+ echo ' cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__depfiles_maybe)'; \
+ cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__depfiles_maybe);; \
+ esac;
+
+$(top_builddir)/config.status: $(top_srcdir)/configure $(CONFIG_STATUS_DEPENDENCIES)
+ cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh
+
+$(top_srcdir)/configure: $(am__configure_deps)
+ cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh
+$(ACLOCAL_M4): $(am__aclocal_m4_deps)
+ cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh
+xcb.doxygen: $(top_builddir)/config.status $(srcdir)/xcb.doxygen.in
+ cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@
+
+mostlyclean-libtool:
+ -rm -f *.lo
+
+clean-libtool:
+ -rm -rf .libs _libs
+
+distclean-libtool:
+ -rm -f libtool
+uninstall-info-am:
+tags: TAGS
+TAGS:
+
+ctags: CTAGS
+CTAGS:
+
+
+distdir: $(DISTFILES)
+ $(mkdir_p) $(distdir)/tutorial
+ @srcdirstrip=`echo "$(srcdir)" | sed 's|.|.|g'`; \
+ topsrcdirstrip=`echo "$(top_srcdir)" | sed 's|.|.|g'`; \
+ list='$(DISTFILES)'; for file in $$list; do \
+ case $$file in \
+ $(srcdir)/*) file=`echo "$$file" | sed "s|^$$srcdirstrip/||"`;; \
+ $(top_srcdir)/*) file=`echo "$$file" | sed "s|^$$topsrcdirstrip/|$(top_builddir)/|"`;; \
+ esac; \
+ if test -f $$file || test -d $$file; then d=.; else d=$(srcdir); fi; \
+ dir=`echo "$$file" | sed -e 's,/[^/]*$$,,'`; \
+ if test "$$dir" != "$$file" && test "$$dir" != "."; then \
+ dir="/$$dir"; \
+ $(mkdir_p) "$(distdir)$$dir"; \
+ else \
+ dir=''; \
+ fi; \
+ if test -d $$d/$$file; then \
+ if test -d $(srcdir)/$$file && test $$d != $(srcdir); then \
+ cp -pR $(srcdir)/$$file $(distdir)$$dir || exit 1; \
+ fi; \
+ cp -pR $$d/$$file $(distdir)$$dir || exit 1; \
+ else \
+ test -f $(distdir)/$$file \
+ || cp -p $$d/$$file $(distdir)/$$file \
+ || exit 1; \
+ fi; \
+ done
+check-am: all-am
+check: check-am
+all-am: Makefile all-local
+installdirs:
+install: install-am
+install-exec: install-exec-am
+install-data: install-data-am
+uninstall: uninstall-am
+
+install-am: all-am
+ @$(MAKE) $(AM_MAKEFLAGS) install-exec-am install-data-am
+
+installcheck: installcheck-am
+install-strip:
+ $(MAKE) $(AM_MAKEFLAGS) INSTALL_PROGRAM="$(INSTALL_STRIP_PROGRAM)" \
+ install_sh_PROGRAM="$(INSTALL_STRIP_PROGRAM)" INSTALL_STRIP_FLAG=-s \
+ `test -z '$(STRIP)' || \
+ echo "INSTALL_PROGRAM_ENV=STRIPPROG='$(STRIP)'"` install
+mostlyclean-generic:
+
+clean-generic:
+
+distclean-generic:
+ -test -z "$(CONFIG_CLEAN_FILES)" || rm -f $(CONFIG_CLEAN_FILES)
+
+maintainer-clean-generic:
+ @echo "This command is intended for maintainers to use"
+ @echo "it deletes files that may require special tools to rebuild."
+@BUILD_DOCS_FALSE@clean-local:
+clean: clean-am
+
+clean-am: clean-generic clean-libtool clean-local mostlyclean-am
+
+distclean: distclean-am
+ -rm -f Makefile
+distclean-am: clean-am distclean-generic distclean-libtool
+
+dvi: dvi-am
+
+dvi-am:
+
+html: html-am
+
+info: info-am
+
+info-am:
+
+install-data-am: install-data-local
+
+install-exec-am:
+
+install-info: install-info-am
+
+install-man:
+
+installcheck-am:
+
+maintainer-clean: maintainer-clean-am
+ -rm -f Makefile
+maintainer-clean-am: distclean-am maintainer-clean-generic
+
+mostlyclean: mostlyclean-am
+
+mostlyclean-am: mostlyclean-generic mostlyclean-libtool
+
+pdf: pdf-am
+
+pdf-am:
+
+ps: ps-am
+
+ps-am:
+
+uninstall-am: uninstall-info-am uninstall-local
+
+.PHONY: all all-am all-local check check-am clean clean-generic \
+ clean-libtool clean-local distclean distclean-generic \
+ distclean-libtool distdir dvi dvi-am html html-am info info-am \
+ install install-am install-data install-data-am \
+ install-data-local install-exec install-exec-am install-info \
+ install-info-am install-man install-strip installcheck \
+ installcheck-am installdirs maintainer-clean \
+ maintainer-clean-generic mostlyclean mostlyclean-generic \
+ mostlyclean-libtool pdf pdf-am ps ps-am uninstall uninstall-am \
+ uninstall-info-am uninstall-local
+
+
+# rule to build documentation and copy necessary files
+@BUILD_DOCS_TRUE@manual:
+@BUILD_DOCS_TRUE@ doxygen xcb.doxygen
+
+# rules to clean
+@BUILD_DOCS_TRUE@clean-local:
+@BUILD_DOCS_TRUE@ rm -rf manual/
+
+all-local: $(docdirs)
+
+# rule to install the html documentation and tutorial in $(htmldir)
+install-data-local:
+ @if ! test -d "$(DESTDIR)$(htmldir)"; then \
+ echo "$(mkinstalldirs) '$(DESTDIR)$(htmldir)'"; \
+ $(mkinstalldirs) '$(DESTDIR)$(htmldir)'; \
+ fi
+ @for d in $(docdirs); do \
+ echo "cp -pR $$d '$(DESTDIR)$(htmldir)/'"; \
+ cp -pR $$d '$(DESTDIR)$(htmldir)/'; \
+ done
+
+uninstall-local:
+ @for d in $(docdirs); do \
+ d=`basename $$d`; \
+ echo "test ! -d '$(DESTDIR)$(htmldir)/'$$d || { find '$(DESTDIR)$(htmldir)/'$$d -type d ! -perm -200 -exec chmod u+w '{}' ';' && rm -rf '$(DESTDIR)$(htmldir)/'$$d; }"; \
+ test ! -d '$(DESTDIR)$(htmldir)/'$$d || { find '$(DESTDIR)$(htmldir)/'$$d -type d ! -perm -200 -exec chmod u+w '{}' ';' && rm -rf '$(DESTDIR)$(htmldir)/'$$d; }; \
+ done
+ rmdir "$(DESTDIR)$(htmldir)/" || true
+# Tell versions [3.59,3.63) of GNU make to not export all variables.
+# Otherwise a system limit (for SysV at least) may be exceeded.
+.NOEXPORT:
diff --git a/libxcb/doc/tutorial/index.html b/libxcb/doc/tutorial/index.html
new file mode 100644
index 000000000..c5404263f
--- /dev/null
+++ b/libxcb/doc/tutorial/index.html
@@ -0,0 +1,4521 @@
+<!DOCTYPE html public "-//W3C//DTD HTML 4.01 Transitional//EN"
+"http://www.w3.org/TR/html4/loose.dtd">
+
+<html>
+
+<head>
+ <title>Basic Graphics Programming With The XCB Library</title>
+ <meta http-equiv="content-type" content="text/html; charset=iso-8859-1">
+ <link href="xcb.css" rel="stylesheet" type="text/css">
+</head>
+
+<body>
+ <div class="title">
+ Basic Graphics Programming With The XCB Library
+ </div>
+ <div class="toc">
+ <ol>
+ <li><a class="section" href="#intro">Introduction</a>
+ <li><a class="section" href="#Xmodel">The client and server model of the X window system</a>
+ <li><a class="section" href="#asynch">GUI programming: the asynchronous model</a>
+ <li><a class="section" href="#notions">Basic XCB notions</a>
+ <ol>
+ <li><a class="subsection" href="#conn">The X Connection</a>
+ <li><a class="subsection" href="#requestsreplies">Requests and replies: the Xlib killers</a>
+ <li><a class="subsection" href="#gc">The Graphics Context</a>
+ <li>Object handles
+ <li>Memory allocation for XCB structures
+ <li><a class="subsection" href="#events">Events</a>
+ </ol>
+ <li><a class="section" href="#use">Using XCB-based programs</a>
+ <ol>
+ <li><a class="subsection" href="#inst">Installation of XCB</a>
+ <li><a class="subsection" href="#comp">Compiling XCB-based programs</a>
+ </ol>
+ <li><a class="section" href="#openconn">Opening and closing the connection to an X server</a>
+ <li><a class="section" href="#screen">Checking basic information about a connection</a>
+ <li><a class="section" href="#helloworld">Creating a basic window - the "hello world" program</a>
+ <li><a class="section" href="#drawing">Drawing in a window</a>
+ <ol>
+ <li><a class="subsection" href="#allocgc">Allocating a Graphics Context</a>
+ <li><a class="subsection" href="#changegc">Changing the attributes of a Graphics Context</a>
+ <li><a class="subsection" href="#drawingprim">Drawing primitives: point, line, box, circle,...</a>
+ </ol>
+ <li><a class="section" href="#xevents">X Events</a>
+ <ol>
+ <li><a class="subsection" href="#register">Registering for event types using event masks</a>
+ <li><a class="subsection" href="#loop">Receiving events: writing the events loop</a>
+ <li><a class="subsection" href="#expose">Expose events</a>
+ <li><a class="subsection" href="#userinput">Getting user input</a>
+ <ol>
+ <li><a class="subsubsection" href="#mousepressrelease">Mouse button press and release events</a>
+ <li><a class="subsubsection" href="#mousemvnt">Mouse movement events</a>
+ <li><a class="subsubsection" href="#mouseenter">Mouse pointer enter and leave events</a>
+ <li><a class="subsubsection" href="#focus">The keyboard focus</a>
+ <li><a class="subsubsection" href="#keypress">Keyboard press and release events</a>
+ </ol>
+ <li><a class="subsection" href="#eventex">X events: a complete example</a>
+ </ol>
+ <li><a class="section" href="#font">Handling text and fonts</a>
+ <ol>
+ <li><a class="subsection" href="#fontstruct">The Font structure</a>
+ <li><a class="subsection" href="#openingfont">Opening a Font</a>
+ <li><a class="subsection" href="#assigningfont">Assigning a Font to a Graphic Context</a>
+ <li><a class="subsection" href="#drawingtext">Drawing text in a drawable</a>
+ <li><a class="subsection" href="#fontcompleteexample">Complete example</a>
+ </ol>
+ <li>Windows hierarchy
+ <ol>
+ <li>Root, parent and child windows
+ <li>Events propagation
+ </ol>
+ <li><a class="section" href="#wm">Interacting with the window manager</a>
+ <ol>
+ <li><a class="subsection" href="#wmprop">Window properties</a>
+ <li><a class="subsection" href="#wmname">Setting the window name and icon name</a>
+ <li>Setting preferred window size(s)
+ <li>Setting miscellaneous window manager hints
+ <li>Setting an application's icon
+ <li>Obeying the delete-window protocol
+ </ol>
+ <li><a class="section" href="#winop">Simple window operations</a>
+ <ol>
+ <li><a class="subsection" href="#winmap">Mapping and unmapping a window</a>
+ <li><a class="subsection" href="#winconf">Configuring a window</a>
+ <li><a class="subsection" href="#winmove">Moving a window around the screen</a>
+ <li><a class="subsection" href="#winsize">Resizing a window</a>
+ <li><a class="subsection" href="#winstack">Changing windows stacking order: raise and lower</a>
+ <li>Iconifying and de-iconifying a window
+ <li><a class="subsection" href="#wingetinfo">Getting informations about a window</a>
+ </ol>
+ <li><a class="section" href="#usecolor">Using colors to paint the rainbow</a>
+ <ol>
+ <li><a class="subsection" href="#colormap">Color maps</a>
+ <li><a class="subsection" href="#colormapalloc">Allocating and freeing Color Maps</a>
+ <li><a class="subsection" href="#alloccolor">Allocating and freeing a color entry</a>
+ <li>Drawing with a color
+ </ol>
+ <li><a class="section" href="#pixmaps">X Bitmaps and Pixmaps</a>
+ <ol>
+ <li><a class="subsection" href="#pixmapswhat">What is a X Bitmap ? An X Pixmap ?</a>
+ <li>Loading a bitmap from a file
+ <li>Drawing a bitmap in a window
+ <li><a class="subsection" href="#pixmapscreate">Creating a pixmap</a>
+ <li><a class="subsection" href="#pixmapsdraw">Drawing a pixmap in a window</a>
+ <li><a class="subsection" href="#pixmapsfree">Freeing a pixmap</a>
+ </ol>
+ <li><a class="subsection" href="#mousecursor">Messing with the mouse cursor</a>
+ <ol>
+ <li><a class="subsection" href="#mousecursorcreate">Creating and destroying a mouse cursor</a>
+ <li><a class="subsection" href="#mousecursorset">Setting a window's mouse cursor</a>
+ <li><a class="subsection" href="#mousecursorexample">Complete example</a>
+ </ol>
+ <li><a class="subsection" href="#translation">Translation of basic Xlib functions and macros</a>
+ <ol>
+ <li><a class="subsection" href="#displaystructure">Members of the Display structure</a>
+ <ol>
+ <li><a class="subsection" href="#ConnectionNumber">ConnectionNumber</a>
+ <li><a class="subsection" href="#DefaultScreen">DefaultScreen</a>
+ <li><a class="subsection" href="#QLength">QLength</a>
+ <li><a class="subsection" href="#ScreenCount">ScreenCount</a>
+ <li><a class="subsection" href="#ServerVendor">ServerVendor</a>
+ <li><a class="subsection" href="#ProtocolVersion">ProtocolVersion</a>
+ <li><a class="subsection" href="#ProtocolRevision">ProtocolRevision</a>
+ <li><a class="subsection" href="#VendorRelease">VendorRelease</a>
+ <li><a class="subsection" href="#DisplayString">DisplayString</a>
+ <li><a class="subsection" href="#BitmapUnit">BitmapUnit</a>
+ <li><a class="subsection" href="#BitmapBitOrder">BitmapBitOrder</a>
+ <li><a class="subsection" href="#BitmapPad">BitmapPad</a>
+ <li><a class="subsection" href="#ImageByteOrder">ImageByteOrder</a>
+ </ol>
+ <li><a class="subsection" href="#screenofdisplay">ScreenOfDisplay related functions</a>
+ <ol>
+ <li><a class="subsection" href="#ScreenOfDisplay">ScreenOfDisplay</a>
+ <li><a class="subsection" href="#DefaultScreenOfDisplay">DefaultScreenOfDisplay</a>
+ <li><a class="subsection" href="#RootWindow">RootWindow / RootWindowOfScreen</a>
+ <li><a class="subsection" href="#DefaultRootWindow">DefaultRootWindow</a>
+ <li><a class="subsection" href="#DefaultVisual">DefaultVisual / DefaultVisualOfScreen</a>
+ <li><a class="subsection" href="#DefaultGC">DefaultGC / DefaultGCOfScreen</a>
+ <li><a class="subsection" href="#BlackPixel">BlackPixel / BlackPixelOfScreen</a>
+ <li><a class="subsection" href="#WhitePixel">WhitePixel / WhitePixelOfScreen</a>
+ <li><a class="subsection" href="#DisplayWidth">DisplayWidth / WidthOfScreen</a>
+ <li><a class="subsection" href="#DisplayHeight">DisplayHeight / HeightOfScreen</a>
+ <li><a class="subsection" href="#DisplayWidthMM">DisplayWidthMM / WidthMMOfScreen</a>
+ <li><a class="subsection" href="#DisplayHeightMM">DisplayHeightMM / HeightMMOfScreen</a>
+ <li><a class="subsection" href="#DisplayPlanes">DisplayPlanes / DefaultDepth / DefaultDepthOfScreen / PlanesOfScreen</a>
+ <li><a class="subsection" href="#DefaultColormap">DefaultColormap / DefaultColormapOfScreen</a>
+ <li><a class="subsection" href="#MinCmapsOfScreen">MinCmapsOfScreen</a>
+ <li><a class="subsection" href="#MaxCmapsOfScreen">MaxCmapsOfScreen</a>
+ <li><a class="subsection" href="#DoesSaveUnders">DoesSaveUnders</a>
+ <li><a class="subsection" href="#DoesBackingStore">DoesBackingStore</a>
+ <li><a class="subsection" href="#EventMaskOfScreen">EventMaskOfScreen</a>
+ </ol>
+ <li><a class="subsection" href="#misc">Miscellaneaous macros</a>
+ <ol>
+ <li><a class="subsection" href="#DisplayOfScreen">DisplayOfScreen</a>
+ <li><a class="subsection" href="#DisplayCells">DisplayCells / CellsOfScreen</a>
+ </ol>
+ </ol>
+ </ol>
+ </div>
+ <div class="section">
+ <ol>
+ <li class="title"><a name="intro">Introduction</a>
+ <p>
+ This tutorial is based on the
+ <a href="http://users.actcom.co.il/~choo/lupg/tutorials/xlib-programming/xlib-programming.html">Xlib Tutorial</a>
+ written by <a href="mailto:choor at atcom dot co dot il">Guy Keren</a>. The
+ author allowed me to take some parts of his text, mainly the text which
+ deals with the X Windows generality.
+ </p>
+ <p>
+ This tutorial is intended for people who want to start to program
+ with the <a href="http://xcb.freedesktop.org">XCB</a>
+ library. keep in mind that XCB, like the
+ <a href="http://tronche.com/gui/x/xlib/introduction">Xlib</a>
+ library, isn't what post programmers wanting to write X
+ applications are looking for. They should use a much higher
+ level GUI toolkit like Motif,
+ <a href="http://www.lesstif.org">LessTiff</a>,
+ <a href="http://www.gtk.org">GTK</a>,
+ <a href="http://www.trolltech.com">QT</a>,
+ <a href="http://www.enlightenment.org">EWL</a>,
+ <a href="http://www.enlightenment.org">ETK</a>, or use
+ <a href="http://cairographics.org">Cairo</a>.
+ However,
+ we need to start somewhere. More than this, knowing how things
+ work down below is never a bad idea.
+ </p>
+ <p>
+ After reading this tutorial, one should be able to write very
+ simple graphical programs, but not programs with decent user
+ interfaces. For such programs, one of the previously mentioned
+ libraries should be used.
+ </p>
+ <p>
+ But what is XCB? Xlib has been
+ the standard C binding for the <a href="http://www.x.org">X
+ Window System</a> protocol for many years now. It is an
+ excellent piece of work, but there are applications for which it
+ is not ideal, for example:
+ </p>
+ <ul>
+ <li><b>Small platforms</b>: Xlib is a large piece of code, and
+ it's difficult to make it smaller
+ <li><b>Latency hiding</b>: Xlib requests requiring a reply are
+ effectively synchronous: they block until the reply appears,
+ whether the result is needed immediately or not.
+ <li><b>Direct access to the protocol</b>: Xlib does quite a
+ bit of caching, layering, and similar optimizations. While this
+ is normally a feature, it makes it difficult to simply emit
+ specified X protocol requests and process specific
+ responses.
+ <li><b>Threaded applications</b>: While Xlib does attempt to
+ support multithreading, the API makes this difficult and
+ error-prone.
+ <li><b>New extensions</b>: The Xlib infrastructure provides
+ limited support for the new creation of X extension client side
+ code.
+ </ul>
+ <p>
+ For these reasons, among others, XCB, an X C binding, has been
+ designed to solve the above problems and thus provide a base for
+ </p>
+ <ul>
+ <li>Toolkit implementation.
+ <li>Direct protocol-level programming.
+ <li>Lightweight emulation of commonly used portions of the
+ Xlib API.
+ </ul>
+ <br>
+ <li class="title"><a name="Xmodel">The client and server model of the X window system</a>
+ <p>
+ The X Window System was developed with one major goal:
+ flexibility. The idea was that the way things look is one thing,
+ but the way things work is another matter. Thus, the lower
+ levels provide the tools required to draw windows, handle user
+ input, allow drawing graphics using colors (or black and white
+ screens), etc. To this point, a decision was made to separate
+ the system into two parts. A client that decides what to do, and
+ a server that actually draws on the screen and reads user input
+ in order to send it to the client for processing.
+ </p>
+ <p>
+ This model is the complete opposite of what is used to when
+ dealing with clients and servers. In our case, the user sits
+ near the machine controlled by the server, while the client
+ might be running on a remote machine. The server controls the
+ screens, mouse and keyboard. A client may connect to the server,
+ request that it draws a window (or several windows), and ask the
+ server to send it any input the user sends to these
+ windows. Thus, several clients may connect to a single X server
+ (one might be running mail software, one running a WWW
+ browser, etc). When input is sent by the user to some window,
+ the server sends a message to the client controlling this window
+ for processing. The client decides what to do with this input,
+ and sends the server requests for drawing in the window.
+ </p>
+ <p>
+ The whole session is carried out using the X message
+ protocol. This protocol was originally carried over the TCP/IP
+ protocol suite, allowing the client to run on any machine
+ connected to the same network that the server is. Later on, the
+ X servers were extended to allow clients running on the local
+ machine with more optimized access to the server (note that an X
+ protocol message may be several hundreds of KB in size), such as
+ using shared memory, or using Unix domain sockets (a method for
+ creating a logical channel on a Unix system between two processes).
+ </p>
+ <li class="title"><a name="asynch">GUI programming: the asynchronous model</a>
+ <p>
+ Unlike conventional computer programs, that carry some serial
+ nature, a GUI program usually uses an asynchronous programming
+ model, also known as "event-driven programming". This means that
+ that program mostly sits idle, waiting for events sent by the X
+ server, and then acts upon these events. An event may say "The
+ user pressed the 1st button mouse in spot (x,y)", or "The window
+ you control needs to be redrawn". In order for the program to be
+ responsive to the user input, as well as to refresh requests, it
+ needs to handle each event in a rather short period of time
+ (e.g. less that 200 milliseconds, as a rule of thumb).
+ </p>
+ <p>
+ This also implies that the program may not perform operations
+ that might take a long time while handling an event (such as
+ opening a network connection to some remote server, or
+ connecting to a database server, or even performing a long file
+ copy operation). Instead, it needs to perform all these
+ operations in an asynchronous manner. This may be done by using
+ various asynchronous models to perform the longish operations,
+ or by performing them in a different process or thread.
+ </p>
+ <p>
+ So the way a GUI program looks is something like that:
+ </p>
+ <ol>
+ <li>Perform initialization routines.
+ <li>Connect to the X server.
+ <li>Perform X-related initialization.
+ <li>While not finished:
+ <ol>
+ <li>Receive the next event from the X server.
+ <li>Handle the event, possibly sending various drawing
+ requests to the X server.
+ <li>If the event was a quit message, exit the loop.
+ </ol>
+ <li>Close down the connection to the X server.
+ <li>Perform cleanup operations.
+ </ol>
+ <br>
+ <li class="title"><a name="notions">Basic XCB notions</a>
+ <p>
+ XCB has been created to eliminate the need for
+ programs to actually implement the X protocol layer. This
+ library gives a program a very low-level access to any X
+ server. Since the protocol is standardized, a client using any
+ implementation of XCB may talk with any X server (the same
+ occurs for Xlib, of course). We now give a brief description of
+ the basic XCB notions. They will be detailed later.
+ </p>
+ <ol>
+ <li class="subtitle"><a name="conn">The X Connection</a>
+ <p>
+ The major notion of using XCB is the X Connection. This is a
+ structure representing the connection we have open with a
+ given X server. It hides a queue of messages coming from the
+ server, and a queue of pending requests that our client
+ intends to send to the server. In XCB, this structure is named
+ 'xcb_connection_t'. It is analogous to the Xlib Display.
+ When we open a connection to an X server, the
+ library returns a pointer to such a structure. Later, we
+ supply this pointer to any XCB function that should send
+ messages to the X server or receive messages from this server.
+ </p>
+ <li class="subtitle"><a name="requestsreplies">Requests and
+ replies: the Xlib killers</a>
+ <p>
+ To ask for information from the X server, we have to make a request
+ and ask for a reply. With Xlib, these two tasks are
+ automatically done: Xlib locks the system, sends a request,
+ waits for a reply from the X server and unlocks. This is
+ annoying, especially if one makes a lot of requests to the X
+ server. Indeed, Xlib has to wait for the end of a reply
+ before asking for the next request (because of the locks that
+ Xlib sends). For example, here is a time-line of N=4
+ requests/replies with Xlib, with a round-trip latency
+ <b>T_round_trip</b> that is 5 times long as the time required
+ to write or read a request/reply (<b>T_write/T_read</b>):
+ </p>
+ <pre class="text">
+ W-----RW-----RW-----RW-----R
+</pre>
+ <ul>
+ <li>W: Writing request
+ <li>-: Stalled, waiting for data
+ <li>R: Reading reply
+ </ul>
+ <p>
+ The total time is N * (T_write + T_round_trip + T_read).
+ </p>
+ <p>
+ With XCB, we can suppress most of the round-trips as the
+ requests and the replies are not locked. We usually send a
+ request, then XCB returns to us a <b>cookie</b>, which is an
+ identifier. Then, later, we ask for a reply using this
+ <b>cookie</b> and XCB returns a
+ pointer to that reply. Hence, with XCB, we can send a lot of
+ requests, and later in the program, ask for all the replies
+ when we need them. Here is the time-line for 4
+ requests/replies when we use this property of XCB:
+ </p>
+ <pre class="text">
+ WWWW--RRRR
+</pre>
+ <p>
+ The total time is N * T_write + max (0, T_round_trip - (N-1) *
+ T_write) + N * T_read. Which can be considerably faster than
+ all those Xlib round-trips.
+ </p>
+ <p>
+ Here is a program that computes the time to create 500 atoms
+ with Xlib and XCB. It shows the Xlib way, the bad XCB way
+ (which is similar to Xlib) and the good XCB way. On my
+ computer, XCB is 25 times faster than Xlib.
+ </p>
+ <pre class="code">
+#include &lt;stdlib.h&gt;
+#include &lt;stdio.h&gt;
+#include &lt;string.h&gt;
+#include &lt;sys/time.h&gt;
+
+#include &lt;xcb/xcb.h&gt;
+
+#include &lt;X11/Xlib.h&gt;
+
+double
+get_time(void)
+{
+ struct timeval timev;
+
+ gettimeofday(&amp;timev, NULL);
+
+ return (double)timev.tv_sec + (((double)timev.tv_usec) / 1000000);
+}
+
+int
+main ()
+{
+ xcb_connection_t *c;
+ xcb_atom_t *atoms;
+ xcb_intern_atom_cookie_t *cs;
+ char **names;
+ int count;
+ int i;
+ double start;
+ double end;
+ double diff;
+
+ /* Xlib */
+ Display *disp;
+ Atom *atoms_x;
+ double diff_x;
+
+ c = xcb_connect (NULL, NULL);
+
+ count = 500;
+ atoms = (xcb_atom_t *)malloc (count * sizeof (atoms));
+ names = (char **)malloc (count * sizeof (char *));
+
+ /* init names */
+ for (i = 0; i &lt; count; ++i) {
+ char buf[100];
+
+ sprintf (buf, "NAME%d", i);
+ names[i] = strdup (buf);
+ }
+
+ /* bad use */
+ start = get_time ();
+
+ for (i = 0; i &lt; count; ++i)
+ atoms[i] = xcb_intern_atom_reply (c,
+ xcb_intern_atom (c,
+ 0,
+ strlen(names[i]),
+ names[i]),
+ NULL)->atom;
+
+ end = get_time ();
+ diff = end - start;
+ printf ("bad use time : %f\n", diff);
+
+ /* good use */
+ start = get_time ();
+
+ cs = (xcb_intern_atom_cookie_t *) malloc (count * sizeof(xcb_intern_atom_cookie_t));
+ for(i = 0; i &lt; count; ++i)
+ cs[i] = xcb_intern_atom (c, 0, strlen(names[i]), names[i]);
+
+ for(i = 0; i &lt; count; ++i) {
+ xcb_intern_atom_reply_t *r;
+
+ r = xcb_intern_atom_reply(c, cs[i], 0);
+ if(r)
+ atoms[i] = r->atom;
+ free(r);
+ }
+
+ end = get_time ();
+ printf ("good use time : %f\n", end - start);
+ printf ("ratio : %f\n", diff / (end - start));
+ diff = end - start;
+
+ /* free var */
+ for (i = 0; i &lt; count; ++i)
+ free (names[i]);
+ free (atoms);
+ free (cs);
+
+ xcb_disconnect (c);
+
+ /* Xlib */
+ disp = XOpenDisplay (getenv("DISPLAY"));
+
+ atoms_x = (Atom *)malloc (count * sizeof (atoms_x));
+
+ start = get_time ();
+
+ for (i = 0; i &lt; count; ++i)
+ atoms_x[i] = XInternAtom(disp, names[i], 0);
+
+ end = get_time ();
+ diff_x = end - start;
+ printf ("Xlib use time : %f\n", diff_x);
+ printf ("ratio : %f\n", diff_x / diff);
+
+ free (atoms_x);
+ free (names);
+
+ XCloseDisplay (disp);
+
+ return 0;
+}
+</pre>
+ <li class="subtitle"><a name="gc">The Graphic Context</a>
+ <p>
+ When we perform various drawing operations (graphics, text,
+ etc), we may specify various options for controlling how the
+ data will be drawn (what foreground and background colors to
+ use, how line edges will be connected, what font to use when
+ drawing some text, etc). In order to avoid the need to supply
+ hundreds of parameters to each drawing function, a graphical
+ context structure is used. We set the various drawing options
+ in this structure, and then we pass a pointer to this
+ structure to any drawing routines. This is rather handy, as we
+ often need to perform several drawing requests with the same
+ options. Thus, we would initialize a graphical context, set
+ the desired options, and pass this structure to all drawing
+ functions.
+ </p>
+ <p>
+ Note that graphic contexts have no client-side structure in
+ XCB, they're just XIDs. Xlib has a client-side structure
+ because it caches the GC contents so it can avoid making
+ redundant requests, but of course XCB doesn't do that.
+ </p>
+ <li class="subtitle"><a name="events">Events</a>
+ <p>
+ A structure is used to pass events received from the X
+ server. XCB supports exactly the events specified in the
+ protocol (33 events). This structure contains the type
+ of event received (including a bit for whether it came
+ from the server or another client), as well as the data associated with the
+ event (e.g. position on the screen where the event was
+ generated, mouse button associated with the event, region of
+ the screen associated with a "redraw" event, etc). The way to
+ read the event's data depends on the event type.
+ </p>
+ </ol>
+ <br>
+ <li class="title"><a name="use">Using XCB-based programs</a>
+ <br>
+ <ol>
+ <li class="subtitle"><a name="inst">Installation of XCB</a>
+ <p>
+ <b>TODO:</b> These instructions are out of date.
+ Just reference the <a href="http://xcb.freedesktop.org/">main XCB page</a>
+ so we don't have to maintain these instructions in more than
+ one place.
+ </p>
+ <p>
+ To build XCB from source, you need to have installed at
+ least:
+ </p>
+ <ul>
+ <li>pkgconfig 0.15.0
+ <li><a href="http://www.gnu.org/software/automake/">automake 1.7</a>
+ <li><a href="http://www.gnu.org/software/autoconf/">autoconf 2.50</a>
+ <li><a href="http://www.check.org">check</a>
+ <li><a href="http://xmlsoft.org/XSLT/">xsltproc</a>
+ <li><a href="http://www.gnu.org/software/gperf/">gperf 3.0.1</a>
+ </ul>
+ <p>
+ You have to checkout in the git repository the following modules:
+ </p>
+ <ul>
+ <li>Xau from xlibs
+ <li>xcb-proto
+ <li>xcb
+ </ul>
+ <p>
+ Note that xcb-proto exists only to install header
+ files, so typing 'make' or 'make all' will produce the message
+ "Nothing to be done for 'all'". That's normal.
+ </p>
+ <li class="subtitle"><a name="comp">Compiling XCB-based programs</a>
+ <p>
+ Compiling XCB-based programs requires linking them with the XCB
+ library. This is easily done thanks to pkgconfig:
+ </p>
+ <pre class="text">
+gcc -Wall prog.c -o prog `pkg-config --cflags --libs xcb`
+</pre>
+ </ol>
+ <li class="title"><a name="openconn">Opening and closing the connection to an X server</a>
+ <p>
+ An X program first needs to open the connection to the X
+ server. There is a function that opens a connection. It requires
+ the display name, or NULL. In the latter case, the display name
+ will be the one in the environment variable DISPLAY.
+ </p>
+ <pre class="code">
+<span class="type">xcb_connection_t</span> *xcb_connect (<span class="keyword">const</span> <span class="type">char</span> *displayname,
+ <span class="type">int</span> *screenp);
+</pre>
+ <p>
+ The second parameter returns the screen number used for the
+ connection. The returned structure describes an XCB connection
+ and is opaque. Here is how the connection can be opened:
+ </p>
+ <pre class="code">
+#<span class="include">include</span> <span class="string">&lt;xcb/xcb.h&gt;</span>
+
+<span class="type">int</span>
+<span class="function">main</span> ()
+{
+ <span class="type">xcb_connection_t</span> *c;
+
+ /* Open the connection to the X server. Use the DISPLAY environment variable as the default display name */
+ c = xcb_connect (NULL, NULL);
+
+ <span class="keyword">return</span> 0;
+}
+</pre>
+ <p>
+ To close a connection, it suffices to use:
+ </p>
+ <pre class="code">
+<span class="type">void</span> xcb_disconnect (<span class="type">xcb_connection_t</span> *c);
+</pre>
+ <div class="comp">
+ <div class="title">
+ Comparison Xlib/XCB
+ </div>
+ <div class="xlib">
+ <ul>
+ <li>XOpenDisplay ()
+ </ul>
+ </div>
+ <div class="xcb">
+ <ul>
+ <li>xcb_connect ()
+ </ul>
+ </div>
+ <div class="xlib">
+ <ul>
+ <li>XCloseDisplay ()
+ </ul>
+ </div>
+ <div class="xcb">
+ <ul>
+ <li>xcb_disconnect ()
+ </ul>
+ </div>
+ </div>
+ <br>
+ <li class="title"><a name="screen">Checking basic information about a connection</a>
+ <p>
+ Once we have opened a connection to an X server, we should check some
+ basic information about it: what screens it has, what is the
+ size (width and height) of the screen, how many colors it
+ supports (black and white ? grey scale ?, 256 colors ? more ?),
+ and so on. We get such information from the xcb_screen_t
+ structure:
+ </p>
+ <pre class="code">
+typedef struct {
+ xcb_window_t root;
+ xcb_colormap_t default_colormap;
+ uint32_t white_pixel;
+ uint32_t black_pixel;
+ uint32_t current_input_masks;
+ uint16_t width_in_pixels;
+ uint16_t height_in_pixels;
+ uint16_t width_in_millimeters;
+ uint16_t height_in_millimeters;
+ uint16_t min_installed_maps;
+ uint16_t max_installed_maps;
+ xcb_visualid_t root_visual;
+ uint8_t backing_stores;
+ uint8_t save_unders;
+ uint8_t root_depth;
+ uint8_t allowed_depths_len;
+} xcb_screen_t;
+</pre>
+ <p>
+ We could retrieve the first screen of the connection by using the
+ following function:
+ </p>
+ <pre class="code">
+xcb_screen_iterator_t xcb_setup_roots_iterator (xcb_setup_t *R);
+</pre>
+ <p>
+ Here is a small program that shows how to use this function:
+ </p>
+ <pre class="code">
+#include &lt;stdio.h&gt;
+
+#include &lt;xcb/xcb.h&gt;
+
+int
+main ()
+{
+ xcb_connection_t *c;
+ xcb_screen_t *screen;
+ int screen_nbr;
+ xcb_screen_iterator_t iter;
+
+ /* Open the connection to the X server. Use the DISPLAY environment variable */
+ c = xcb_connect (NULL, &amp;screen_nbr);
+
+ /* Get the screen #screen_nbr */
+ iter = xcb_setup_roots_iterator (xcb_get_setup (c));
+ for (; iter.rem; --screen_nbr, xcb_screen_next (&amp;iter))
+ if (screen_nbr == 0) {
+ screen = iter.data;
+ break;
+ }
+
+ printf ("\n");
+ printf ("Informations of screen %ld:\n", screen-&gt;root);
+ printf (" width.........: %d\n", screen-&gt;width_in_pixels);
+ printf (" height........: %d\n", screen-&gt;height_in_pixels);
+ printf (" white pixel...: %ld\n", screen-&gt;white_pixel);
+ printf (" black pixel...: %ld\n", screen-&gt;black_pixel);
+ printf ("\n");
+
+ return 0;
+}
+</pre>
+ <li class="title"><a name="helloworld">Creating a basic window - the "hello world" program</a>
+ <p>
+ After we got some basic information about our screen, we can
+ create our first window. In the X Window System, a window is
+ characterized by an Id. So, in XCB, a window is of type:
+ </p>
+ <pre class="code">
+typedef uint32_t xcb_window_t;
+</pre>
+ <p>
+ We first ask for a new Id for our window, with this function:
+ </p>
+ <pre class="code">
+xcb_window_t xcb_generate_id(xcb_connection_t *c);
+</pre>
+ <p>
+ Then, XCB supplies the following function to create new windows:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_create_window (xcb_connection_t *c, /* Pointer to the xcb_connection_t structure */
+ uint8_t depth, /* Depth of the screen */
+ xcb_window_t wid, /* Id of the window */
+ xcb_window_t parent, /* Id of an existing window that should be the parent of the new window */
+ int16_t x, /* X position of the top-left corner of the window (in pixels) */
+ int16_t y, /* Y position of the top-left corner of the window (in pixels) */
+ uint16_t width, /* Width of the window (in pixels) */
+ uint16_t height, /* Height of the window (in pixels) */
+ uint16_t border_width, /* Width of the window's border (in pixels) */
+ uint16_t _class,
+ xcb_visualid_t visual,
+ uint32_t value_mask,
+ const uint32_t *value_list);
+</pre>
+ <p>
+ The fact that we created the window does not mean that it will
+ be drawn on screen. By default, newly created windows are not
+ mapped on the screen (they are invisible). In order to make our
+ window visible, we use the function <span class="code">xcb_map_window()</span>, whose
+ prototype is
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_map_window (xcb_connection_t *c,
+ xcb_window_t window);
+</pre>
+ <p>
+ Finally, here is a small program to create a window of size
+ 150x150 pixels, positioned at the top-left corner of the screen:
+ </p>
+ <pre class="code">
+#include &lt;unistd.h&gt; /* pause() */
+
+#include &lt;xcb/xcb.h&gt;
+
+int
+main ()
+{
+ xcb_connection_t *c;
+ xcb_screen_t *screen;
+ xcb_window_t win;
+
+ /* Open the connection to the X server */
+ c = xcb_connect (NULL, NULL);
+
+ /* Get the first screen */
+ screen = xcb_setup_roots_iterator (xcb_get_setup (c)).data;
+
+ /* Ask for our window's Id */
+ win = xcb_generate_id(c);
+
+ /* Create the window */
+ xcb_create_window (c, /* Connection */
+ XCB_COPY_FROM_PARENT, /* depth (same as root)*/
+ win, /* window Id */
+ screen-&gt;root, /* parent window */
+ 0, 0, /* x, y */
+ 150, 150, /* width, height */
+ 10, /* border_width */
+ XCB_WINDOW_CLASS_INPUT_OUTPUT, /* class */
+ screen-&gt;root_visual, /* visual */
+ 0, NULL); /* masks, not used yet */
+
+ /* Map the window on the screen */
+ xcb_map_window (c, win);
+
+ /* Make sure commands are sent before we pause, so window is shown */
+ xcb_flush (c);
+
+ pause (); /* hold client until Ctrl-C */
+
+ return 0;
+}
+</pre>
+ <p>
+ In this code, you see one more function - <span class="code">xcb_flush()</span>, not explained
+ yet. It is used to flush all the pending requests. More
+ precisely, there are 2 functions that do such things. The first
+ one is <span class="code">xcb_flush()</span>:
+ </p>
+ <pre class="code">
+int xcb_flush (xcb_connection_t *c);
+</pre>
+ <p>
+ This function flushes all pending requests to the X server (much
+ like the <span class="code">fflush()</span> function is used to
+ flush standard output). The second function is
+ <span class="code">xcb_aux_sync()</span>:
+ </p>
+ <pre class="code">
+int xcb_aux_sync (xcb_connection_t *c);
+</pre>
+ <p>
+ This functions also flushes all pending requests to the X
+ server, and then waits until the X server finishing processing
+ these requests. In a normal program, this will not be necessary
+ (we'll see why when we get to write a normal X program), but for
+ now, we put it there.
+ </p>
+ <p>
+ The window that is created by the above code has a non defined
+ background. This one can be set to a specific color,
+ thanks to the two last parameters of
+ <span class="code">xcb_create_window()</span>, which are not
+ described yet. See the subsections
+ <a href="#winconf">Configuring a window</a> or
+ <a href="#winconf">Registering for event types using event masks</a>
+ for examples on how to use these parameters. In addition, as no
+ events are handled, you have to make a Ctrl-C to interrupt the
+ program.
+ </p>
+ <p>
+ <b>TODO</b>: one should tell what these functions return and
+ about the generic error
+ </p>
+ <div class="comp">
+ <div class="title">
+ Comparison Xlib/XCB
+ </div>
+ <div class="xlib">
+ <ul>
+ <li>XCreateWindow ()
+ </ul>
+ </div>
+ <div class="xcb">
+ <ul>
+ <li>xcb_generate_id ()
+ <li>xcb_create_window ()
+ </ul>
+ </div>
+ </div>
+ <br>
+ <li class="title"><a name="drawing">Drawing in a window</a>
+ <p>
+ Drawing in a window can be done using various graphical
+ functions (drawing pixels, lines, rectangles, etc). In order to
+ draw in a window, we first need to define various general
+ drawing parameters (what line width to use, which color to draw
+ with, etc). This is done using a graphical context.
+ </p>
+ <ol>
+ <li class="subtitle"><a name="allocgc">Allocating a Graphics Context</a>
+ <p>
+ As we said, a graphical context defines several attributes to
+ be used with the various drawing functions. For this, we
+ define a graphical context. We can use more than one graphical
+ context with a single window, in order to draw in multiple
+ styles (different colors, different line widths, etc). In XCB,
+ a Graphics Context is, as a window, characterized by an Id:
+ </p>
+ <pre class="code">
+typedef uint32_t xcb_gcontext_t;
+</pre>
+ <p>
+ We first ask the X server to attribute an Id to our graphic
+ context with this function:
+ </p>
+ <pre class="code">
+xcb_gcontext_t xcb_generate_id (xcb_connection_t *c);
+</pre>
+ <p>
+ Then, we set the attributes of the graphic context with this function:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_create_gc (xcb_connection_t *c,
+ xcb_gcontext_t cid,
+ xcb_drawable_t drawable,
+ uint32_t value_mask,
+ const uint32_t *value_list);
+</pre>
+ <p>
+ We give now an example on how to allocate a graphic context
+ that specifies that each drawing function that uses it will
+ draw in foreground with a black color.
+ </p>
+ <pre class="code">
+#include &lt;xcb/xcb.h&gt;
+
+int
+main ()
+{
+ xcb_connection_t *c;
+ xcb_screen_t *screen;
+ xcb_drawable_t win;
+ xcb_gcontext_t black;
+ uint32_t mask;
+ uint32_t value[1];
+
+ /* Open the connection to the X server and get the first screen */
+ c = xcb_connect (NULL, NULL);
+ screen = xcb_setup_roots_iterator (xcb_get_setup (c)).data;
+
+ /* Create a black graphic context for drawing in the foreground */
+ win = screen-&gt;root;
+ black = xcb_generate_id (c);
+ mask = XCB_GC_FOREGROUND;
+ value[0] = screen-&gt;black_pixel;
+ xcb_create_gc (c, black, win, mask, value);
+
+ return 0;
+}
+</pre>
+ <p>
+ Note should be taken regarding the role of "value_mask" and
+ "value_list" in the prototype of <span class="code">xcb_create_gc()</span>. Since a
+ graphic context has many attributes, and since we often just
+ want to define a few of them, we need to be able to tell the
+ <span class="code">xcb_create_gc()</span> which attributes we
+ want to set. This is what the "value_mask" parameter is
+ for. We then use the "value_list" parameter to specify actual
+ values for the attribute we defined in "value_mask". Thus, for
+ each constant used in "value_list", we will use the matching
+ constant in "value_mask". In this case, we define a graphic
+ context with one attribute: when drawing (a point, a line,
+ etc), the foreground color will be black. The rest of the
+ attributes of this graphic context will be set to their
+ default values.
+ </p>
+ <p>
+ See the next Subsection for more details.
+ </p>
+ <div class="comp">
+ <div class="title">
+ Comparison Xlib/XCB
+ </div>
+ <div class="xlib">
+ <ul>
+ <li>XCreateGC ()
+ </ul>
+ </div>
+ <div class="xcb">
+ <ul>
+ <li>xcb_generate_id ()
+ <li>xcb_create_gc ()
+ </ul>
+ </div>
+ </div>
+ <br>
+ <li class="subtitle"><a name="changegc">Changing the attributes of a Graphics Context</a>
+ <p>
+ Once we have allocated a Graphic Context, we may need to
+ change its attributes (for example, changing the foreground
+ color we use to draw a line, or changing the attributes of the
+ font we use to display strings. See Subsections Drawing with a
+ color and
+ <a href="#assigningfont">Assigning a Font to a Graphic Context</a>).
+ This is done by using this function:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_change_gc (xcb_connection_t *c, /* The XCB Connection */
+ xcb_gcontext_t gc, /* The Graphic Context */
+ uint32_t value_mask, /* Components of the Graphic Context that have to be set */
+ const uint32_t *value_list); /* Value as specified by value_mask */
+</pre>
+ <p>
+ The <span class="code">value_mask</span> parameter could take
+ any combination of these masks from the xcb_gc_t enumeration:
+ </p>
+ <ul>
+ <li>XCB_GC_FUNCTION
+ <li>XCB_GC_PLANE_MASK
+ <li>XCB_GC_FOREGROUND
+ <li>XCB_GC_BACKGROUND
+ <li>XCB_GC_LINE_WIDTH
+ <li>XCB_GC_LINE_STYLE
+ <li>XCB_GC_CAP_STYLE
+ <li>XCB_GC_JOIN_STYLE
+ <li>XCB_GC_FILL_STYLE
+ <li>XCB_GC_FILL_RULE
+ <li>XCB_GC_TILE
+ <li>XCB_GC_STIPPLE
+ <li>XCB_GC_TILE_STIPPLE_ORIGIN_X
+ <li>XCB_GC_TILE_STIPPLE_ORIGIN_Y
+ <li>XCB_GC_FONT
+ <li>XCB_GC_SUBWINDOW_MODE
+ <li>XCB_GC_GRAPHICS_EXPOSURES
+ <li>XCB_GC_CLIP_ORIGIN_X
+ <li>XCB_GC_CLIP_ORIGIN_Y
+ <li>XCB_GC_CLIP_MASK
+ <li>XCB_GC_DASH_OFFSET
+ <li>XCB_GC_DASH_LIST
+ <li>XCB_GC_ARC_MODE
+ </ul>
+ <p>
+ It is possible to set several attributes at the same
+ time (for example setting the attributes of a font and the
+ color which will be used to display a string), by OR'ing these
+ values in <span class="code">value_mask</span>. Then
+ <span class="code">value_list</span> has to be an array which
+ lists the value for the respective attributes. <b>These values
+ must be in the same order as masks listed above.</b> See Subsection
+ Drawing with a color to have an example.
+ </p>
+ <p>
+ <b>TODO</b>: set the links of the 3 subsections, once they will
+ be written :)
+ </p>
+ <p>
+ <b>TODO</b>: give an example which sets several attributes.
+ </p>
+ <li class="subtitle"><a name="drawingprim">Drawing primitives: point, line, box, circle,...</a>
+ <p>
+ After we have created a Graphic Context, we can draw on a
+ window using this Graphic Context, with a set of XCB
+ functions, collectively called "drawing primitives". Let see
+ how they are used.
+ </p>
+ <p>
+ To draw a point, or several points, we use
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_poly_point (xcb_connection_t *c, /* The connection to the X server */
+ uint8_t coordinate_mode, /* Coordinate mode, usually set to XCB_COORD_MODE_ORIGIN */
+ xcb_drawable_t drawable, /* The drawable on which we want to draw the point(s) */
+ xcb_gcontext_t gc, /* The Graphic Context we use to draw the point(s) */
+ uint32_t points_len, /* The number of points */
+ const xcb_point_t *points); /* An array of points */
+</pre>
+ <p>
+ The <span class="code">coordinate_mode</span> parameter
+ specifies the coordinate mode. Available values are
+ </p>
+ <ul>
+ <li><span class="code">XCB_COORD_MODE_ORIGIN</span>
+ <li><span class="code">XCB_COORD_MODE_PREVIOUS</span>
+ </ul>
+ <p>
+ If XCB_COORD_MODE_PREVIOUS is used, then all points but the first one
+ are relative to the immediately previous point.
+ </p>
+ <p>
+ The <span class="code">xcb_point_t</span> type is just a
+ structure with two fields (the coordinates of the point):
+ </p>
+ <pre class="code">
+typedef struct {
+ int16_t x;
+ int16_t y;
+} xcb_point_t;
+</pre>
+ <p>
+ You could see an example in xpoints.c. <b>TODO</b> Set the link.
+ </p>
+ <p>
+ To draw a line, or a polygonal line, we use
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_poly_line (xcb_connection_t *c, /* The connection to the X server */
+ uint8_t coordinate_mode, /* Coordinate mode, usually set to XCB_COORD_MODE_ORIGIN */
+ xcb_drawable_t drawable, /* The drawable on which we want to draw the line(s) */
+ xcb_gcontext_t gc, /* The Graphic Context we use to draw the line(s) */
+ uint32_t points_len, /* The number of points in the polygonal line */
+ const xcb_point_t *points); /* An array of points */
+</pre>
+ <p>
+ This function will draw the line between the first and the
+ second points, then the line between the second and the third
+ points, and so on.
+ </p>
+ <p>
+ To draw a segment, or several segments, we use
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_poly_segment (xcb_connection_t *c, /* The connection to the X server */
+ xcb_drawable_t drawable, /* The drawable on which we want to draw the segment(s) */
+ xcb_gcontext_t gc, /* The Graphic Context we use to draw the segment(s) */
+ uint32_t segments_len, /* The number of segments */
+ const xcb_segment_t *segments); /* An array of segments */
+</pre>
+ <p>
+ The <span class="code">xcb_segment_t</span> type is just a
+ structure with four fields (the coordinates of the two points
+ that define the segment):
+ </p>
+ <pre class="code">
+typedef struct {
+ int16_t x1;
+ int16_t y1;
+ int16_t x2;
+ int16_t y2;
+} xcb_segment_t;
+</pre>
+ <p>
+ To draw a rectangle, or several rectangles, we use
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_poly_rectangle (xcb_connection_t *c, /* The connection to the X server */
+ xcb_drawable_t drawable, /* The drawable on which we want to draw the rectangle(s) */
+ xcb_gcontext_t gc, /* The Graphic Context we use to draw the rectangle(s) */
+ uint32_t rectangles_len, /* The number of rectangles */
+ const xcb_rectangle_t *rectangles); /* An array of rectangles */
+</pre>
+ <p>
+ The <span class="code">xcb_rectangle_t</span> type is just a
+ structure with four fields (the coordinates of the top-left
+ corner of the rectangle, and its width and height):
+ </p>
+ <pre class="code">
+typedef struct {
+ int16_t x;
+ int16_t y;
+ uint16_t width;
+ uint16_t height;
+} xcb_rectangle_t;
+</pre>
+ <!-- There's no coordinate_mode. Is it normal? -->
+ <!-- [iano] Yes, it's not in the protocol. -->
+ <p>
+ To draw an elliptical arc, or several elliptical arcs, we use
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_poly_arc (xcb_connection_t *c, /* The connection to the X server */
+ xcb_drawable_t drawable, /* The drawable on which we want to draw the arc(s) */
+ xcb_gcontext_t gc, /* The Graphic Context we use to draw the arc(s) */
+ uint32_t arcs_len, /* The number of arcs */
+ const xcb_arc_t *arcs); /* An array of arcs */
+</pre>
+ <p>
+ The <span class="code">xcb_arc_t</span> type is a structure with
+ six fields:
+ </p>
+ <pre class="code">
+typedef struct {
+ int16_t x; /* Top left x coordinate of the rectangle surrounding the ellipse */
+ int16_t y; /* Top left y coordinate of the rectangle surrounding the ellipse */
+ uint16_t width; /* Width of the rectangle surrounding the ellipse */
+ uint16_t height; /* Height of the rectangle surrounding the ellipse */
+ int16_t angle1; /* Angle at which the arc begins */
+ int16_t angle2; /* Angle at which the arc ends */
+} xcb_arc_t;
+</pre>
+ <div class="emph">
+ <p>
+ Note: the angles are expressed in units of 1/64 of a degree,
+ so to have an angle of 90 degrees, starting at 0,
+ <span class="code">angle1 = 0</span> and
+ <span class="code">angle2 = 90 &lt;&lt; 6</span>. Positive angles
+ indicate counterclockwise motion, while negative angles
+ indicate clockwise motion.
+ </p>
+ </div>
+ <!-- I think that (x,y) should be the center of the
+ ellipse, and (width, height) the radius. It's more logical. -->
+ <!-- iano: Yes, and I bet some toolkits do that.
+ But the protocol (and many other graphics APIs) define arcs
+ by bounding rectangles. -->
+ <p>
+ The corresponding function which fill inside the geometrical
+ object are listed below, without further explanation, as they
+ are used as the above functions.
+ </p>
+ <p>
+ To Fill a polygon defined by the points given as arguments ,
+ we use
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_fill_poly (xcb_connection_t *c,
+ xcb_drawable_t drawable,
+ xcb_gcontext_t gc,
+ uint8_t shape,
+ uint8_t coordinate_mode,
+ uint32_t points_len,
+ const xcb_point_t *points);
+</pre>
+ <p>
+ The <span class="code">shape</span> parameter specifies a
+ shape that helps the server to improve performance. Available
+ values are
+ </p>
+ <ul>
+ <li><span class="code">XCB_POLY_SHAPE_COMPLEX</span>
+ <li><span class="code">XCB_POLY_SHAPE_NONCONVEX</span>
+ <li><span class="code">XCB_POLY_SHAPE_CONVEX</span>
+ </ul>
+ <p>
+ To fill one or several rectangles, we use
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_poly_fill_rectangle (xcb_connection_t *c,
+ xcb_drawable_t drawable,
+ xcb_gcontext_t gc,
+ uint32_t rectangles_len,
+ const xcb_rectangle_t *rectangles);
+</pre>
+ <p>
+ To fill one or several arcs, we use
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_poly_fill_arc (xcb_connection_t *c,
+ xcb_drawable_t drawable,
+ xcb_gcontext_t gc,
+ uint32_t arcs_len,
+ const xcb_arc_t *arcs);
+</pre>
+ <br>
+ <a name="points.c"></a>
+ <p>
+ To illustrate these functions, here is an example that draws
+ four points, a polygonal line, two segments, two rectangles
+ and two arcs. Remark that we use events for the first time, as
+ an introduction to the next section.
+ </p>
+ <p>
+ <b>TODO:</b> Use screen-&gt;root_depth for depth parameter.
+ </p>
+ <pre class="code">
+#include &lt;stdlib.h&gt;
+#include &lt;stdio.h&gt;
+
+#include &lt;xcb/xcb.h&gt;
+
+int
+main ()
+{
+ xcb_connection_t *c;
+ xcb_screen_t *screen;
+ xcb_drawable_t win;
+ xcb_gcontext_t foreground;
+ xcb_generic_event_t *e;
+ uint32_t mask = 0;
+ uint32_t values[2];
+
+ /* geometric objects */
+ xcb_point_t points[] = {
+ {10, 10},
+ {10, 20},
+ {20, 10},
+ {20, 20}};
+
+ xcb_point_t polyline[] = {
+ {50, 10},
+ { 5, 20}, /* rest of points are relative */
+ {25,-20},
+ {10, 10}};
+
+ xcb_segment_t segments[] = {
+ {100, 10, 140, 30},
+ {110, 25, 130, 60}};
+
+ xcb_rectangle_t rectangles[] = {
+ { 10, 50, 40, 20},
+ { 80, 50, 10, 40}};
+
+ xcb_arc_t arcs[] = {
+ {10, 100, 60, 40, 0, 90 &lt;&lt; 6},
+ {90, 100, 55, 40, 0, 270 &lt;&lt; 6}};
+
+ /* Open the connection to the X server */
+ c = xcb_connect (NULL, NULL);
+
+ /* Get the first screen */
+ screen = xcb_setup_roots_iterator (xcb_get_setup (c)).data;
+
+ /* Create black (foreground) graphic context */
+ win = screen-&gt;root;
+
+ foreground = xcb_generate_id (c);
+ mask = XCB_GC_FOREGROUND | XCB_GC_GRAPHICS_EXPOSURES;
+ values[0] = screen-&gt;black_pixel;
+ values[1] = 0;
+ xcb_create_gc (c, foreground, win, mask, values);
+
+ /* Ask for our window's Id */
+ win = xcb_generate_id(c);
+
+ /* Create the window */
+ mask = XCB_CW_BACK_PIXEL | XCB_CW_EVENT_MASK;
+ values[0] = screen-&gt;white_pixel;
+ values[1] = XCB_EVENT_MASK_EXPOSURE;
+ xcb_create_window (c, /* Connection */
+ XCB_COPY_FROM_PARENT, /* depth */
+ win, /* window Id */
+ screen-&gt;root, /* parent window */
+ 0, 0, /* x, y */
+ 150, 150, /* width, height */
+ 10, /* border_width */
+ XCB_WINDOW_CLASS_INPUT_OUTPUT, /* class */
+ screen-&gt;root_visual, /* visual */
+ mask, values); /* masks */
+
+ /* Map the window on the screen */
+ xcb_map_window (c, win);
+
+
+ /* We flush the request */
+ xcb_flush (c);
+
+ while ((e = xcb_wait_for_event (c))) {
+ switch (e-&gt;response_type &amp; ~0x80) {
+ case XCB_EXPOSE: {
+ /* We draw the points */
+ xcb_poly_point (c, XCB_COORD_MODE_ORIGIN, win, foreground, 4, points);
+
+ /* We draw the polygonal line */
+ xcb_poly_line (c, XCB_COORD_MODE_PREVIOUS, win, foreground, 4, polyline);
+
+ /* We draw the segements */
+ xcb_poly_segment (c, win, foreground, 2, segments);
+
+ /* We draw the rectangles */
+ xcb_poly_rectangle (c, win, foreground, 2, rectangles);
+
+ /* We draw the arcs */
+ xcb_poly_arc (c, win, foreground, 2, arcs);
+
+ /* We flush the request */
+ xcb_flush (c);
+
+ break;
+ }
+ default: {
+ /* Unknown event type, ignore it */
+ break;
+ }
+ }
+ /* Free the Generic Event */
+ free (e);
+ }
+
+ return 0;
+}
+</pre>
+ </ol>
+ <li class="title"><a name="xevents">X Events</a>
+ <p>
+ In an X program, everything is driven by events. Event painting
+ on the screen is sometimes done as a response to an event (an
+ <span class="code">Expose</span> event). If part of a program's
+ window that was hidden, gets exposed (e.g. the window was raised
+ above other widows), the X server will send an "expose" event to
+ let the program know it should repaint that part of the
+ window. User input (key presses, mouse movement, etc) is also
+ received as a set of events.
+ </p>
+ <ol>
+ <li class="subtitle"><a name="register">Registering for event types using event masks</a>
+ <p>
+ During the creation of a window, you should give it what kind
+ of events it wishes to receive. Thus, you may register for
+ various mouse (also called pointer) events, keyboard events,
+ expose events, and so on. This is done for optimizing the
+ server-to-client connection (i.e. why send a program (that
+ might even be running at the other side of the globe) an event
+ it is not interested in ?)
+ </p>
+ <p>
+ In XCB, you use the "value_mask" and "value_list" data in the
+ <span class="code">xcb_create_window()</span> function to
+ register for events. Here is how we register for
+ <span class="code">Expose</span> event when creating a window:
+ </p>
+ <pre class="code">
+ mask = XCB_CW_EVENT_MASK;
+ valwin[0] = XCB_EVENT_MASK_EXPOSURE;
+ win = xcb_generate_id (c);
+ xcb_create_window (c, depth, win, root-&gt;root,
+ 0, 0, 150, 150, 10,
+ XCB_WINDOW_CLASS_INPUT_OUTPUT, root-&gt;root_visual,
+ mask, valwin);
+</pre>
+ <p>
+ <span class="code">XCB_EVENT_MASK_EXPOSURE</span> is a constant defined
+ in the xcb_event_mask_t enumeration in the "xproto.h" header file. If we wanted to register for several
+ event types, we can logically "or" them, as follows:
+ </p>
+ <pre class="code">
+ mask = XCB_CW_EVENT_MASK;
+ valwin[0] = XCB_EVENT_MASK_EXPOSURE | XCB_EVENT_MASK_BUTTON_PRESS;
+ win = xcb_generate_id (c);
+ xcb_create_window (c, depth, win, root-&gt;root,
+ 0, 0, 150, 150, 10,
+ XCB_WINDOW_CLASS_INPUT_OUTPUT, root-&gt;root_visual,
+ mask, valwin);
+</pre>
+ <p>
+ This registers for <span class="code">Expose</span> events as
+ well as for mouse button presses inside the created
+ window. You should note that a mask may represent several
+ event sub-types.
+ </p>
+ <p>
+ The values that a mask could take are given
+ by the <span class="code">xcb_cw_t</span> enumeration:
+ </p>
+ <pre class="code">
+typedef enum {
+ XCB_CW_BACK_PIXMAP = 1L<<0,
+ XCB_CW_BACK_PIXEL = 1L<<1,
+ XCB_CW_BORDER_PIXMAP = 1L<<2,
+ XCB_CW_BORDER_PIXEL = 1L<<3,
+ XCB_CW_BIT_GRAVITY = 1L<<4,
+ XCB_CW_WIN_GRAVITY = 1L<<5,
+ XCB_CW_BACKING_STORE = 1L<<6,
+ XCB_CW_BACKING_PLANES = 1L<<7,
+ XCB_CW_BACKING_PIXEL = 1L<<8,
+ XCB_CW_OVERRIDE_REDIRECT = 1L<<9,
+ XCB_CW_SAVE_UNDER = 1L<<10,
+ XCB_CW_EVENT_MASK = 1L<<11,
+ XCB_CW_DONT_PROPAGATE = 1L<<12,
+ XCB_CW_COLORMAP = 1L<<13,
+ XCB_CW_CURSOR = 1L<<14
+} xcb_cw_t;
+</pre>
+ <div class="emph">
+ <p>Note: we must be careful when setting the values of the valwin
+ parameter, as they have to follow the order the
+ <span class="code">xcb_cw_t</span> enumeration. Here is an
+ example:
+ </p>
+ </div>
+ <pre class="code">
+ mask = XCB_CW_EVENT_MASK | XCB_CW_BACK_PIXMAP;
+ valwin[0] = XCB_NONE; /* for XCB_CW_BACK_PIXMAP (whose value is 1) */
+ valwin[1] = XCB_EVENT_MASK_EXPOSURE | XCB_EVENT_MASK_BUTTON_PRESS; /* for XCB_CW_EVENT_MASK, whose value (2048) */
+ /* is greater than the one of XCB_CW_BACK_PIXMAP */
+</pre>
+ <p>
+ If the window has already been created, we can use the
+ <span class="code">xcb_configure_window()</span> function to set
+ the events that the window will receive. The subsection
+ <a href="#winconf">Configuring a window</a> shows its
+ prototype. As an example, here is a piece of code that
+ configures the window to receive the
+ <span class="code">Expose</span> and
+ <span class="code">ButtonPress</span> events:
+ </p>
+ <pre class="code">
+const static uint32_t values[] = { XCB_EVENT_MASK_EXPOSURE | XCB_EVENT_MASK_BUTTON_PRESS };
+
+/* The connection c and the window win are supposed to be defined */
+
+xcb_configure_window (c, win, XCB_CW_EVENT_MASK, values);
+</pre>
+ <div class="emph">
+ <p>
+ Note: A common bug programmers do is adding code to handle new
+ event types in their program, while forgetting to add the
+ masks for these events in the creation of the window. Such a
+ programmer then should sit down for hours debugging his
+ program, wondering "Why doesn't my program notice that I
+ released the button?", only to find that they registered for
+ button press events but not for button release events.
+ </p>
+ </div>
+ <li class="subtitle"><a name="loop">Receiving events: writing the events loop</a>
+ <p>
+ After we have registered for the event types we are interested
+ in, we need to enter a loop of receiving events and handling
+ them. There are two ways to receive events: a blocking way and
+ a non-blocking way:
+ </p>
+ <ul>
+ <li>
+ <span class="code">xcb_wait_for_event (xcb_connection_t *c)</span>
+ is the blocking way. It waits (so blocks...) until an event is
+ queued in the X server. Then it retrieves it into a newly
+ allocated structure (it dequeues it from the queue) and returns
+ it. This structure has to be freed. The function returns
+ <span class="code">NULL</span> if an error occurs.
+
+ <br>
+ <li>
+ <span class="code">xcb_poll_for_event (xcb_connection_t *c, int
+ *error)</span> is the non-blocking way. It looks at the event
+ queue and returns (and dequeues too) an existing event into
+ a newly allocated structure. This structure has to be
+ freed. It returns <span class="code">NULL</span> if there is
+ no event. If an error occurs, the parameter <span
+ class="code">error</span> will be filled with the error
+ status.
+ </ul>
+ <p>
+ There are various ways to write such a loop. We present two
+ ways to write such a loop, with the two functions above. The
+ first one uses <span class="code">xcb_wait_for_event_t</span>, which
+ is similar to an event Xlib loop using only <span
+ class="code">XNextEvent</span>:
+ </p>
+ <pre class="code">
+ xcb_generic_event_t *e;
+
+ while ((e = xcb_wait_for_event (c))) {
+ switch (e-&gt;response_type &amp; ~0x80) {
+ case XCB_EXPOSE: {
+ /* Handle the Expose event type */
+ xcb_expose_event_t *ev = (xcb_expose_event_t *)e;
+
+ /* ... */
+
+ break;
+ }
+ case XCB_BUTTON_PRESS: {
+ /* Handle the ButtonPress event type */
+ xcb_button_press_event_t *ev = (xcb_button_press_event_t *)e;
+
+ /* ... */
+
+ break;
+ }
+ default: {
+ /* Unknown event type, ignore it */
+ break;
+ }
+ }
+ /* Free the Generic Event */
+ free (e);
+ }
+</pre>
+ <p>
+ You will certainly want to use <span
+ class="code">xcb_poll_for_event(xcb_connection_t *c, int
+ *error)</span> if, in Xlib, you use <span
+ class="code">XPending</span> or
+ <span class="code">XCheckMaskEvent</span>:
+ </p>
+ <pre class="code">
+ while (XPending (display)) {
+ XEvent ev;
+
+ XNextEvent(d, &amp;ev);
+
+ /* Manage your event */
+ }
+</pre>
+ <p>
+ Such a loop in XCB looks like:
+ </p>
+ <pre class="code">
+ xcb_generic_event_t *ev;
+
+ while ((ev = xcb_poll_for_event (conn, 0))) {
+ /* Manage your event */
+ }
+</pre>
+ <p>
+ The events are managed in the same way as with <span
+ class="code">xcb_wait_for_event_t</span>.
+ Obviously, we will need to give the user some way of
+ terminating the program. This is usually done by handling a
+ special "quit" event, as we will soon see.
+ </p>
+ <div class="comp">
+ <div class="title">
+ Comparison Xlib/XCB
+ </div>
+ <div class="xlib">
+ <ul>
+ <li>XNextEvent ()
+ </ul>
+ </div>
+ <div class="xcb">
+ <ul>
+ <li>xcb_wait_for_event ()
+ </ul>
+ </div>
+ <div class="xlib">
+ <ul>
+ <li>XPending ()
+ <li>XCheckMaskEvent ()
+ </ul>
+ </div>
+ <div class="xcb">
+ <ul>
+ <li>xcb_poll_for_event ()
+ </ul>
+ </div>
+ </div>
+ <br>
+ <li class="subtitle"><a name="expose">Expose events</a>
+ <p>
+ The <span class="code">Expose</span> event is one of the most
+ basic (and most used) events an application may receive. It
+ will be sent to us in one of several cases:
+ </p>
+ <ul>
+ <li>A window that covered part of our window has moved
+ away, exposing part (or all) of our window.
+ <li>Our window was raised above other windows.
+ <li>Our window mapped for the first time.
+ <li>Our window was de-iconified.
+ </ul>
+ <p>
+ You should note the implicit assumption hidden here: the
+ contents of our window is lost when it is being obscured
+ (covered) by either windows. One may wonder why the X server
+ does not save this contents. The answer is: to save
+ memory. After all, the number of windows on a display at a
+ given time may be very large, and storing the contents of all
+ of them might require a lot of memory. Actually, there is a
+ way to tell the X server to store the contents of a window in
+ special cases, as we will see later.
+ </p>
+ <p>
+ When we get an <span class="code">Expose</span> event, we
+ should take the event's data from the members of the following
+ structure:
+ </p>
+ <pre class="code">
+typedef struct {
+ uint8_t response_type; /* The type of the event, here it is XCB_EXPOSE */
+ uint8_t pad0;
+ uint16_t sequence;
+ xcb_window_t window; /* The Id of the window that receives the event (in case */
+ /* our application registered for events on several windows */
+ uint16_t x; /* The x coordinate of the top-left part of the window that needs to be redrawn */
+ uint16_t y; /* The y coordinate of the top-left part of the window that needs to be redrawn */
+ uint16_t width; /* The width of the part of the window that needs to be redrawn */
+ uint16_t height; /* The height of the part of the window that needs to be redrawn */
+ uint16_t count;
+} xcb_expose_event_t;
+</pre>
+ <li class="subtitle"><a name="userinput">Getting user input</a>
+ <p>
+ User input traditionally comes from two sources: the mouse
+ and the keyboard. Various event types exist to notify us of
+ user input (a key being presses on the keyboard, a key being
+ released on the keyboard, the mouse moving over our window,
+ the mouse entering (or leaving) our window, and so on.
+ </p>
+ <ol>
+ <li class="subsubtitle"><a name="mousepressrelease">Mouse button press and release events</a>
+ <p>
+ The first event type we will deal with is a mouse
+ button-press (or button-release) event in our window. In
+ order to register to such an event type, we should add one
+ (or more) of the following masks when we create our window:
+ </p>
+ <ul>
+ <li><span class="code">XCB_EVENT_MASK_BUTTON_PRESS</span>: notify us
+ of any button that was pressed in one of our windows.
+ <li><span class="code">XCB_EVENT_MASK_BUTTON_RELEASE</span>: notify us
+ of any button that was released in one of our windows.
+ </ul>
+ <p>
+ The structure to be checked for in our events loop is the
+ same for these two events, and is the following:
+ </p>
+ <pre class="code">
+typedef struct {
+ uint8_t response_type; /* The type of the event, here it is xcb_button_press_event_t or xcb_button_release_event_t */
+ xcb_button_t detail;
+ uint16_t sequence;
+ xcb_timestamp_t time; /* Time, in milliseconds the event took place in */
+ xcb_window_t root;
+ xcb_window_t event;
+ xcb_window_t child;
+ int16_t root_x;
+ int16_t root_y;
+ int16_t event_x; /* The x coordinate where the mouse has been pressed in the window */
+ int16_t event_y; /* The y coordinate where the mouse has been pressed in the window */
+ uint16_t state; /* A mask of the buttons (or keys) during the event */
+ uint8_t same_screen;
+} xcb_button_press_event_t;
+
+typedef xcb_button_press_event_t xcb_button_release_event_t;
+</pre>
+ <p>
+ The <span class="code">time</span> field may be used to calculate "double-click"
+ situations by an application (e.g. if the mouse button was
+ clicked two times in a duration shorter than a given amount
+ of time, assume this was a double click).
+ </p>
+ <p>
+ The <span class="code">state</span> field is a mask of the buttons held down during
+ the event. It is a bitwise OR of any of the following (from the xcb_button_mask_t and
+ xcb_mod_mask_t enumerations):
+ </p>
+ <ul>
+ <li><span class="code">XCB_BUTTON_MASK_1</span>
+ <li><span class="code">XCB_BUTTON_MASK_2</span>
+ <li><span class="code">XCB_BUTTON_MASK_3</span>
+ <li><span class="code">XCB_BUTTON_MASK_4</span>
+ <li><span class="code">XCB_BUTTON_MASK_5</span>
+ <li><span class="code">XCB_MOD_MASK_SHIFT</span>
+ <li><span class="code">XCB_MOD_MASK_LOCK</span>
+ <li><span class="code">XCB_MOD_MASK_CONTROL</span>
+ <li><span class="code">XCB_MOD_MASK_1</span>
+ <li><span class="code">XCB_MOD_MASK_2</span>
+ <li><span class="code">XCB_MOD_MASK_3</span>
+ <li><span class="code">XCB_MOD_MASK_4</span>
+ <li><span class="code">XCB_MOD_MASK_5</span>
+ </ul>
+ <p>
+ Their names are self explanatory, where the first 5 refer to
+ the mouse buttons that are being pressed, while the rest
+ refer to various "special keys" that are being pressed (Mod1
+ is usually the 'Alt' key or the 'Meta' key).
+ </p>
+ <p>
+ <b>TODO:</b> Problem: it seems that the state does not
+ change when clicking with various buttons.
+ </p>
+ <li class="subsubtitle"><a name="mousemvnt">Mouse movement events</a>
+ <p>
+ Similar to mouse button press and release events, we also
+ can be notified of various mouse movement events. These can
+ be split into two families. One is of mouse pointer
+ movement while no buttons are pressed, and the second is a
+ mouse pointer motion while one (or more) of the buttons are
+ pressed (this is sometimes called "a mouse drag operation",
+ or just "dragging"). The following event masks may be added
+ during the creation of our window:
+ </p>
+ <ul>
+ <li><span class="code">XCB_EVENT_MASK_POINTER_MOTION</span>: events of
+ the pointer moving in one of the windows controlled by our
+ application, while no mouse button is held pressed.
+ <li><span class="code">XCB_EVENT_MASK_BUTTON_MOTION</span>: Events of
+ the pointer moving while one or more of the mouse buttons
+ is held pressed.
+ <li><span class="code">XCB_EVENT_MASK_BUTTON_1_MOTION</span>: same as
+ <span class="code">XCB_EVENT_MASK_BUTTON_MOTION</span>, but only when
+ the 1st mouse button is held pressed.
+ <li><span class="code">XCB_EVENT_MASK_BUTTON_2_MOTION</span>,
+ <span class="code">XCB_EVENT_MASK_BUTTON_3_MOTION</span>,
+ <span class="code">XCB_EVENT_MASK_BUTTON_4_MOTION</span>,
+ <span class="code">XCB_EVENT_MASK_BUTTON_5_MOTION</span>: same as
+ <span class="code">XCB_EVENT_MASK_BUTTON_1_MOTION</span>, but
+ respectively for 2nd, 3rd, 4th and 5th mouse button.
+ </ul>
+ <p>
+ The structure to be checked for in our events loop is the
+ same for these events, and is the following:
+ </p>
+ <pre class="code">
+typedef struct {
+ uint8_t response_type; /* The type of the event */
+ uint8_t detail;
+ uint16_t sequence;
+ xcb_timestamp_t time; /* Time, in milliseconds the event took place in */
+ xcb_window_t root;
+ xcb_window_t event;
+ xcb_window_t child;
+ int16_t root_x;
+ int16_t root_y;
+ int16_t event_x; /* The x coordinate of the mouse when the event was generated */
+ int16_t event_y; /* The y coordinate of the mouse when the event was generated */
+ uint16_t state; /* A mask of the buttons (or keys) during the event */
+ uint8_t same_screen;
+} xcb_motion_notify_event_t;
+</pre>
+ <li class="subsubtitle"><a name="mouseenter">Mouse pointer enter and leave events</a>
+ <p>
+ Another type of event that applications might be interested
+ in, is a mouse pointer entering a window the program
+ controls, or leaving such a window. Some programs use these
+ events to show the user that the application is now in
+ focus. In order to register for such an event type, we
+ should add one (or more) of the following masks when we
+ create our window:
+ </p>
+ <ul>
+ <li><span class="code">xcb_event_enter_window_t</span>: notify us
+ when the mouse pointer enters any of our controlled
+ windows.
+ <li><span class="code">xcb_event_leave_window_t</span>: notify us
+ when the mouse pointer leaves any of our controlled
+ windows.
+ </ul>
+ <p>
+ The structure to be checked for in our events loop is the
+ same for these two events, and is the following:
+ </p>
+ <pre class="code">
+typedef struct {
+ uint8_t response_type; /* The type of the event */
+ uint8_t detail;
+ uint16_t sequence;
+ xcb_timestamp_t time; /* Time, in milliseconds the event took place in */
+ xcb_window_t root;
+ xcb_window_t event;
+ xcb_window_t child;
+ int16_t root_x;
+ int16_t root_y;
+ int16_t event_x; /* The x coordinate of the mouse when the event was generated */
+ int16_t event_y; /* The y coordinate of the mouse when the event was generated */
+ uint16_t state; /* A mask of the buttons (or keys) during the event */
+ uint8_t mode; /* The number of mouse button that was clicked */
+ uint8_t same_screen_focus;
+} xcb_enter_notify_event_t;
+
+typedef xcb_enter_notify_event_t xcb_leave_notify_event_t;
+</pre>
+ <li class="subsubtitle"><a name="focus">The keyboard focus</a>
+ <p>
+ There may be many windows on a screen, but only a single
+ keyboard attached to them. How does the X server then know
+ which window should be sent a given keyboard input ? This is
+ done using the keyboard focus. Only a single window on the
+ screen may have the keyboard focus at a given time. There
+ is a XCB function that allows a program to set the keyboard
+ focus to a given window. The user can usually set the
+ keyboard focus using the window manager (often by clicking
+ on the title bar of the desired window). Once our window
+ has the keyboard focus, every key press or key release will
+ cause an event to be sent to our program (if it regsitered
+ for these event types...).
+ </p>
+ <li class="subsubtitle"><a name="keypress">Keyboard press and release events</a>
+ <p>
+ If a window controlled by our program currently holds the
+ keyboard focus, it can receive key press and key release
+ events. So, we should add one (or more) of the following
+ masks when we create our window:
+ </p>
+ <ul>
+ <li><span class="code">XCB_EVENT_MASK_KEY_PRESS</span>: notify us when
+ a key was pressed while any of our controlled windows had
+ the keyboard focus.
+ <li><span class="code">XCB_EVENT_MASK_KEY_RELEASE</span>: notify us
+ when a key was released while any of our controlled
+ windows had the keyboard focus.
+ </ul>
+ <p>
+ The structure to be checked for in our events loop is the
+ same for these two events, and is the following:
+ </p>
+ <pre class="code">
+typedef struct {
+ uint8_t response_type; /* The type of the event */
+ xcb_keycode_t detail;
+ uint16_t sequence;
+ xcb_timestamp_t time; /* Time, in milliseconds the event took place in */
+ xcb_window_t root;
+ xcb_window_t event;
+ xcb_window_t child;
+ int16_t root_x;
+ int16_t root_y;
+ int16_t event_x;
+ int16_t event_y;
+ uint16_t state;
+ uint8_t same_screen;
+} xcb_key_press_event_t;
+
+typedef xcb_key_press_event_t xcb_key_release_event_t;
+</pre>
+ <p>
+ The <span class="code">detail</span> field refers to the
+ physical key on the keyboard.
+ </p>
+ <p>
+ <b>TODO:</b> Talk about getting the ASCII code from the key code.
+ </p>
+ </ol>
+ <li class="subtitle"><a name="eventex">X events: a complete example</a>
+ <p>
+ As an example for handling events, we show a program that
+ creates a window, enters an events loop and checks for all the
+ events described above, and writes on the terminal the relevant
+ characteristics of the event. With this code, it should be
+ easy to add drawing operations, like those which have been
+ described above.
+ </p>
+ <pre class="code">
+#include &lt;stdlib.h&gt;
+#include &lt;stdio.h&gt;
+
+#include &lt;xcb/xcb.h&gt;
+
+void
+print_modifiers (uint32_t mask)
+{
+ const char **mod, *mods[] = {
+ "Shift", "Lock", "Ctrl", "Alt",
+ "Mod2", "Mod3", "Mod4", "Mod5",
+ "Button1", "Button2", "Button3", "Button4", "Button5"
+ };
+ printf ("Modifier mask: ");
+ for (mod = mods ; mask; mask &gt;&gt;= 1, mod++)
+ if (mask &amp; 1)
+ printf(*mod);
+ putchar ('\n');
+}
+
+int
+main ()
+{
+ xcb_connection_t *c;
+ xcb_screen_t *screen;
+ xcb_window_t win;
+ xcb_generic_event_t *e;
+ uint32_t mask = 0;
+ uint32_t values[2];
+
+ /* Open the connection to the X server */
+ c = xcb_connect (NULL, NULL);
+
+ /* Get the first screen */
+ screen = xcb_setup_roots_iterator (xcb_get_setup (c)).data;
+
+ /* Ask for our window's Id */
+ win = xcb_generate_id (c);
+
+ /* Create the window */
+ mask = XCB_CW_BACK_PIXEL | XCB_CW_EVENT_MASK;
+ values[0] = screen-&gt;white_pixel;
+ values[1] = XCB_EVENT_MASK_EXPOSURE | XCB_EVENT_MASK_BUTTON_PRESS |
+ XCB_EVENT_MASK_BUTTON_RELEASE | XCB_EVENT_MASK_POINTER_MOTION |
+ XCB_EVENT_MASK_ENTER_WINDOW | XCB_EVENT_MASK_LEAVE_WINDOW |
+ XCB_EVENT_MASK_KEY_PRESS | XCB_EVENT_MASK_KEY_RELEASE;
+ xcb_create_window (c, /* Connection */
+ 0, /* depth */
+ win, /* window Id */
+ screen-&gt;root, /* parent window */
+ 0, 0, /* x, y */
+ 150, 150, /* width, height */
+ 10, /* border_width */
+ XCB_WINDOW_CLASS_INPUT_OUTPUT, /* class */
+ screen-&gt;root_visual, /* visual */
+ mask, values); /* masks */
+
+ /* Map the window on the screen */
+ xcb_map_window (c, win);
+
+ xcb_flush (c);
+
+ while ((e = xcb_wait_for_event (c))) {
+ switch (e-&gt;response_type &amp; ~0x80) {
+ case XCB_EXPOSE: {
+ xcb_expose_event_t *ev = (xcb_expose_event_t *)e;
+
+ printf ("Window %ld exposed. Region to be redrawn at location (%d,%d), with dimension (%d,%d)\n",
+ ev-&gt;window, ev-&gt;x, ev-&gt;y, ev-&gt;width, ev-&gt;height);
+ break;
+ }
+ case XCB_BUTTON_PRESS: {
+ xcb_button_press_event_t *ev = (xcb_button_press_event_t *)e;
+ print_modifiers(ev-&gt;state);
+
+ switch (ev-&gt;detail) {
+ case 4:
+ printf ("Wheel Button up in window %ld, at coordinates (%d,%d)\n",
+ ev-&gt;event, ev-&gt;event_x, ev-&gt;event_y);
+ break;
+ case 5:
+ printf ("Wheel Button down in window %ld, at coordinates (%d,%d)\n",
+ ev-&gt;event, ev-&gt;event_x, ev-&gt;event_y);
+ break;
+ default:
+ printf ("Button %d pressed in window %ld, at coordinates (%d,%d)\n",
+ ev-&gt;detail, ev-&gt;event, ev-&gt;event_x, ev-&gt;event_y);
+ }
+ break;
+ }
+ case XCB_BUTTON_RELEASE: {
+ xcb_button_release_event_t *ev = (xcb_button_release_event_t *)e;
+ print_modifiers(ev-&gt;state);
+
+ printf ("Button %d released in window %ld, at coordinates (%d,%d)\n",
+ ev-&gt;detail, ev-&gt;event, ev-&gt;event_x, ev-&gt;event_y);
+ break;
+ }
+ case XCB_MOTION_NOTIFY: {
+ xcb_motion_notify_event_t *ev = (xcb_motion_notify_event_t *)e;
+
+ printf ("Mouse moved in window %ld, at coordinates (%d,%d)\n",
+ ev-&gt;event, ev-&gt;event_x, ev-&gt;event_y);
+ break;
+ }
+ case XCB_ENTER_NOTIFY: {
+ xcb_enter_notify_event_t *ev = (xcb_enter_notify_event_t *)e;
+
+ printf ("Mouse entered window %ld, at coordinates (%d,%d)\n",
+ ev-&gt;event, ev-&gt;event_x, ev-&gt;event_y);
+ break;
+ }
+ case XCB_LEAVE_NOTIFY: {
+ xcb_leave_notify_event_t *ev = (xcb_leave_notify_event_t *)e;
+
+ printf ("Mouse left window %ld, at coordinates (%d,%d)\n",
+ ev-&gt;event, ev-&gt;event_x, ev-&gt;event_y);
+ break;
+ }
+ case XCB_KEY_PRESS: {
+ xcb_key_press_event_t *ev = (xcb_key_press_event_t *)e;
+ print_modifiers(ev-&gt;state);
+
+ printf ("Key pressed in window %ld\n",
+ ev-&gt;event);
+ break;
+ }
+ case XCB_KEY_RELEASE: {
+ xcb_key_release_event_t *ev = (xcb_key_release_event_t *)e;
+ print_modifiers(ev-&gt;state);
+
+ printf ("Key released in window %ld\n",
+ ev-&gt;event);
+ break;
+ }
+ default:
+ /* Unknown event type, ignore it */
+ printf("Unknown event: %d\n", e-&gt;response_type);
+ break;
+ }
+ /* Free the Generic Event */
+ free (e);
+ }
+
+ return 0;
+}
+</pre>
+ </ol>
+ <li class="title"><a name="font">Handling text and fonts</a>
+ <p>
+ Besides drawing graphics on a window, we often want to draw
+ text. Text strings have two major properties: the characters to
+ be drawn and the font with which they are drawn. In order to
+ draw text, we need to first request the X server to load a
+ font. We then assign a font to a Graphic Context, and finally, we
+ draw the text in a window, using the Graphic Context.
+ </p>
+ <ol>
+ <li class="subtitle"><a name="fontstruct">The Font structure</a>
+ <p>
+ In order to support flexible fonts, a font type is
+ defined. You know what ? It's an Id:
+ </p>
+ <pre class="code">
+typedef uint32_t xcb_font_t;
+</pre>
+ <p>
+ It is used to contain information about a font, and is passed
+ to several functions that handle fonts selection and text drawing.
+ We ask the X server to attribute an Id to our font with the
+ function:
+ </p>
+ <pre class="code">
+xcb_font_t xcb_generate_id (xcb_connection_t *c);
+</pre>
+ <br>
+ <li class="subtitle"><a name="openingfont">Opening a Font</a>
+ <p>
+ To open a font, we use the following function:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_open_font (xcb_connection_t *c,
+ xcb_font_t fid,
+ uint16_t name_len,
+ const char *name);
+</pre>
+ <p>
+ The <span class="code">fid</span> parameter is the font Id
+ defined by <span class="code">xcb_generate_id()</span> (see
+ above). The <span class="code">name</span> parameter is the
+ name of the font you want to open. Use the command
+ <span class="code">xlsfonts</span> in a terminal to know which
+ are the fonts available on your computer. The parameter
+ <span class="code">name_len</span> is the length of the name
+ of the font (given by <span class="code">strlen()</span>).
+ </p>
+ <li class="subtitle"><a name="assigningfont">Assigning a Font to a Graphic Context</a>
+ <p>
+ Once a font is opened, you have to create a Graphic Context
+ that will contain the informations about the color of the
+ foreground and the background used when you draw a text in a
+ Drawable. Here is an exemple of a Graphic Context that will
+ allow us to draw an opened font with a black foreground and a
+ white background:
+ </p>
+ <pre class="code">
+ /*
+ * c is the connection
+ * screen is the screen where the window is displayed
+ * window is the window in which we will draw the text
+ * font is the opened font
+ */
+
+ uint32_t value_list[3];
+ xcb_gcontext_t gc;
+ uint32_t mask;
+
+ gc = xcb_generate_id (c);
+ mask = XCB_GC_FOREGROUND | XCB_GC_BACKGROUND | XCB_GC_FONT;
+ value_list[0] = screen->black_pixel;
+ value_list[1] = screen->white_pixel;
+ value_list[2] = font;
+ xcb_create_gc (c, gc, window, mask, value_list);
+
+ /* The font is not needed anymore, so we close it */
+ xcb_close_font (c, font);
+</pre>
+ <li class="subtitle"><a name="drawingtext">Drawing text in a drawable</a>
+ <p>
+ To draw a text in a drawable, we use the following function:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_image_text_8 (xcb_connection_t *c,
+ uint8_t string_len,
+ xcb_drawable_t drawable,
+ xcb_gcontext_t gc,
+ int16_t x,
+ int16_t y,
+ const char *string);
+</pre>
+ <p>
+ The <span class="code">string</span> parameter is the text to
+ draw. The location of the drawing is given by the parameters
+ <span class="code">x</span> and <span class="code">y</span>.
+ The base line of the text is exactly the parameter
+ <span class="code">y</span>.
+ </p>
+ <li class="subtitle"><a name="fontcompleteexample">Complete example</a>
+ <p>
+ This example draw a text at 10 pixels (for the base line) of
+ the bottom of a window. Pressing the Esc key exits the program.
+ </p>
+ <pre class="code">
+#include &lt;stdlib.h&gt;
+#include &lt;stdio.h&gt;
+#include &lt;string.h&gt;
+
+#include &lt;xcb/xcb.h&gt;
+
+#define WIDTH 300
+#define HEIGHT 100
+
+
+
+static xcb_gc_t gc_font_get (xcb_connection_t *c,
+ xcb_screen_t *screen,
+ xcb_window_t window,
+ const char *font_name);
+
+static void text_draw (xcb_connection_t *c,
+ xcb_screen_t *screen,
+ xcb_window_t window,
+ int16_t x1,
+ int16_t y1,
+ const char *label);
+
+static void
+text_draw (xcb_connection_t *c,
+ xcb_screen_t *screen,
+ xcb_window_t window,
+ int16_t x1,
+ int16_t y1,
+ const char *label)
+{
+ xcb_void_cookie_t cookie_gc;
+ xcb_void_cookie_t cookie_text;
+ xcb_generic_error_t *error;
+ xcb_gcontext_t gc;
+ uint8_t length;
+
+ length = strlen (label);
+
+ gc = gc_font_get(c, screen, window, "7x13");
+
+ cookie_text = xcb_image_text_8_checked (c, length, window, gc,
+ x1,
+ y1, label);
+ error = xcb_request_check (c, cookie_text);
+ if (error) {
+ fprintf (stderr, "ERROR: can't paste text : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+
+ cookie_gc = xcb_free_gc (c, gc);
+ error = xcb_request_check (c, cookie_gc);
+ if (error) {
+ fprintf (stderr, "ERROR: can't free gc : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+}
+
+static xcb_gc_t
+gc_font_get (xcb_connection_t *c,
+ xcb_screen_t *screen,
+ xcb_window_t window,
+ const char *font_name)
+{
+ uint32_t value_list[3];
+ xcb_void_cookie_t cookie_font;
+ xcb_void_cookie_t cookie_gc;
+ xcb_generic_error_t *error;
+ xcb_font_t font;
+ xcb_gcontext_t gc;
+ uint32_t mask;
+
+ font = xcb_generate_id (c);
+ cookie_font = xcb_open_font_checked (c, font,
+ strlen (font_name),
+ font_name);
+
+ error = xcb_request_check (c, cookie_font);
+ if (error) {
+ fprintf (stderr, "ERROR: can't open font : %d\n", error->error_code);
+ xcb_disconnect (c);
+ return -1;
+ }
+
+ gc = xcb_generate_id (c);
+ mask = XCB_GC_FOREGROUND | XCB_GC_BACKGROUND | XCB_GC_FONT;
+ value_list[0] = screen->black_pixel;
+ value_list[1] = screen->white_pixel;
+ value_list[2] = font;
+ cookie_gc = xcb_create_gc_checked (c, gc, window, mask, value_list);
+ error = xcb_request_check (c, cookie_gc);
+ if (error) {
+ fprintf (stderr, "ERROR: can't create gc : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+
+ cookie_font = xcb_close_font_checked (c, font);
+ error = xcb_request_check (c, cookie_font);
+ if (error) {
+ fprintf (stderr, "ERROR: can't close font : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+
+ return gc;
+}
+
+int main ()
+{
+ xcb_screen_iterator_t screen_iter;
+ xcb_connection_t *c;
+ const xcb_setup_t *setup;
+ xcb_screen_t *screen;
+ xcb_generic_event_t *e;
+ xcb_generic_error_t *error;
+ xcb_void_cookie_t cookie_window;
+ xcb_void_cookie_t cookie_map;
+ xcb_window_t window;
+ uint32_t mask;
+ uint32_t values[2];
+ int screen_number;
+
+ /* getting the connection */
+ c = xcb_connect (NULL, &amp;screen_number);
+ if (!c) {
+ fprintf (stderr, "ERROR: can't connect to an X server\n");
+ return -1;
+ }
+
+ /* getting the current screen */
+ setup = xcb_get_setup (c);
+
+ screen = NULL;
+ screen_iter = xcb_setup_roots_iterator (setup);
+ for (; screen_iter.rem != 0; --screen_number, xcb_screen_next (&amp;screen_iter))
+ if (screen_number == 0)
+ {
+ screen = screen_iter.data;
+ break;
+ }
+ if (!screen) {
+ fprintf (stderr, "ERROR: can't get the current screen\n");
+ xcb_disconnect (c);
+ return -1;
+ }
+
+ /* creating the window */
+ window = xcb_generate_id (c);
+ mask = XCB_CW_BACK_PIXEL | XCB_CW_EVENT_MASK;
+ values[0] = screen->white_pixel;
+ values[1] =
+ XCB_EVENT_MASK_KEY_RELEASE |
+ XCB_EVENT_MASK_BUTTON_PRESS |
+ XCB_EVENT_MASK_EXPOSURE |
+ XCB_EVENT_MASK_POINTER_MOTION;
+ cookie_window = xcb_create_window_checked (c,
+ screen->root_depth,
+ window, screen->root,
+ 20, 200, WIDTH, HEIGHT,
+ 0, XCB_WINDOW_CLASS_INPUT_OUTPUT,
+ screen->root_visual,
+ mask, values);
+ cookie_map = xcb_map_window_checked (c, window);
+
+ /* error managing */
+ error = xcb_request_check (c, cookie_window);
+ if (error) {
+ fprintf (stderr, "ERROR: can't create window : %d\n", error->error_code);
+ xcb_disconnect (c);
+ return -1;
+ }
+ error = xcb_request_check (c, cookie_map);
+ if (error) {
+ fprintf (stderr, "ERROR: can't map window : %d\n", error->error_code);
+ xcb_disconnect (c);
+ return -1;
+ }
+
+ xcb_flush(c);
+
+ while (1) {
+ e = xcb_poll_for_event(c);
+ if (e) {
+ switch (e->response_type &amp; ~0x80) {
+ case XCB_EXPOSE: {
+ char *text;
+
+ text = "Press ESC key to exit...";
+ text_draw (c, screen, window, 10, HEIGHT - 10, text);
+ break;
+ }
+ case XCB_KEY_RELEASE: {
+ xcb_key_release_event_t *ev;
+
+ ev = (xcb_key_release_event_t *)e;
+
+ switch (ev->detail) {
+ /* ESC */
+ case 9:
+ free (e);
+ xcb_disconnect (c);
+ return 0;
+ }
+ }
+ }
+ free (e);
+ }
+ }
+
+ return 0;
+}
+</pre>
+ </ol>
+ <li class="title"><a name="wm">Interacting with the window manager</a>
+ <p>
+ After we have seen how to create windows and draw on them, we
+ take one step back, and look at how our windows are interacting
+ with their environment (the full screen and the other
+ windows). First of all, our application needs to interact with
+ the window manager. The window manager is responsible to
+ decorating drawn windows (i.e. adding a frame, an iconify
+ button, a system menu, a title bar, etc), as well as handling
+ icons shown when windows are being iconified. It also handles
+ ordering of windows on the screen, and other administrative
+ tasks. We need to give it various hints as to how we want it to
+ treat our application's windows.
+ </p>
+ <ol>
+ <li class="subtitle"><a name="wmprop">Window properties</a>
+ <p>
+ Many of the parameters communicated to the window manager are
+ passed using data called "properties". These properties are
+ attached by the X server to different windows, and are stored
+ in a format that makes it possible to read them from different
+ machines that may use different architectures (remember that
+ an X client program may run on a remote machine).
+ </p>
+ <p>
+ The property and its type (a string, an integer, etc) are
+ Id. Their type are <span class="code">xcb_atom_t</span>:
+ </p>
+ <pre class="code">
+typedef uint32_t xcb_atom_t;
+</pre>
+ <p>
+ To change the property of a window, we use the following
+ function:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_change_property (xcb_connection_t *c, /* Connection to the X server */
+ uint8_t mode, /* Property mode */
+ xcb_window_t window, /* Window */
+ xcb_atom_t property, /* Property to change */
+ xcb_atom_t type, /* Type of the property */
+ uint8_t format, /* Format of the property (8, 16, 32) */
+ uint32_t data_len, /* Length of the data parameter */
+ const void *data); /* Data */
+</pre>
+ <p>
+ The <span class="code">mode</span> parameter coud be one of
+ the following values (defined in enumeration xcb_prop_mode_t in
+ the xproto.h header file):
+ </p>
+ <ul>
+ <li>XCB_PROP_MODE_REPLACE
+ <li>XCB_PROP_MODE_PREPEND
+ <li>XCB_PROP_MODE_APPEND
+ </ul>
+ <br>
+ <li class="subtitle"><a name="wmname">Setting the window name and icon name</a>
+ <p>
+ The first thing we want to do would be to set the name for our
+ window. This is done using the
+ <span class="code">xcb_change_property()</span> function. This
+ name may be used by the window manager as the title of the
+ window (in the title bar), in a task list, etc. The property
+ atom to use to set the name of a window is
+ <span class="code">WM_NAME</span> (and
+ <span class="code">WM_ICON_NAME</span> for the iconified
+ window) and its type is <span class="code">STRING</span>. Here
+ is an example of utilization:
+ </p>
+ <pre class="code">
+#include &lt;string.h&gt;
+
+#include &lt;xcb/xcb.h&gt;
+#include &lt;xcb/xcb_atom.h&gt;
+
+int
+main ()
+{
+ xcb_connection_t *c;
+ xcb_screen_t *screen;
+ xcb_window_t win;
+ char *title = "Hello World !";
+ char *title_icon = "Hello World ! (iconified)";
+
+
+
+ /* Open the connection to the X server */
+ c = xcb_connect (NULL, NULL);
+
+ /* Get the first screen */
+ screen = xcb_setup_roots_iterator (xcb_get_setup (c)).data;
+
+ /* Ask for our window's Id */
+ win = xcb_generate_id (c);
+
+ /* Create the window */
+ xcb_create_window (c, /* Connection */
+ 0, /* depth */
+ win, /* window Id */
+ screen-&gt;root, /* parent window */
+ 0, 0, /* x, y */
+ 250, 150, /* width, height */
+ 10, /* border_width */
+ XCB_WINDOW_CLASS_INPUT_OUTPUT, /* class */
+ screen-&gt;root_visual, /* visual */
+ 0, NULL); /* masks, not used */
+
+ /* Set the title of the window */
+ xcb_change_property (c, XCB_PROP_MODE_REPLACE, win,
+ WM_NAME, STRING, 8,
+ strlen (title), title);
+
+ /* Set the title of the window icon */
+ xcb_change_property (c, XCB_PROP_MODE_REPLACE, win,
+ WM_ICON_NAME, STRING, 8,
+ strlen(title_icon), title_icon);
+
+ /* Map the window on the screen */
+ xcb_map_window (c, win);
+
+ xcb_flush (c);
+
+ while (1) {}
+
+ return 0;
+}
+</pre>
+ <div class="emph">
+ <p>Note: the use of the atoms needs our program to be compiled
+ and linked against xcb_atom, so that we have to use
+ </p>
+ </div>
+ <pre class="text">
+gcc prog.c -o prog `pkg-config --cflags --libs xcb_atom`
+</pre>
+ <div class="emph">
+ <p>
+ for the program to compile fine.
+ </p>
+ </div>
+ </ol>
+ <li class="title"><a name="winop">Simple window operations</a>
+ <p>
+ One more thing we can do to our window is manipulate them on the
+ screen (resize them, move them, raise or lower them, iconify
+ them, and so on). Some window operations functions are supplied
+ by XCB for this purpose.
+ </p>
+ <ol>
+ <li class="subtitle"><a name="winmap">Mapping and un-mapping a window</a>
+ <p>
+ The first pair of operations we can apply on a window is
+ mapping it, or un-mapping it. Mapping a window causes the
+ window to appear on the screen, as we have seen in our simple
+ window program example. Un-mapping it causes it to be removed
+ from the screen (although the window as a logical entity still
+ exists). This gives the effect of making a window hidden
+ (unmapped) and shown again (mapped). For example, if we have a
+ dialog box window in our program, instead of creating it every
+ time the user asks to open it, we can create the window once,
+ in an un-mapped mode, and when the user asks to open it, we
+ simply map the window on the screen. When the user clicked the
+ 'OK' or 'Cancel' button, we simply un-map the window. This is
+ much faster than creating and destroying the window, however,
+ the cost is wasted resources, both on the client side, and on
+ the X server side.
+ </p>
+ <p>
+ To map a window, you use the following function:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_map_window (xcb_connection_t *c,
+ xcb_window_t window);
+</pre>
+ <p>
+ To have a simple example, see the <a href="#helloworld">example</a>
+ above. The mapping operation will cause an
+ <span class="code">Expose</span> event to be sent to our
+ application, unless the window is completely covered by other
+ windows.
+ </p>
+ <p>
+ Un-mapping a window is also simple. You use the function
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_unmap_window (xcb_connection_t *c,
+ xcb_window_t window);
+</pre>
+ <p>
+ The utilization of this function is the same as
+ <span class="code">xcb_map_window()</span>.
+ </p>
+ <li class="subtitle"><a name="winconf">Configuring a window</a>
+ <p>
+ As we have seen when we have created our first window, in the
+ X Events subsection, we can set some attributes for the window
+ (that is, the position, the size, the events the window will
+ receive, etc). If we want to modify them, but the window is
+ already created, we can change them by using the following
+ function:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_configure_window (xcb_connection_t *c, /* The connection to the X server*/
+ xcb_window_t window, /* The window to configure */
+ uint16_t value_mask, /* The mask */
+ const uint32_t *value_list); /* The values to set */
+</pre>
+ <p>
+ We set the <span class="code">value_mask</span> to one or
+ several mask values that are in the xcb_config_window_t enumeration in the xproto.h header:
+ </p>
+ <ul>
+ <li><span class="code">XCB_CONFIG_WINDOW_X</span>: new x coordinate of the window's top left corner
+ <li><span class="code">XCB_CONFIG_WINDOW_Y</span>: new y coordinate of the window's top left corner
+ <li><span class="code">XCB_CONFIG_WINDOW_WIDTH</span>: new width of the window
+ <li><span class="code">XCB_CONFIG_WINDOW_HEIGHT</span>: new height of the window
+ <li><span class="code">XCB_CONFIG_WINDOW_BORDER_WIDTH</span>: new width of the border of the window
+ <li><span class="code">XCB_CONFIG_WINDOW_SIBLING</span>
+ <li><span class="code">XCB_CONFIG_WINDOW_STACK_MODE</span>: the new stacking order
+ </ul>
+ <p>
+ We then give to <span class="code">value_mask</span> the new
+ value. We now describe how to use
+ <span class="code">xcb_configure_window_t</span> in some useful
+ situations.
+ </p>
+ <li class="subtitle"><a name="winmove">Moving a window around the screen</a>
+ <p>
+ An operation we might want to do with windows is to move them
+ to a different location. This can be done like this:
+ </p>
+ <pre class="code">
+const static uint32_t values[] = { 10, 20 };
+
+/* The connection c and the window win are supposed to be defined */
+
+/* Move the window to coordinates x = 10 and y = 20 */
+xcb_configure_window (c, win, XCB_CONFIG_WINDOW_X | XCB_CONFIG_WINDOW_Y, values);
+</pre>
+ <p>
+ Note that when the window is moved, it might get partially
+ exposed or partially hidden by other windows, and thus we
+ might get <span class="code">Expose</span> events due to this
+ operation.
+ </p>
+ <li class="subtitle"><a name="winsize">Resizing a window</a>
+ <p>
+ Yet another operation we can do is to change the size of a
+ window. This is done using the following code:
+ </p>
+ <pre class="code">
+const static uint32_t values[] = { 200, 300 };
+
+/* The connection c and the window win are supposed to be defined */
+
+/* Resize the window to width = 10 and height = 20 */
+xcb_configure_window (c, win, XCB_CONFIG_WINDOW_WIDTH | XCB_CONFIG_WINDOW_HEIGHT, values);
+</pre>
+ <p>
+ We can also combine the move and resize operations using one
+ single call to <span class="code">xcb_configure_window_t</span>:
+ </p>
+ <pre class="code">
+const static uint32_t values[] = { 10, 20, 200, 300 };
+
+/* The connection c and the window win are supposed to be defined */
+
+/* Move the window to coordinates x = 10 and y = 20 */
+/* and resize the window to width = 10 and height = 20 */
+xcb_configure_window (c, win, XCB_CONFIG_WINDOW_X | XCB_CONFIG_WINDOW_Y | XCB_CONFIG_WINDOW_WIDTH | XCB_CONFIG_WINDOW_HEIGHT, values);
+</pre>
+ <li class="subtitle"><a name="winstack">Changing windows stacking order: raise and lower</a>
+ <p>
+ Until now, we changed properties of a single window. We'll see
+ that there are properties that relate to the window and other
+ windows. One of them is the stacking order. That is, the order
+ in which the windows are layered on top of each other. The
+ front-most window is said to be on the top of the stack, while
+ the back-most window is at the bottom of the stack. Here is
+ how to manipulate our windows stack order:
+ </p>
+ <pre class="code">
+const static uint32_t values[] = { XCB_STACK_MODE_ABOVE };
+
+/* The connection c and the window win are supposed to be defined */
+
+/* Move the window on the top of the stack */
+xcb_configure_window (c, win, XCB_CONFIG_WINDOW_STACK_MODE, values);
+</pre>
+ <pre class="code">
+const static uint32_t values[] = { XCB_STACK_MODE_BELOW };
+
+/* The connection c and the window win are supposed to be defined */
+
+/* Move the window on the bottom of the stack */
+xcb_configure_window (c, win, XCB_CONFIG_WINDOW_STACK_MODE, values);
+</pre>
+ <li class="subtitle"><a name="wingetinfo">Getting information about a window</a>
+ <p>
+ Just like we can set various attributes of our windows, we can
+ also ask the X server supply the current values of these
+ attributes. For example, we can check where a window is
+ located on the screen, what is its current size, whether it is
+ mapped or not, etc. The structure that contains some of this
+ information is
+ </p>
+ <pre class="code">
+typedef struct {
+ uint8_t response_type;
+ uint8_t depth; /* depth of the window */
+ uint16_t sequence;
+ uint32_t length;
+ xcb_window_t root; /* Id of the root window *>
+ int16_t x; /* X coordinate of the window's location */
+ int16_t y; /* Y coordinate of the window's location */
+ uint16_t width; /* Width of the window */
+ uint16_t height; /* Height of the window */
+ uint16_t border_width; /* Width of the window's border */
+} xcb_get_geometry_reply_t;
+</pre>
+ <p>
+ XCB fill this structure with two functions:
+ </p>
+ <pre class="code">
+xcb_get_geometry_cookie_t xcb_get_geometry (xcb_connection_t *c,
+ xcb_drawable_t drawable);
+xcb_get_geometry_reply_t *xcb_get_geometry_reply (xcb_connection_t *c,
+ xcb_get_geometry_cookie_t cookie,
+ xcb_generic_error_t **e);
+</pre>
+ <p>
+ You use them as follows:
+ </p>
+ <pre class="code">
+ xcb_connection_t *c;
+ xcb_drawable_t win;
+ xcb_get_geometry_reply_t *geom;
+
+ /* You initialize c and win */
+
+ geom = xcb_get_geometry_reply (c, xcb_get_geometry (c, win), NULL);
+
+ /* Do something with the fields of geom */
+
+ free (geom);
+</pre>
+ <p>
+ Remark that you have to free the structure, as
+ <span class="code">xcb_get_geometry_reply_t</span> allocates a
+ newly one.
+ </p>
+ <p>
+ One problem is that the returned location of the window is
+ relative to its parent window. This makes these coordinates
+ rather useless for any window manipulation functions, like
+ moving it on the screen. In order to overcome this problem, we
+ need to take a two-step operation. First, we find out the Id
+ of the parent window of our window. We then translate the
+ above relative coordinates to the screen coordinates.
+ </p>
+ <p>
+ To get the Id of the parent window, we need this structure:
+ </p>
+ <pre class="code">
+typedef struct {
+ uint8_t response_type;
+ uint8_t pad0;
+ uint16_t sequence;
+ uint32_t length;
+ xcb_window_t root;
+ xcb_window_t parent; /* Id of the parent window */
+ uint16_t children_len;
+ uint8_t pad1[14];
+} xcb_query_tree_reply_t;
+</pre>
+ <p>
+ To fill this structure, we use these two functions:
+ </p>
+ <pre class="code">
+xcb_query_tree_cookie_t xcb_query_tree (xcb_connection_t *c,
+ xcb_window_t window);
+xcb_query_tree_reply_t *xcb_query_tree_reply (xcb_connection_t *c,
+ xcb_query_tree_cookie_t cookie,
+ xcb_generic_error_t **e);
+</pre>
+ <p>
+ The translated coordinates will be found in this structure:
+ </p>
+ <pre class="code">
+typedef struct {
+ uint8_t response_type;
+ uint8_t same_screen;
+ uint16_t sequence;
+ uint32_t length;
+ xcb_window_t child;
+ uint16_t dst_x; /* Translated x coordinate */
+ uint16_t dst_y; /* Translated y coordinate */
+} xcb_translate_coordinates_reply_t;
+</pre>
+ <p>
+ As usual, we need two functions to fill this structure:
+ </p>
+ <pre class="code">
+xcb_translate_coordinates_cookie_t xcb_translate_coordinates (xcb_connection_t *c,
+ xcb_window_t src_window,
+ xcb_window_t dst_window,
+ int16_t src_x,
+ int16_t src_y);
+xcb_translate_coordinates_reply_t *xcb_translate_coordinates_reply (xcb_connection_t *c,
+ xcb_translate_coordinates_cookie_t cookie,
+ xcb_generic_error_t **e);
+</pre>
+ <p>
+ We use them as follows:
+ </p>
+ <pre class="code">
+ xcb_connection_t *c;
+ xcb_drawable_t win;
+ xcb_get_geometry_reply_t *geom;
+ xcb_query_tree_reply_t *tree;
+ xcb_translate_coordinates_reply_t *trans;
+
+ /* You initialize c and win */
+
+ geom = xcb_get_geometry_reply (c, xcb_get_geometry (c, win), NULL);
+ if (!geom)
+ return 0;
+
+ tree = xcb_query_tree_reply (c, xcb_query_tree (c, win), NULL);
+ if (!tree)
+ return 0;
+
+ trans = xcb_translate_coordinates_reply (c,
+ xcb_translate_coordinates (c,
+ win,
+ tree-&gt;parent,
+ geom-&gt;x, geom-&gt;y),
+ NULL);
+ if (!trans)
+ return 0;
+
+ /* the translated coordinates are in trans-&gt;dst_x and trans-&gt;dst_y */
+
+ free (trans);
+ free (tree);
+ free (geom);
+</pre>
+ <p>
+ Of course, as for <span class="code">geom</span>,
+ <span class="code">tree</span> and
+ <span class="code">trans</span> have to be freed.
+ </p>
+ <p>
+ The work is a bit hard, but XCB is a very low-level library.
+ </p>
+ <p>
+ <b>TODO:</b> the utilization of these functions should be a
+ prog, which displays the coordinates of the window.
+ </p>
+ <p>
+ There is another structure that gives informations about our window:
+ </p>
+ <pre class="code">
+typedef struct {
+ uint8_t response_type;
+ uint8_t backing_store;
+ uint16_t sequence;
+ uint32_t length;
+ xcb_visualid_t visual; /* Visual of the window */
+ uint16_t _class;
+ uint8_t bit_gravity;
+ uint8_t win_gravity;
+ uint32_t backing_planes;
+ uint32_t backing_pixel;
+ uint8_t save_under;
+ uint8_t map_is_installed;
+ uint8_t map_state; /* Map state of the window */
+ uint8_t override_redirect;
+ xcb_colormap_t colormap; /* Colormap of the window */
+ uint32_t all_event_masks;
+ uint32_t your_event_mask;
+ uint16_t do_not_propagate_mask;
+} xcb_get_window_attributes_reply_t;
+</pre>
+ <p>
+ XCB supplies these two functions to fill it:
+ </p>
+ <pre class="code">
+xcb_get_window_attributes_cookie_t xcb_get_window_attributes (xcb_connection_t *c,
+ xcb_window_t window);
+xcb_get_window_attributes_reply_t *xcb_get_window_attributes_reply (xcb_connection_t *c,
+ xcb_get_window_attributes_cookie_t cookie,
+ xcb_generic_error_t **e);
+</pre>
+ <p>
+ You use them as follows:
+ </p>
+ <pre class="code">
+ xcb_connection_t *c;
+ xcb_drawable_t win;
+ xcb_get_window_attributes_reply_t *attr;
+
+ /* You initialize c and win */
+
+ attr = xcb_get_window_attributes_reply (c, xcb_get_window_attributes (c, win), NULL);
+
+ if (!attr)
+ return 0;
+
+ /* Do something with the fields of attr */
+
+ free (attr);
+</pre>
+ <p>
+ As for <span class="code">geom</span>,
+ <span class="code">attr</span> has to be freed.
+ </p>
+ </ol>
+ <li class="title"><a name="usecolor">Using colors to paint the rainbow</a>
+ <p>
+ Up until now, all our painting operation were done using black
+ and white. We will (finally) see now how to draw using colors.
+ </p>
+ <ol>
+ <li class="subtitle"><a name="colormap">Color maps</a>
+ <p>
+ In the beginning, there were not enough colors. Screen
+ controllers could only support a limited number of colors
+ simultaneously (initially 2, then 4, 16 and 256). Because of
+ this, an application could not just ask to draw in a "light
+ purple-red" color, and expect that color to be available. Each
+ application allocated the colors it needed, and when all the
+ color entries (4, 16, 256 colors) were in use, the next color
+ allocation would fail.
+ </p>
+ <p>
+ Thus, the notion of "a color map" was introduced. A color map
+ is a table whose size is the same as the number of
+ simultaneous colors a given screen controller. Each entry
+ contained the RGB (Red, Green and Blue) values of a different
+ color (all colors can be drawn using some combination of red,
+ green and blue). When an application wants to draw on the
+ screen, it does not specify which color to use. Rather, it
+ specifies which color entry of some color map to be used
+ during this drawing. Change the value in this color map entry
+ and the drawing will use a different color.
+ </p>
+ <p>
+ In order to be able to draw using colors that got something to
+ do with what the programmer intended, color map allocation
+ functions are supplied. You could ask to allocate entry for a
+ color with a set of RGB values. If one already existed, you
+ would get its index in the table. If none existed, and the
+ table was not full, a new cell would be allocated to contain
+ the given RGB values, and its index returned. If the table was
+ full, the procedure would fail. You could then ask to get a
+ color map entry with a color that is closest to the one you
+ were asking for. This would mean that the actual drawing on
+ the screen would be done using colors similar to what you
+ wanted, but not the same.
+ </p>
+ <p>
+ On today's more modern screens where one runs an X server with
+ support for 16 million colors, this limitation looks a little
+ silly, but remember that there are still older computers with
+ older graphics cards out there. Using color map, support for
+ these screen becomes transparent to you. On a display
+ supporting 16 million colors, any color entry allocation
+ request would succeed. On a display supporting a limited
+ number of colors, some color allocation requests would return
+ similar colors. It won't look as good, but your application
+ would still work.
+ </p>
+ <li class="subtitle"><a name="colormapalloc">Allocating and freeing Color Maps</a>
+ <p>
+ When you draw using XCB, you can choose to use the standard
+ color map of the screen your window is displayed on, or you
+ can allocate a new color map and apply it to a window. In the
+ latter case, each time the mouse moves onto your window, the
+ screen color map will be replaced by your window's color map,
+ and you'll see all the other windows on screen change their
+ colors into something quite bizzare. In fact, this is the
+ effect you get with X applications that use the "-install"
+ command line option.
+ </p>
+ <p>
+ In XCB, a color map is (as often in X) an Id:
+ </p>
+ <pre class="code">
+typedef uint32_t xcb_colormap_t;
+</pre>
+ <p>
+ In order to access the screen's default color map, you just
+ have to retrieve the <span class="code">default_colormap</span>
+ field of the <span class="code">xcb_screen_t</span> structure
+ (see Section
+ <a href="#screen">Checking basic information about a connection</a>):
+ </p>
+ <pre class="code">
+#include &lt;stdio.h&gt;
+
+#include &lt;xcb/xcb.h&gt;
+
+int
+main ()
+{
+ xcb_connection_t *c;
+ xcb_screen_t *screen;
+ xcb_colormap_t colormap;
+
+ /* Open the connection to the X server and get the first screen */
+ c = xcb_connect (NULL, NULL);
+ screen = xcb_setup_roots_iterator (xcb_get_setup (c)).data;
+
+ colormap = screen-&gt;default_colormap;
+
+ return 0;
+}
+</pre>
+ <p>
+ This will return the color map used by default on the first
+ screen (again, remember that an X server may support several
+ different screens, each of which might have its own resources).
+ </p>
+ <p>
+ The other option, that of allocating a new colormap, works as
+ follows. We first ask the X server to give an Id to our color
+ map, with this function:
+ </p>
+ <pre class="code">
+xcb_colormap_t xcb_generate_id (xcb_connection_t *c);
+</pre>
+ <p>
+ Then, we create the color map with
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_create_colormap (xcb_connection_t *c, /* Pointer to the xcb_connection_t structure */
+ uint8_t alloc, /* Colormap entries to be allocated (AllocNone or AllocAll) */
+ xcb_colormap_t mid, /* Id of the color map */
+ xcb_window_t window, /* Window on whose screen the colormap will be created */
+ xcb_visualid_t visual); /* Id of the visual supported by the screen */
+</pre>
+ <p>
+ Here is an example of creation of a new color map:
+ </p>
+ <pre class="code">
+#include &lt;xcb/xcb.h&gt;
+
+int
+main ()
+{
+ xcb_connection_t *c;
+ xcb_screen_t *screen;
+ xcb_window_t win;
+ xcb_colormap_t cmap
+
+ /* Open the connection to the X server and get the first screen */
+ c = xcb_connect (NULL, NULL);
+ screen = xcb_setup_roots_iterator (xcb_get_setup (c)).data;
+
+ /* We create the window win here*/
+
+ cmap = xcb_generate_id (c);
+ xcb_create_colormap (c, XCB_COLORMAP_ALLOC_NONE, cmap, win, screen-&gt;root_visual);
+
+ return 0;
+}
+</pre>
+ <p>
+ Note that the window parameter is only used to allow the X
+ server to create the color map for the given screen. We can
+ then use this color map for any window drawn on the same screen.
+ </p>
+ <p>
+ To free a color map, it suffices to use this function:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_free_colormap (xcb_connection_t *c, /* The connection */
+ xcb_colormap_t cmap); /* The color map */
+</pre>
+ <div class="comp">
+ <div class="title">
+ Comparison Xlib/XCB
+ </div>
+ <div class="xlib">
+ <ul>
+ <li>XCreateColormap ()
+ </ul>
+ </div>
+ <div class="xcb">
+ <ul>
+ <li>xcb_generate_id ()
+ <li>xcb_create_colormap ()
+ </ul>
+ </div>
+ <div class="xlib">
+ <ul>
+ <li>XFreeColormap ()
+ </ul>
+ </div>
+ <div class="xcb">
+ <ul>
+ <li>xcb_free_colormap ()
+ </ul>
+ </div>
+ </div>
+ <br>
+ <li class="subtitle"><a name="alloccolor">Allocating and freeing a color entry</a>
+ <p>
+ Once we got access to some color map, we can start allocating
+ colors. The informations related to a color are stored in the
+ following structure:
+ </p>
+ <pre class="code">
+typedef struct {
+ uint8_t response_type;
+ uint8_t pad0;
+ uint16_t sequence;
+ uint32_t length;
+ uint16_t red; /* The red component */
+ uint16_t green; /* The green component */
+ uint16_t blue; /* The blue component */
+ uint8_t pad1[2];
+ uint32_t pixel; /* The entry in the color map, supplied by the X server */
+} xcb_alloc_color_reply_t;
+</pre>
+ <p>
+ XCB supplies these two functions to fill it:
+ </p>
+ <pre class="code">
+xcb_alloc_color_cookie_t xcb_alloc_color (xcb_connection_t *c,
+ xcb_colormap_t cmap,
+ uint16_t red,
+ uint16_t green,
+ uint16_t blue);
+xcb_alloc_color_reply_t *xcb_alloc_color_reply (xcb_connection_t *c,
+ xcb_alloc_color_cookie_t cookie,
+ xcb_generic_error_t **e);
+</pre>
+ <p>
+ The fuction <span class="code">xcb_alloc_color()</span> takes the
+ 3 RGB components as parameters (red, green and blue). Here is an
+ example of using these functions:
+ </p>
+ <pre class="code">
+#include &lt;malloc.h&gt;
+
+#include &lt;xcb/xcb.h&gt;
+
+int
+main ()
+{
+ xcb_connection_t *c;
+ xcb_screen_t *screen;
+ xcb_window_t win;
+ xcb_colormap_t cmap;
+ xcb_alloc_color_reply_t *rep;
+
+ /* Open the connection to the X server and get the first screen */
+ c = xcb_connect (NULL, NULL);
+ screen = xcb_setup_roots_iterator (xcb_get_setup (c)).data;
+
+ /* We create the window win here*/
+
+ cmap = xcb_generate_id (c);
+ xcb_create_colormap (c, XCB_COLORMAP_ALLOC_NONE, cmap, win, screen-&gt;root_visual);
+
+ rep = xcb_alloc_color_reply (c, xcb_alloc_color (c, cmap, 65535, 0, 0), NULL);
+
+ if (!rep)
+ return 0;
+
+ /* Do something with r-&gt;pixel or the components */
+
+ free (rep);
+
+ return 0;
+}
+</pre>
+ <p>
+ As <span class="code">xcb_alloc_color_reply()</span> allocates
+ memory, you have to free <span class="code">rep</span>.
+ </p>
+ <p>
+ <b>TODO</b>: Talk about freeing colors.
+ </p>
+ </ol>
+ <li class="title"><a name="pixmaps">X Bitmaps and Pixmaps</a>
+ <p>
+ One thing many so-called "Multi-Media" applications need to do,
+ is display images. In the X world, this is done using bitmaps
+ and pixmaps. We have already seen some usage of them when
+ setting an icon for our application. Lets study them further,
+ and see how to draw these images inside a window, along side the
+ simple graphics and text we have seen so far.
+ </p>
+ <p>
+ One thing to note before delving further, is that XCB (nor Xlib)
+ supplies no means of manipulating popular image formats, such as
+ gif, png, jpeg or tiff. It is up to the programmer (or to higher
+ level graphics libraries) to translate these image formats into
+ formats that the X server is familiar with (x bitmaps and x
+ pixmaps).
+ </p>
+ <ol>
+ <li class="subtitle"><a name="pixmapswhat">What is a X Bitmap? An X Pixmap?</a>
+ <p>
+ An X bitmap is a two-color image stored in a format specific
+ to the X window system. When stored in a file, the bitmap data
+ looks like a C source file. It contains variables defining the
+ width and the height of the bitmap, an array containing the
+ bit values of the bitmap (the size of the array is
+ (width+7)/8*height and the bit and byte order are LSB), and
+ an optional hot-spot location (that will
+ be explained later, when discussing mouse cursors).
+ </p>
+ <p>
+ An X pixmap is a format used to stored images in the memory of
+ an X server. This format can store both black and white images
+ (such as x bitmaps) as well as color images. It is the only
+ image format supported by the X protocol, and any image to be
+ drawn on screen, should be first translated into this format.
+ </p>
+ <p>
+ In actuality, an X pixmap can be thought of as a window that
+ does not appear on the screen. Many graphics operations that
+ work on windows, will also work on pixmaps. Indeed, the type
+ of X pixmap in XCB is an Id like a window:
+ </p>
+ <pre class="code">
+typedef uint32_t xcb_pixmap_t;
+</pre>
+ <p>
+ Like Xlib, there is no difference between a Drawable, a Window
+ or a Pixmap:
+ </p>
+ <pre class="code">
+typedef uint32_t xcb_drawable_t;
+</pre>
+ <p>
+ in order to avoid confusion between a window and a pixmap. The
+ operations that will work the same on a window or a pixmap
+ will require a <span class="code">xcb_drawable_t</span>
+ </p>
+ <div class="emph">
+ <p>
+ Remark: In Xlib, there is no specific difference between a
+ <span class="code">Drawable</span>, a
+ <span class="code">Pixmap</span> or a
+ <span class="code">Window</span>: all are 32 bit long
+ integer. XCB wraps all these different IDs in structures to
+ provide some measure of type-safety.
+ </p>
+ </div>
+ <li class="subtitle"><a name="pixmapscreate">Creating a pixmap</a>
+ <p>
+ Sometimes we want to create an un-initialized pixmap, so we
+ can later draw into it. This is useful for image drawing
+ programs (creating a new empty canvas will cause the creation
+ of a new pixmap on which the drawing can be stored). It is
+ also useful when reading various image formats: we load the
+ image data into memory, create a pixmap on the server, and
+ then draw the decoded image data onto that pixmap.
+ </p>
+ <p>
+ To create a new pixmap, we first ask the X server to give an
+ Id to our pixmap, with this function:
+ </p>
+ <pre class="code">
+xcb_pixmap_t xcb_generate_id (xcb_connection_t *c);
+</pre>
+ <p>
+ Then, XCB supplies the following function to create new pixmaps:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_create_pixmap (xcb_connection_t *c, /* Pointer to the xcb_connection_t structure */
+ uint8_t depth, /* Depth of the screen */
+ xcb_pixmap_t pid, /* Id of the pixmap */
+ xcb_drawable_t drawable,
+ uint16_t width, /* Width of the window (in pixels) */
+ uint16_t height); /* Height of the window (in pixels) */
+</pre>
+ <p>
+ <b>TODO</b>: Explain the drawable parameter, and give an
+ example (like <a href="xpoints.c">xpoints.c</a>)
+ </p>
+ <li class="subtitle"><a name="pixmapsdraw"></a>Drawing a pixmap in a window
+ <p>
+ Once we got a handle to a pixmap, we can draw it on some
+ window, using the following function:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_copy_area (xcb_connection_t *c, /* Pointer to the xcb_connection_t structure */
+ xcb_drawable_t src_drawable, /* The Drawable we want to paste */
+ xcb_drawable_t dst_drawable, /* The Drawable on which we copy the previous Drawable */
+ xcb_gcontext_t gc, /* A Graphic Context */
+ int16_t src_x, /* Top left x coordinate of the region we want to copy */
+ int16_t src_y, /* Top left y coordinate of the region we want to copy */
+ int16_t dst_x, /* Top left x coordinate of the region where we want to copy */
+ int16_t dst_y, /* Top left y coordinate of the region where we want to copy */
+ uint16_t width, /* Width of the region we want to copy */
+ uint16_t height); /* Height of the region we want to copy */
+</pre>
+ <p>
+ As you can see, we could copy the whole pixmap, as well as
+ only a given rectangle of the pixmap. This is useful to
+ optimize the drawing speed: we could copy only what we have
+ modified in the pixmap.
+ </p>
+ <p>
+ <b>One important note should be made</b>: it is possible to
+ create pixmaps with different depths on the same screen. When
+ we perform copy operations (a pixmap onto a window, etc), we
+ should make sure that both source and target have the same
+ depth. If they have a different depth, the operation would
+ fail. The exception to this is if we copy a specific bit plane
+ of the source pixmap using the
+ <span class="code">xcb_copy_plane_t</span> function. In such an
+ event, we can copy a specific plane to the target window (in
+ actuality, setting a specific bit in the color of each pixel
+ copied). This can be used to generate strange graphic effects
+ in a window, but that is beyond the scope of this tutorial.
+ </p>
+ <li class="subtitle"><a name="pixmapsfree"></a>Freeing a pixmap
+ <p>
+ Finally, when we are done using a given pixmap, we should free
+ it, in order to free resources of the X server. This is done
+ using this function:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_free_pixmap (xcb_connection_t *c, /* Pointer to the xcb_connection_t structure */
+ xcb_pixmap_t pixmap); /* A given pixmap */
+</pre>
+ <p>
+ Of course, after having freed it, we must not try accessing
+ the pixmap again.
+ </p>
+ <p>
+ <b>TODO</b>: Give an example, or a link to xpoints.c
+ </p>
+ </ol>
+ <li class="title"><a name="mousecursor">Messing with the mouse cursor</a>
+ <p>
+ It it possible to modify the shape of the mouse pointer (also
+ called the X pointer) when in certain states, as we otfen see in
+ programs. For example, a busy application would often display
+ the sand clock over its main window, to give the user a visual
+ hint that he should wait. Let's see how we can change the mouse
+ cursor of our windows.
+ </p>
+ <ol>
+ <li class="subtitle"><a name="mousecursorcreate">Creating and destroying a mouse cursor</a>
+ <p>
+ There are two methods for creating cursors. One of them is by
+ using a set of predefined cursors, that are supplied by the X
+ server, the other is by using a user-supplied bitmap.
+ </p>
+ <p>
+ In the first method, we use a special font named "cursor", and
+ the function <span class="code">xcb_create_glyph_cursor</span>:
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_create_glyph_cursor (xcb_connection_t *c,
+ xcb_cursor_t cid,
+ xcb_font_t source_font, /* font for the source glyph */
+ xcb_font_t mask_font, /* font for the mask glyph or XCB_NONE */
+ uint16_t source_char, /* character glyph for the source */
+ uint16_t mask_char, /* character glyph for the mask */
+ uint16_t fore_red, /* red value for the foreground of the source */
+ uint16_t fore_green, /* green value for the foreground of the source */
+ uint16_t fore_blue, /* blue value for the foreground of the source */
+ uint16_t back_red, /* red value for the background of the source */
+ uint16_t back_green, /* green value for the background of the source */
+ uint16_t back_blue) /* blue value for the background of the source */
+</pre>
+ <p>
+ <b>TODO</b>: Describe <span class="code">source_char</span>
+ and <span class="code">mask_char</span>, for example by giving
+ an example on how to get the values. There is a list there:
+ <a href="http://tronche.com/gui/x/xlib/appendix/b/">X Font Cursors</a>
+ </p>
+ <p>
+ So we first open that font (see <a href="#loadfont">Loading a Font</a>)
+ and create the new cursor. As for every X ressource, we have to
+ ask for an X id with <span class="code">xcb_generate_id</span>
+ first:
+ </p>
+ <pre class="code">
+xcb_font_t font;
+xcb_cursor_t cursor;
+
+/* The connection is set */
+
+font = xcb_generate_id (conn);
+xcb_open_font (conn, font, strlen ("cursor"), "cursor");
+
+cursor = xcb_generate_id (conn);
+xcb_create_glyph_cursor (conn, cursor, font, font,
+ 58, 58 + 1,
+ 0, 0, 0,
+ 0, 0, 0);
+</pre>
+ <p>
+ We have created the cursor "right hand" by specifying 58 to
+ the <span class="code">source_fon</span>t argument and 58 + 1
+ to the <span class="code">mask_font</span>.
+ </p>
+ <p>
+ The cursor is destroyed by using the function
+ </p>
+ <pre class="code">
+xcb_void_cookie_t xcb_free_cursor (xcb_connection_t *c,
+ xcb_cursor_t cursor);
+</pre>
+ <p>
+ In the second method, we create a new cursor by using a pair
+ of pixmaps, with depth of one (that is, two colors
+ pixmaps). One pixmap defines the shape of the cursor, while
+ the other works as a mask, specifying which pixels of the
+ cursor will be actually drawn. The rest of the pixels will be
+ transparent.
+ </p>
+ <p>
+ <b>TODO</b>: give an example.
+ </p>
+ <li class="subtitle"><a name="mousecursorset">Setting a window's mouse cursor</a>
+ <p>
+ Once the cursor is created, we can modify the cursor of our
+ window by using <span class="code">xcb_change_window_attributes</span>
+ and using the <span class="code">XCB_CWCURSOR</span> attribute:
+ </p>
+ <pre class="code">
+uint32_t mask;
+uint32_t value_list;
+
+/* The connection and window are set */
+/* The cursor is already created */
+
+mask = XCB_CWCURSOR;
+value_list = cursor;
+xcb_change_window_attributes (conn, window, mask, &amp;value_list);
+</pre>
+ <p>
+ Of course, the cursor and the font must be freed.
+ </p>
+ <li class="subtitle"><a name="mousecursorexample">Complete example</a>
+ <p>
+ The following example displays a window with a
+ button. When entering the window, the window cursor is changed
+ to an arrow. When clicking once on the button, the cursor is
+ changed to a hand. When clicking again on the button, the
+ cursor window gets back to the arrow. The Esc key exits the
+ application.
+ </p>
+ <pre class="code">
+#include &lt;stdlib.h&gt;
+#include &lt;stdio.h&gt;
+#include &lt;string.h&gt;
+
+#include &lt;xcb/xcb.h&gt;
+
+#define WIDTH 300
+#define HEIGHT 150
+
+
+
+static xcb_gc_t gc_font_get (xcb_connection_t *c,
+ xcb_screen_t *screen,
+ xcb_window_t window,
+ const char *font_name);
+
+static void button_draw (xcb_connection_t *c,
+ xcb_screen_t *screen,
+ xcb_window_t window,
+ int16_t x1,
+ int16_t y1,
+ const char *label);
+
+static void text_draw (xcb_connection_t *c,
+ xcb_screen_t *screen,
+ xcb_window_t window,
+ int16_t x1,
+ int16_t y1,
+ const char *label);
+
+static void cursor_set (xcb_connection_t *c,
+ xcb_screen_t *screen,
+ xcb_window_t window,
+ int cursor_id);
+
+
+static void
+button_draw (xcb_connection_t *c,
+ xcb_screen_t *screen,
+ xcb_window_t window,
+ int16_t x1,
+ int16_t y1,
+ const char *label)
+{
+ xcb_point_t points[5];
+ xcb_void_cookie_t cookie_gc;
+ xcb_void_cookie_t cookie_line;
+ xcb_void_cookie_t cookie_text;
+ xcb_generic_error_t *error;
+ xcb_gcontext_t gc;
+ int16_t width;
+ int16_t height;
+ uint8_t length;
+ int16_t inset;
+
+ length = strlen (label);
+ inset = 2;
+
+ gc = gc_font_get(c, screen, window, "7x13");
+
+ width = 7 * length + 2 * (inset + 1);
+ height = 13 + 2 * (inset + 1);
+ points[0].x = x1;
+ points[0].y = y1;
+ points[1].x = x1 + width;
+ points[1].y = y1;
+ points[2].x = x1 + width;
+ points[2].y = y1 - height;
+ points[3].x = x1;
+ points[3].y = y1 - height;
+ points[4].x = x1;
+ points[4].y = y1;
+ cookie_line = xcb_poly_line_checked (c, XCB_COORD_MODE_ORIGIN,
+ window, gc, 5, points);
+
+ error = xcb_request_check (c, cookie_line);
+ if (error) {
+ fprintf (stderr, "ERROR: can't draw lines : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+
+ cookie_text = xcb_image_text_8_checked (c, length, window, gc,
+ x1 + inset + 1,
+ y1 - inset - 1, label);
+ error = xcb_request_check (c, cookie_text);
+ if (error) {
+ fprintf (stderr, "ERROR: can't paste text : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+
+ cookie_gc = xcb_free_gc (c, gc);
+ error = xcb_request_check (c, cookie_gc);
+ if (error) {
+ fprintf (stderr, "ERROR: can't free gc : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+}
+
+static void
+text_draw (xcb_connection_t *c,
+ xcb_screen_t *screen,
+ xcb_window_t window,
+ int16_t x1,
+ int16_t y1,
+ const char *label)
+{
+ xcb_void_cookie_t cookie_gc;
+ xcb_void_cookie_t cookie_text;
+ xcb_generic_error_t *error;
+ xcb_gcontext_t gc;
+ uint8_t length;
+
+ length = strlen (label);
+
+ gc = gc_font_get(c, screen, window, "7x13");
+
+ cookie_text = xcb_image_text_8_checked (c, length, window, gc,
+ x1,
+ y1, label);
+ error = xcb_request_check (c, cookie_text);
+ if (error) {
+ fprintf (stderr, "ERROR: can't paste text : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+
+ cookie_gc = xcb_free_gc (c, gc);
+ error = xcb_request_check (c, cookie_gc);
+ if (error) {
+ fprintf (stderr, "ERROR: can't free gc : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+}
+
+static xcb_gc_t
+gc_font_get (xcb_connection_t *c,
+ xcb_screen_t *screen,
+ xcb_window_t window,
+ const char *font_name)
+{
+ uint32_t value_list[3];
+ xcb_void_cookie_t cookie_font;
+ xcb_void_cookie_t cookie_gc;
+ xcb_generic_error_t *error;
+ xcb_font_t font;
+ xcb_gcontext_t gc;
+ uint32_t mask;
+
+ font = xcb_generate_id (c);
+ cookie_font = xcb_open_font_checked (c, font,
+ strlen (font_name),
+ font_name);
+
+ error = xcb_request_check (c, cookie_font);
+ if (error) {
+ fprintf (stderr, "ERROR: can't open font : %d\n", error->error_code);
+ xcb_disconnect (c);
+ return -1;
+ }
+
+ gc = xcb_generate_id (c);
+ mask = XCB_GC_FOREGROUND | XCB_GC_BACKGROUND | XCB_GC_FONT;
+ value_list[0] = screen->black_pixel;
+ value_list[1] = screen->white_pixel;
+ value_list[2] = font;
+ cookie_gc = xcb_create_gc_checked (c, gc, window, mask, value_list);
+ error = xcb_request_check (c, cookie_gc);
+ if (error) {
+ fprintf (stderr, "ERROR: can't create gc : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+
+ cookie_font = xcb_close_font_checked (c, font);
+ error = xcb_request_check (c, cookie_font);
+ if (error) {
+ fprintf (stderr, "ERROR: can't close font : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+
+ return gc;
+}
+
+static void
+cursor_set (xcb_connection_t *c,
+ xcb_screen_t *screen,
+ xcb_window_t window,
+ int cursor_id)
+{
+ uint32_t values_list[3];
+ xcb_void_cookie_t cookie_font;
+ xcb_void_cookie_t cookie_gc;
+ xcb_generic_error_t *error;
+ xcb_font_t font;
+ xcb_cursor_t cursor;
+ xcb_gcontext_t gc;
+ uint32_t mask;
+ uint32_t value_list;
+
+ font = xcb_generate_id (c);
+ cookie_font = xcb_open_font_checked (c, font,
+ strlen ("cursor"),
+ "cursor");
+ error = xcb_request_check (c, cookie_font);
+ if (error) {
+ fprintf (stderr, "ERROR: can't open font : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+
+ cursor = xcb_generate_id (c);
+ xcb_create_glyph_cursor (c, cursor, font, font,
+ cursor_id, cursor_id + 1,
+ 0, 0, 0,
+ 0, 0, 0);
+
+ gc = xcb_generate_id (c);
+ mask = XCB_GC_FOREGROUND | XCB_GC_BACKGROUND | XCB_GC_FONT;
+ values_list[0] = screen->black_pixel;
+ values_list[1] = screen->white_pixel;
+ values_list[2] = font;
+ cookie_gc = xcb_create_gc_checked (c, gc, window, mask, values_list);
+ error = xcb_request_check (c, cookie_gc);
+ if (error) {
+ fprintf (stderr, "ERROR: can't create gc : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+
+ mask = XCB_CW_CURSOR;
+ value_list = cursor;
+ xcb_change_window_attributes (c, window, mask, &amp;value_list);
+
+ xcb_free_cursor (c, cursor);
+
+ cookie_font = xcb_close_font_checked (c, font);
+ error = xcb_request_check (c, cookie_font);
+ if (error) {
+ fprintf (stderr, "ERROR: can't close font : %d\n", error->error_code);
+ xcb_disconnect (c);
+ exit (-1);
+ }
+}
+
+int main ()
+{
+ xcb_screen_iterator_t screen_iter;
+ xcb_connection_t *c;
+ const xcb_setup_t *setup;
+ xcb_screen_t *screen;
+ xcb_generic_event_t *e;
+ xcb_generic_error_t *error;
+ xcb_void_cookie_t cookie_window;
+ xcb_void_cookie_t cookie_map;
+ xcb_window_t window;
+ uint32_t mask;
+ uint32_t values[2];
+ int screen_number;
+ uint8_t is_hand = 0;
+
+ /* getting the connection */
+ c = xcb_connect (NULL, &amp;screen_number);
+ if (!c) {
+ fprintf (stderr, "ERROR: can't connect to an X server\n");
+ return -1;
+ }
+
+ /* getting the current screen */
+ setup = xcb_get_setup (c);
+
+ screen = NULL;
+ screen_iter = xcb_setup_roots_iterator (setup);
+ for (; screen_iter.rem != 0; --screen_number, xcb_screen_next (&amp;screen_iter))
+ if (screen_number == 0)
+ {
+ screen = screen_iter.data;
+ break;
+ }
+ if (!screen) {
+ fprintf (stderr, "ERROR: can't get the current screen\n");
+ xcb_disconnect (c);
+ return -1;
+ }
+
+ /* creating the window */
+ window = xcb_generate_id (c);
+ mask = XCB_CW_BACK_PIXEL | XCB_CW_EVENT_MASK;
+ values[0] = screen->white_pixel;
+ values[1] =
+ XCB_EVENT_MASK_KEY_RELEASE |
+ XCB_EVENT_MASK_BUTTON_PRESS |
+ XCB_EVENT_MASK_EXPOSURE |
+ XCB_EVENT_MASK_POINTER_MOTION;
+ cookie_window = xcb_create_window_checked (c,
+ screen->root_depth,
+ window, screen->root,
+ 20, 200, WIDTH, HEIGHT,
+ 0, XCB_WINDOW_CLASS_INPUT_OUTPUT,
+ screen->root_visual,
+ mask, values);
+ cookie_map = xcb_map_window_checked (c, window);
+
+ /* error managing */
+ error = xcb_request_check (c, cookie_window);
+ if (error) {
+ fprintf (stderr, "ERROR: can't create window : %d\n", error->error_code);
+ xcb_disconnect (c);
+ return -1;
+ }
+ error = xcb_request_check (c, cookie_map);
+ if (error) {
+ fprintf (stderr, "ERROR: can't map window : %d\n", error->error_code);
+ xcb_disconnect (c);
+ return -1;
+ }
+
+ cursor_set (c, screen, window, 68);
+
+ xcb_flush(c);
+
+ while (1) {
+ e = xcb_poll_for_event(c);
+ if (e) {
+ switch (e->response_type &amp; ~0x80) {
+ case XCB_EXPOSE: {
+ char *text;
+
+ text = "click here to change cursor";
+ button_draw (c, screen, window,
+ (WIDTH - 7 * strlen(text)) / 2,
+ (HEIGHT - 16) / 2, text);
+
+ text = "Press ESC key to exit...";
+ text_draw (c, screen, window, 10, HEIGHT - 10, text);
+ break;
+ }
+ case XCB_BUTTON_PRESS: {
+ xcb_button_press_event_t *ev;
+ int length;
+
+ ev = (xcb_button_press_event_t *)e;
+ length = strlen ("click here to change cursor");
+
+ if ((ev->event_x &gt;= (WIDTH - 7 * length) / 2) &amp;&amp;
+ (ev->event_x &lt;= ((WIDTH - 7 * length) / 2 + 7 * length + 6)) &amp;&amp;
+ (ev->event_y &gt;= (HEIGHT - 16) / 2 - 19) &amp;&amp;
+ (ev->event_y &lt;= ((HEIGHT - 16) / 2)))
+ is_hand = 1 - is_hand;
+
+ is_hand ? cursor_set (c, screen, window, 58) : cursor_set (c, screen, window, 68);
+ }
+ case XCB_KEY_RELEASE: {
+ xcb_key_release_event_t *ev;
+
+ ev = (xcb_key_release_event_t *)e;
+
+ switch (ev->detail) {
+ /* ESC */
+ case 9:
+ free (e);
+ xcb_disconnect (c);
+ return 0;
+ }
+ }
+ }
+ free (e);
+ }
+ }
+
+ return 0;
+}
+</pre>
+ </ol>
+ <li class="title"><a name="translation">Translation of basic Xlib functions and macros</a>
+ <p>
+ The problem when you want to port an Xlib program to XCB is that
+ you don't know if the Xlib function that you want to "translate"
+ is a X Window one or an Xlib macro. In that section, we describe
+ a way to translate the usual functions or macros that Xlib
+ provides. It's usually just a member of a structure.
+ </p>
+ <ol>
+ <li class="subtitle"><a name="displaystructure">Members of the Display structure</a>
+ <p>
+ In this section, we look at how to translate the macros that
+ return some members of the <span class="code">Display</span>
+ structure. They are obtained by using a function that requires a
+ <span class="code">xcb_connection_t *</span> or a member of the
+ <span class="code">xcb_setup_t</span> structure
+ (via the function <span class="code">xcb_get_setup</span>), or
+ a function that requires that structure.
+ </p>
+ <ol>
+ <li class="subtitle"><a name="ConnectionNumber">ConnectionNumber</a>
+ <p>
+ This number is the file descriptor that connects the client
+ to the server. You just have to use that function:
+ </p>
+ <pre class="code">
+int xcb_get_file_descriptor (xcb_connection_t *c);
+</pre>
+ <li class="subtitle"><a name="DefaultScreen"></a>DefaultScreen
+ <p>
+ That number is not stored by XCB. It is returned in the
+ second parameter of the function <span class="code"><a href="#openconn">xcb_connect</a></span>.
+ Hence, you have to store it yourself if you want to use
+ it. Then, to get the <span class="code">xcb_screen_t</span>
+ structure, you have to iterate on the screens.
+ The equivalent function of the Xlib's
+ <span class="code">ScreenOfDisplay</span> function can be
+ found <a href="#ScreenOfDisplay">below</a>. This is also provided in the
+ xcb_aux_t library as <span class="code">xcb_aux_get_screen()</span>. OK, here is the
+ small piece of code to get that number:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+int screen_default_nbr;
+
+/* you pass the name of the display you want to xcb_connect_t */
+
+c = xcb_connect (display_name, &amp;screen_default_nbr);
+
+/* screen_default_nbr contains now the number of the default screen */
+</pre>
+ <li class="subtitle"><a name="QLength"></a>QLength
+ <p>
+ Not documented yet.
+ </p>
+ <p>
+ However, this points out a basic difference in philosophy between
+ Xlib and XCB. Xlib has several functions for filtering and
+ manipulating the incoming and outgoing X message queues. XCB
+ wishes to hide this as much as possible from the user, which
+ allows for more freedom in implementation strategies.
+ </p>
+ <li class="subtitle"><a name="ScreenCount"></a>ScreenCount
+ <p>
+ You get the count of screens with the functions
+ <span class="code">xcb_get_setup</span>
+ and
+ <span class="code">xcb_setup_roots_iterator</span>
+ (if you need to iterate):
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+int screen_count;
+
+/* you init the connection */
+
+screen_count = xcb_setup_roots_iterator (xcb_get_setup (c)).rem;
+
+/* screen_count contains now the count of screens */
+</pre>
+ <p>
+ If you don't want to iterate over the screens, a better way
+ to get that number is to use
+ <span class="code">xcb_setup_roots_length_t</span>:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+int screen_count;
+
+/* you init the connection */
+
+screen_count = xcb_setup_roots_length (xcb_get_setup (c));
+
+/* screen_count contains now the count of screens */
+</pre>
+ <li class="subtitle"><a name="ServerVendor"></a>ServerVendor
+ <p>
+ You get the name of the vendor of the server hardware with
+ the functions <span class="code">xcb_get_setup</span>
+ and
+ <span
+ class="code">xcb_setup_vendor</span>. Beware
+ that, unlike Xlib, the string returned by XCB is not
+ necessarily null-terminaled:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+char *vendor = NULL;
+int length;
+
+/* you init the connection */
+length = xcb_setup_vendor_length (xcb_get_setup (c));
+vendor = (char *)malloc (length + 1);
+if (vendor)
+memcpy (vendor, xcb_setup_vendor (xcb_get_setup (c)), length);
+vendor[length] = '\0';
+
+/* vendor contains now the name of the vendor. Must be freed when not used anymore */
+</pre>
+ <li class="subtitle"><a name="ProtocolVersion"></a>ProtocolVersion
+ <p>
+ You get the major version of the protocol in the
+ <span class="code">xcb_setup_t</span>
+ structure, with the function <span class="code">xcb_get_setup</span>:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+uint16_t protocol_major_version;
+
+/* you init the connection */
+
+protocol_major_version = xcb_get_setup (c)-&gt;protocol_major_version;
+
+/* protocol_major_version contains now the major version of the protocol */
+</pre>
+ <li class="subtitle"><a name="ProtocolRevision"></a>ProtocolRevision
+ <p>
+ You get the minor version of the protocol in the
+ <span class="code">xcb_setup_t</span>
+ structure, with the function <span class="code">xcb_get_setup</span>:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+uint16_t protocol_minor_version;
+
+/* you init the connection */
+
+protocol_minor_version = xcb_get_setup (c)-&gt;protocol_minor_version;
+
+/* protocol_minor_version contains now the minor version of the protocol */
+</pre>
+ <li class="subtitle"><a name="VendorRelease"></a>VendorRelease
+ <p>
+ You get the number of the release of the server hardware in the
+ <span class="code">xcb_setup_t</span>
+ structure, with the function <span class="code">xcb_get_setup</span>:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+uint32_t release_number;
+
+/* you init the connection */
+
+release_number = xcb_get_setup (c)-&gt;release_number;
+
+/* release_number contains now the number of the release of the server hardware */
+</pre>
+ <li class="subtitle"><a name="DisplayString"></a>DisplayString
+ <p>
+ The name of the display is not stored in XCB. You have to
+ store it by yourself.
+ </p>
+ <li class="subtitle"><a name="BitmapUnit"></a>BitmapUnit
+ <p>
+ You get the bitmap scanline unit in the
+ <span class="code">xcb_setup_t</span>
+ structure, with the function <span class="code">xcb_get_setup</span>:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+uint8_t bitmap_format_scanline_unit;
+
+/* you init the connection */
+
+bitmap_format_scanline_unit = xcb_get_setup (c)-&gt;bitmap_format_scanline_unit;
+
+/* bitmap_format_scanline_unit contains now the bitmap scanline unit */
+</pre>
+ <li class="subtitle"><a name="BitmapBitOrder"></a>BitmapBitOrder
+ <p>
+ You get the bitmap bit order in the
+ <span class="code">xcb_setup_t</span>
+ structure, with the function <span class="code">xcb_get_setup</span>:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+uint8_t bitmap_format_bit_order;
+
+/* you init the connection */
+
+bitmap_format_bit_order = xcb_get_setup (c)-&gt;bitmap_format_bit_order;
+
+/* bitmap_format_bit_order contains now the bitmap bit order */
+</pre>
+ <li class="subtitle"><a name="BitmapPad"></a>BitmapPad
+ <p>
+ You get the bitmap scanline pad in the
+ <span class="code">xcb_setup_t</span>
+ structure, with the function <span class="code">xcb_get_setup</span>:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+uint8_t bitmap_format_scanline_pad;
+
+/* you init the connection */
+
+bitmap_format_scanline_pad = xcb_get_setup (c)-&gt;bitmap_format_scanline_pad;
+
+/* bitmap_format_scanline_pad contains now the bitmap scanline pad */
+</pre>
+ <li class="subtitle"><a name="ImageByteOrder"></a>ImageByteOrder
+ <p>
+ You get the image byte order in the
+ <span class="code">xcb_setup_t</span>
+ structure, with the function <span class="code">xcb_get_setup</span>:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+uint8_t image_byte_order;
+
+/* you init the connection */
+
+image_byte_order = xcb_get_setup (c)-&gt;image_byte_order;
+
+/* image_byte_order contains now the image byte order */
+</pre>
+ </ol>
+ <li class="subtitle"><a name="screenofdisplay">ScreenOfDisplay related functions</a>
+ <p>
+ in Xlib, <span class="code">ScreenOfDisplay</span> returns a
+ <span class="code">Screen</span> structure that contains
+ several characteristics of your screen. XCB has a similar
+ structure (<span class="code">xcb_screen_t</span>),
+ but the way to obtain it is a bit different. With
+ Xlib, you just provide the number of the screen and you grab it
+ from an array. With XCB, you iterate over all the screens to
+ obtain the one you want. The complexity of this operation is
+ O(n). So the best is to store this structure if you use
+ it often. See <a href="#ScreenOfDisplay">screen_of_display</a> just below.
+ </p>
+ <p>
+ Xlib provides generally two functions to obtain the characteristics
+ related to the screen. One with the display and the number of
+ the screen, which calls <span class="code">ScreenOfDisplay</span>,
+ and the other that uses the <span class="code">Screen</span> structure.
+ This might be a bit confusing. As mentioned above, with XCB, it
+ is better to store the <span class="code">xcb_screen_t</span>
+ structure. Then, you have to read the members of this
+ structure. That's why the Xlib functions are put by pairs (or
+ more) as, with XCB, you will use the same code.
+ </p>
+ <ol>
+ <li class="subtitle"><a name="ScreenOfDisplay">ScreenOfDisplay</a>
+ <p>
+ This function returns the Xlib <span class="code">Screen</span>
+ structure. With XCB, you iterate over all the screens and
+ once you get the one you want, you return it:
+ </p>
+ <pre class="code"><a name="ScreenOfDisplay"></a>
+xcb_screen_t *screen_of_display (xcb_connection_t *c,
+ int screen)
+{
+ xcb_screen_iterator_t iter;
+
+ iter = xcb_setup_roots_iterator (xcb_get_setup (c));
+ for (; iter.rem; --screen, xcb_screen_next (&amp;iter))
+ if (screen == 0)
+ return iter.data;
+
+ return NULL;
+}
+</pre>
+ <p>
+ As mentioned above, you might want to store the value
+ returned by this function.
+ </p>
+ <p>
+ All the functions below will use the result of that
+ function, as they just grab a specific member of the
+ <span class="code">xcb_screen_t</span> structure.
+ </p>
+ <li class="subtitle"><a name="DefaultScreenOfDisplay"></a>DefaultScreenOfDisplay
+ <p>
+ It is the default screen that you obtain when you connect to
+ the X server. It suffices to call the <a href="#ScreenOfDisplay">screen_of_display</a>
+ function above with the connection and the number of the
+ default screen.
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+int screen_default_nbr;
+xcb_screen_t *default_screen; /* the returned default screen */
+
+/* you pass the name of the display you want to xcb_connect_t */
+
+c = xcb_connect (display_name, &amp;screen_default_nbr);
+default_screen = screen_of_display (c, screen_default_nbr);
+
+/* default_screen contains now the default root window, or a NULL window if no screen is found */
+</pre>
+ <li class="subtitle"><a name="RootWindow">RootWindow / RootWindowOfScreen</a>
+ <br>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+xcb_window_t root_window = { 0 }; /* the returned window */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ root_window = screen-&gt;root;
+
+/* root_window contains now the root window, or a NULL window if no screen is found */
+</pre>
+ <li class="subtitle"><a name="DefaultRootWindow">DefaultRootWindow</a>
+ <p>
+ It is the root window of the default screen. So, you call
+ <a name="ScreenOfDisplay">ScreenOfDisplay</a> with the
+ default screen number and you get the
+ <a href="#RootWindow">root window</a> as above:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_default_nbr;
+xcb_window_t root_window = { 0 }; /* the returned root window */
+
+/* you pass the name of the display you want to xcb_connect_t */
+
+c = xcb_connect (display_name, &amp;screen_default_nbr);
+screen = screen_of_display (c, screen_default_nbr);
+if (screen)
+ root_window = screen-&gt;root;
+
+/* root_window contains now the default root window, or a NULL window if no screen is found */
+</pre>
+ <li class="subtitle"><a name="DefaultVisual">DefaultVisual / DefaultVisualOfScreen</a>
+ <p>
+ While a Visual is, in Xlib, a structure, in XCB, there are
+ two types: <span class="code">xcb_visualid_t</span>, which is
+ the Id of the visual, and <span class="code">xcb_visualtype_t</span>,
+ which corresponds to the Xlib Visual. To get the Id of the
+ visual of a screen, just get the
+ <span class="code">root_visual</span>
+ member of a <span class="code">xcb_screen_t</span>:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+xcb_visualid_t root_visual = { 0 }; /* the returned visual Id */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ root_visual = screen-&gt;root_visual;
+
+/* root_visual contains now the value of the Id of the visual, or a NULL visual if no screen is found */
+</pre>
+ <p>
+ To get the <span class="code">xcb_visualtype_t</span>
+ structure, it's a bit less easy. You have to get the
+ <span class="code">xcb_screen_t</span> structure that you want,
+ get its <span class="code">root_visual</span> member,
+ then iterate over the <span class="code">xcb_depth_t</span>s
+ and the <span class="code">xcb_visualtype_t</span>s, and compare
+ the <span class="code">xcb_visualid_t</span> of these <span class="code">xcb_visualtype_t</span>s:
+ with <span class="code">root_visual</span>:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+xcb_visualid_t root_visual = { 0 };
+xcb_visualtype_t *visual_type = NULL; /* the returned visual type */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen) {
+ xcb_depth_iterator_t depth_iter;
+
+ depth_iter = xcb_screen_allowed_depths_iterator (screen);
+ for (; depth_iter.rem; xcb_depth_next (&amp;depth_iter)) {
+ xcb_visualtype_iterator_t visual_iter;
+
+ visual_iter = xcb_depth_visuals_iterator (depth_iter.data);
+ for (; visual_iter.rem; xcb_visualtype_next (&amp;visual_iter)) {
+ if (screen-&gt;root_visual == visual_iter.data-&gt;visual_id) {
+ visual_type = visual_iter.data;
+ break;
+ }
+ }
+ }
+}
+
+/* visual_type contains now the visual structure, or a NULL visual structure if no screen is found */
+</pre>
+ <li class="subtitle"><a name="DefaultGC">DefaultGC / DefaultGCOfScreen</a>
+ <p>
+ This default Graphic Context is just a newly created Graphic
+ Context, associated to the root window of a
+ <span class="code">xcb_screen_t</span>,
+ using the black white pixels of that screen:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+xcb_gcontext_t gc = { 0 }; /* the returned default graphic context */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen) {
+ xcb_drawable_t draw;
+ uint32_t mask;
+ uint32_t values[2];
+
+ gc = xcb_generate_id (c);
+ draw = screen-&gt;root;
+ mask = XCB_GC_FOREGROUND | XCB_GC_BACKGROUND;
+ values[0] = screen-&gt;black_pixel;
+ values[1] = screen-&gt;white_pixel;
+ xcb_create_gc (c, gc, draw, mask, values);
+}
+
+/* gc contains now the default graphic context */
+</pre>
+ <li class="subtitle"><a name="BlackPixel">BlackPixel / BlackPixelOfScreen</a>
+ <p>
+ It is the Id of the black pixel, which is in the structure
+ of an <span class="code">xcb_screen_t</span>.
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+uint32_t black_pixel = 0; /* the returned black pixel */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ black_pixel = screen-&gt;black_pixel;
+
+/* black_pixel contains now the value of the black pixel, or 0 if no screen is found */
+</pre>
+ <li class="subtitle"><a name="WhitePixel">WhitePixel / WhitePixelOfScreen</a>
+ <p>
+ It is the Id of the white pixel, which is in the structure
+ of an <span class="code">xcb_screen_t</span>.
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+uint32_t white_pixel = 0; /* the returned white pixel */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ white_pixel = screen-&gt;white_pixel;
+
+/* white_pixel contains now the value of the white pixel, or 0 if no screen is found */
+</pre>
+ <li class="subtitle"><a name="DisplayWidth">DisplayWidth / WidthOfScreen</a>
+ <p>
+ It is the width in pixels of the screen that you want, and
+ which is in the structure of the corresponding
+ <span class="code">xcb_screen_t</span>.
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+uint32_t width_in_pixels = 0; /* the returned width in pixels */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ width_in_pixels = screen-&gt;width_in_pixels;
+
+/* width_in_pixels contains now the width in pixels, or 0 if no screen is found */
+</pre>
+ <li class="subtitle"><a name="DisplayHeight">DisplayHeight / HeightOfScreen</a>
+ <p>
+ It is the height in pixels of the screen that you want, and
+ which is in the structure of the corresponding
+ <span class="code">xcb_screen_t</span>.
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+uint32_t height_in_pixels = 0; /* the returned height in pixels */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ height_in_pixels = screen-&gt;height_in_pixels;
+
+/* height_in_pixels contains now the height in pixels, or 0 if no screen is found */
+</pre>
+ <li class="subtitle"><a name="DisplayWidthMM">DisplayWidthMM / WidthMMOfScreen</a>
+ <p>
+ It is the width in millimeters of the screen that you want, and
+ which is in the structure of the corresponding
+ <span class="code">xcb_screen_t</span>.
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+uint32_t width_in_millimeters = 0; /* the returned width in millimeters */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ width_in_millimeters = screen-&gt;width_in_millimeters;
+
+/* width_in_millimeters contains now the width in millimeters, or 0 if no screen is found */
+</pre>
+ <li class="subtitle"><a name="DisplayHeightMM">DisplayHeightMM / HeightMMOfScreen</a>
+ <p>
+ It is the height in millimeters of the screen that you want, and
+ which is in the structure of the corresponding
+ <span class="code">xcb_screen_t</span>.
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+uint32_t height_in_millimeters = 0; /* the returned height in millimeters */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ height_in_millimeters = screen-&gt;height_in_millimeters;
+
+/* height_in_millimeters contains now the height in millimeters, or 0 if no screen is found */
+</pre>
+ <li class="subtitle"><a name="DisplayPlanes">DisplayPlanes / DefaultDepth / DefaultDepthOfScreen / PlanesOfScreen</a>
+ <p>
+ It is the depth (in bits) of the root window of the
+ screen. You get it from the <span class="code">xcb_screen_t</span> structure.
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+uint8_t root_depth = 0; /* the returned depth of the root window */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ root_depth = screen-&gt;root_depth;
+
+/* root_depth contains now the depth of the root window, or 0 if no screen is found */
+</pre>
+ <li class="subtitle"><a name="DefaultColormap">DefaultColormap / DefaultColormapOfScreen</a>
+ <p>
+ This is the default colormap of the screen (and not the
+ (default) colormap of the default screen !). As usual, you
+ get it from the <span class="code">xcb_screen_t</span> structure:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+xcb_colormap_t default_colormap = { 0 }; /* the returned default colormap */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ default_colormap = screen-&gt;default_colormap;
+
+/* default_colormap contains now the default colormap, or a NULL colormap if no screen is found */
+</pre>
+ <li class="subtitle"><a name="MinCmapsOfScreen"></a>MinCmapsOfScreen
+ <p>
+ You get the minimum installed colormaps in the <span class="code">xcb_screen_t</span> structure:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+uint16_t min_installed_maps = 0; /* the returned minimum installed colormaps */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ min_installed_maps = screen-&gt;min_installed_maps;
+
+/* min_installed_maps contains now the minimum installed colormaps, or 0 if no screen is found */
+</pre>
+ <li class="subtitle"><a name="MaxCmapsOfScreen"></a>MaxCmapsOfScreen
+ <p>
+ You get the maximum installed colormaps in the <span class="code">xcb_screen_t</span> structure:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+uint16_t max_installed_maps = 0; /* the returned maximum installed colormaps */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ max_installed_maps = screen-&gt;max_installed_maps;
+
+/* max_installed_maps contains now the maximum installed colormaps, or 0 if no screen is found */
+</pre>
+ <li class="subtitle"><a name="DoesSaveUnders"></a>DoesSaveUnders
+ <p>
+ You know if <span class="code">save_unders</span> is set,
+ by looking in the <span class="code">xcb_screen_t</span> structure:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+uint8_t save_unders = 0; /* the returned value of save_unders */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ save_unders = screen-&gt;save_unders;
+
+/* save_unders contains now the value of save_unders, or FALSE if no screen is found */
+</pre>
+ <li class="subtitle"><a name="DoesBackingStore"></a>DoesBackingStore
+ <p>
+ You know the value of <span class="code">backing_stores</span>,
+ by looking in the <span class="code">xcb_screen_t</span> structure:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+uint8_t backing_stores = 0; /* the returned value of backing_stores */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ backing_stores = screen-&gt;backing_stores;
+
+/* backing_stores contains now the value of backing_stores, or FALSE if no screen is found */
+</pre>
+ <li class="subtitle"><a name="EventMaskOfScreen"></a>EventMaskOfScreen
+ <p>
+ To get the current input masks,
+ you look in the <span class="code">xcb_screen_t</span> structure:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_screen_t *screen;
+int screen_nbr;
+uint32_t current_input_masks = 0; /* the returned value of current input masks */
+
+/* you init the connection and screen_nbr */
+
+screen = screen_of_display (c, screen_nbr);
+if (screen)
+ current_input_masks = screen-&gt;current_input_masks;
+
+/* current_input_masks contains now the value of the current input masks, or FALSE if no screen is found */
+</pre>
+ </ol>
+ <li class="subtitle"><a name="misc">Miscellaneous macros</a>
+ <ol>
+ <li class="subtitle"><a name="DisplayOfScreen"></a>DisplayOfScreen
+ <p>
+ in Xlib, the <span class="code">Screen</span> structure
+ stores its associated <span class="code">Display</span>
+ structure. This is not the case in the X Window protocol,
+ hence, it's also not the case in XCB. So you have to store
+ it by yourself.
+ </p>
+ <li class="subtitle"><a name="DisplayCells"></a>DisplayCells / CellsOfScreen
+ <p>
+ To get the colormap entries,
+ you look in the <span class="code">xcb_visualtype_t</span>
+ structure, that you grab like <a class="subsection" href="#DefaultVisual">here</a>:
+ </p>
+ <pre class="code">
+xcb_connection_t *c;
+xcb_visualtype_t *visual_type;
+uint16_t colormap_entries = 0; /* the returned value of the colormap entries */
+
+/* you init the connection and visual_type */
+
+if (visual_type)
+ colormap_entries = visual_type-&gt;colormap_entries;
+
+/* colormap_entries contains now the value of the colormap entries, or FALSE if no screen is found */
+</pre>
+ </ol>
+ </ol>
+ </ol>
+ </div>
+</body>
+
+</html>
diff --git a/libxcb/doc/tutorial/xcb.css b/libxcb/doc/tutorial/xcb.css
new file mode 100644
index 000000000..e059b3b33
--- /dev/null
+++ b/libxcb/doc/tutorial/xcb.css
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diff --git a/libxcb/doc/xcb.doxygen.in b/libxcb/doc/xcb.doxygen.in
new file mode 100644
index 000000000..58aa07630
--- /dev/null
+++ b/libxcb/doc/xcb.doxygen.in
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+# Doxyfile 1.5.0
+
+# This file describes the settings to be used by the documentation system
+# doxygen (www.doxygen.org) for a project
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+# If the ALWAYS_DETAILED_SEC and REPEAT_BRIEF tags are both set to YES then
+# Doxygen will generate a detailed section even if there is only a brief
+# description.
+
+ALWAYS_DETAILED_SEC = NO
+
+# If the INLINE_INHERITED_MEMB tag is set to YES, doxygen will show all
+# inherited members of a class in the documentation of that class as if those
+# members were ordinary class members. Constructors, destructors and assignment
+# operators of the base classes will not be shown.
+
+INLINE_INHERITED_MEMB = NO
+
+# If the FULL_PATH_NAMES tag is set to YES then Doxygen will prepend the full
+# path before files name in the file list and in the header files. If set
+# to NO the shortest path that makes the file name unique will be used.
+
+FULL_PATH_NAMES = NO
+
+# If the FULL_PATH_NAMES tag is set to YES then the STRIP_FROM_PATH tag
+# can be used to strip a user-defined part of the path. Stripping is
+# only done if one of the specified strings matches the left-hand part of
+# the path. The tag can be used to show relative paths in the file list.
+# If left blank the directory from which doxygen is run is used as the
+# path to strip.
+
+STRIP_FROM_PATH =
+
+# The STRIP_FROM_INC_PATH tag can be used to strip a user-defined part of
+# the path mentioned in the documentation of a class, which tells
+# the reader which header file to include in order to use a class.
+# If left blank only the name of the header file containing the class
+# definition is used. Otherwise one should specify the include paths that
+# are normally passed to the compiler using the -I flag.
+
+STRIP_FROM_INC_PATH =
+
+# If the SHORT_NAMES tag is set to YES, doxygen will generate much shorter
+# (but less readable) file names. This can be useful is your file systems
+# doesn't support long names like on DOS, Mac, or CD-ROM.
+
+SHORT_NAMES = NO
+
+# If the JAVADOC_AUTOBRIEF tag is set to YES then Doxygen
+# will interpret the first line (until the first dot) of a JavaDoc-style
+# comment as the brief description. If set to NO, the JavaDoc
+# comments will behave just like the Qt-style comments (thus requiring an
+# explicit @brief command for a brief description.
+
+JAVADOC_AUTOBRIEF = NO
+
+# The MULTILINE_CPP_IS_BRIEF tag can be set to YES to make Doxygen
+# treat a multi-line C++ special comment block (i.e. a block of //! or ///
+# comments) as a brief description. This used to be the default behaviour.
+# The new default is to treat a multi-line C++ comment block as a detailed
+# description. Set this tag to YES if you prefer the old behaviour instead.
+
+MULTILINE_CPP_IS_BRIEF = NO
+
+# If the DETAILS_AT_TOP tag is set to YES then Doxygen
+# will output the detailed description near the top, like JavaDoc.
+# If set to NO, the detailed description appears after the member
+# documentation.
+
+DETAILS_AT_TOP = NO
+
+# If the INHERIT_DOCS tag is set to YES (the default) then an undocumented
+# member inherits the documentation from any documented member that it
+# re-implements.
+
+INHERIT_DOCS = YES
+
+# If the SEPARATE_MEMBER_PAGES tag is set to YES, then doxygen will produce
+# a new page for each member. If set to NO, the documentation of a member will
+# be part of the file/class/namespace that contains it.
+
+SEPARATE_MEMBER_PAGES = NO
+
+# The TAB_SIZE tag can be used to set the number of spaces in a tab.
+# Doxygen uses this value to replace tabs by spaces in code fragments.
+
+TAB_SIZE = 8
+
+# This tag can be used to specify a number of aliases that acts
+# as commands in the documentation. An alias has the form "name=value".
+# For example adding "sideeffect=\par Side Effects:\n" will allow you to
+# put the command \sideeffect (or @sideeffect) in the documentation, which
+# will result in a user-defined paragraph with heading "Side Effects:".
+# You can put \n's in the value part of an alias to insert newlines.
+
+ALIASES =
+
+# Set the OPTIMIZE_OUTPUT_FOR_C tag to YES if your project consists of C
+# sources only. Doxygen will then generate output that is more tailored for C.
+# For instance, some of the names that are used will be different. The list
+# of all members will be omitted, etc.
+
+OPTIMIZE_OUTPUT_FOR_C = YES
+
+# Set the OPTIMIZE_OUTPUT_JAVA tag to YES if your project consists of Java
+# sources only. Doxygen will then generate output that is more tailored for Java.
+# For instance, namespaces will be presented as packages, qualified scopes
+# will look different, etc.
+
+OPTIMIZE_OUTPUT_JAVA = NO
+
+# If you use STL classes (i.e. std::string, std::vector, etc.) but do not want to
+# include (a tag file for) the STL sources as input, then you should
+# set this tag to YES in order to let doxygen match functions declarations and
+# definitions whose arguments contain STL classes (e.g. func(std::string); v.s.
+# func(std::string) {}). This also make the inheritance and collaboration
+# diagrams that involve STL classes more complete and accurate.
+
+BUILTIN_STL_SUPPORT = NO
+
+# If member grouping is used in the documentation and the DISTRIBUTE_GROUP_DOC
+# tag is set to YES, then doxygen will reuse the documentation of the first
+# member in the group (if any) for the other members of the group. By default
+# all members of a group must be documented explicitly.
+
+DISTRIBUTE_GROUP_DOC = NO
+
+# Set the SUBGROUPING tag to YES (the default) to allow class member groups of
+# the same type (for instance a group of public functions) to be put as a
+# subgroup of that type (e.g. under the Public Functions section). Set it to
+# NO to prevent subgrouping. Alternatively, this can be done per class using
+# the \nosubgrouping command.
+
+SUBGROUPING = YES
+
+#---------------------------------------------------------------------------
+# Build related configuration options
+#---------------------------------------------------------------------------
+
+# If the EXTRACT_ALL tag is set to YES doxygen will assume all entities in
+# documentation are documented, even if no documentation was available.
+# Private class members and static file members will be hidden unless
+# the EXTRACT_PRIVATE and EXTRACT_STATIC tags are set to YES
+
+EXTRACT_ALL = NO
+
+# If the EXTRACT_PRIVATE tag is set to YES all private members of a class
+# will be included in the documentation.
+
+EXTRACT_PRIVATE = NO
+
+# If the EXTRACT_STATIC tag is set to YES all static members of a file
+# will be included in the documentation.
+
+EXTRACT_STATIC = NO
+
+# If the EXTRACT_LOCAL_CLASSES tag is set to YES classes (and structs)
+# defined locally in source files will be included in the documentation.
+# If set to NO only classes defined in header files are included.
+
+EXTRACT_LOCAL_CLASSES = YES
+
+# This flag is only useful for Objective-C code. When set to YES local
+# methods, which are defined in the implementation section but not in
+# the interface are included in the documentation.
+# If set to NO (the default) only methods in the interface are included.
+
+EXTRACT_LOCAL_METHODS = NO
+
+# If the HIDE_UNDOC_MEMBERS tag is set to YES, Doxygen will hide all
+# undocumented members of documented classes, files or namespaces.
+# If set to NO (the default) these members will be included in the
+# various overviews, but no documentation section is generated.
+# This option has no effect if EXTRACT_ALL is enabled.
+
+HIDE_UNDOC_MEMBERS = NO
+
+# If the HIDE_UNDOC_CLASSES tag is set to YES, Doxygen will hide all
+# undocumented classes that are normally visible in the class hierarchy.
+# If set to NO (the default) these classes will be included in the various
+# overviews. This option has no effect if EXTRACT_ALL is enabled.
+
+HIDE_UNDOC_CLASSES = NO
+
+# If the HIDE_FRIEND_COMPOUNDS tag is set to YES, Doxygen will hide all
+# friend (class|struct|union) declarations.
+# If set to NO (the default) these declarations will be included in the
+# documentation.
+
+HIDE_FRIEND_COMPOUNDS = NO
+
+# If the HIDE_IN_BODY_DOCS tag is set to YES, Doxygen will hide any
+# documentation blocks found inside the body of a function.
+# If set to NO (the default) these blocks will be appended to the
+# function's detailed documentation block.
+
+HIDE_IN_BODY_DOCS = NO
+
+# The INTERNAL_DOCS tag determines if documentation
+# that is typed after a \internal command is included. If the tag is set
+# to NO (the default) then the documentation will be excluded.
+# Set it to YES to include the internal documentation.
+
+INTERNAL_DOCS = NO
+
+# If the CASE_SENSE_NAMES tag is set to NO then Doxygen will only generate
+# file names in lower-case letters. If set to YES upper-case letters are also
+# allowed. This is useful if you have classes or files whose names only differ
+# in case and if your file system supports case sensitive file names. Windows
+# and Mac users are advised to set this option to NO.
+
+CASE_SENSE_NAMES = YES
+
+# If the HIDE_SCOPE_NAMES tag is set to NO (the default) then Doxygen
+# will show members with their full class and namespace scopes in the
+# documentation. If set to YES the scope will be hidden.
+
+HIDE_SCOPE_NAMES = NO
+
+# If the SHOW_INCLUDE_FILES tag is set to YES (the default) then Doxygen
+# will put a list of the files that are included by a file in the documentation
+# of that file.
+
+SHOW_INCLUDE_FILES = YES
+
+# If the INLINE_INFO tag is set to YES (the default) then a tag [inline]
+# is inserted in the documentation for inline members.
+
+INLINE_INFO = YES
+
+# If the SORT_MEMBER_DOCS tag is set to YES (the default) then doxygen
+# will sort the (detailed) documentation of file and class members
+# alphabetically by member name. If set to NO the members will appear in
+# declaration order.
+
+SORT_MEMBER_DOCS = YES
+
+# If the SORT_BRIEF_DOCS tag is set to YES then doxygen will sort the
+# brief documentation of file, namespace and class members alphabetically
+# by member name. If set to NO (the default) the members will appear in
+# declaration order.
+
+SORT_BRIEF_DOCS = NO
+
+# If the SORT_BY_SCOPE_NAME tag is set to YES, the class list will be
+# sorted by fully-qualified names, including namespaces. If set to
+# NO (the default), the class list will be sorted only by class name,
+# not including the namespace part.
+# Note: This option is not very useful if HIDE_SCOPE_NAMES is set to YES.
+# Note: This option applies only to the class list, not to the
+# alphabetical list.
+
+SORT_BY_SCOPE_NAME = NO
+
+# The GENERATE_TODOLIST tag can be used to enable (YES) or
+# disable (NO) the todo list. This list is created by putting \todo
+# commands in the documentation.
+
+GENERATE_TODOLIST = YES
+
+# The GENERATE_TESTLIST tag can be used to enable (YES) or
+# disable (NO) the test list. This list is created by putting \test
+# commands in the documentation.
+
+GENERATE_TESTLIST = YES
+
+# The GENERATE_BUGLIST tag can be used to enable (YES) or
+# disable (NO) the bug list. This list is created by putting \bug
+# commands in the documentation.
+
+GENERATE_BUGLIST = YES
+
+# The GENERATE_DEPRECATEDLIST tag can be used to enable (YES) or
+# disable (NO) the deprecated list. This list is created by putting
+# \deprecated commands in the documentation.
+
+GENERATE_DEPRECATEDLIST= YES
+
+# The ENABLED_SECTIONS tag can be used to enable conditional
+# documentation sections, marked by \if sectionname ... \endif.
+
+ENABLED_SECTIONS =
+
+# The MAX_INITIALIZER_LINES tag determines the maximum number of lines
+# the initial value of a variable or define consists of for it to appear in
+# the documentation. If the initializer consists of more lines than specified
+# here it will be hidden. Use a value of 0 to hide initializers completely.
+# The appearance of the initializer of individual variables and defines in the
+# documentation can be controlled using \showinitializer or \hideinitializer
+# command in the documentation regardless of this setting.
+
+MAX_INITIALIZER_LINES = 30
+
+# Set the SHOW_USED_FILES tag to NO to disable the list of files generated
+# at the bottom of the documentation of classes and structs. If set to YES the
+# list will mention the files that were used to generate the documentation.
+
+SHOW_USED_FILES = YES
+
+# If the sources in your project are distributed over multiple directories
+# then setting the SHOW_DIRECTORIES tag to YES will show the directory hierarchy
+# in the documentation. The default is NO.
+
+SHOW_DIRECTORIES = NO
+
+# The FILE_VERSION_FILTER tag can be used to specify a program or script that
+# doxygen should invoke to get the current version for each file (typically from the
+# version control system). Doxygen will invoke the program by executing (via
+# popen()) the command <command> <input-file>, where <command> is the value of
+# the FILE_VERSION_FILTER tag, and <input-file> is the name of an input file
+# provided by doxygen. Whatever the program writes to standard output
+# is used as the file version. See the manual for examples.
+
+FILE_VERSION_FILTER =
+
+#---------------------------------------------------------------------------
+# configuration options related to warning and progress messages
+#---------------------------------------------------------------------------
+
+# The QUIET tag can be used to turn on/off the messages that are generated
+# by doxygen. Possible values are YES and NO. If left blank NO is used.
+
+QUIET = YES
+
+# The WARNINGS tag can be used to turn on/off the warning messages that are
+# generated by doxygen. Possible values are YES and NO. If left blank
+# NO is used.
+
+WARNINGS = YES
+
+# If WARN_IF_UNDOCUMENTED is set to YES, then doxygen will generate warnings
+# for undocumented members. If EXTRACT_ALL is set to YES then this flag will
+# automatically be disabled.
+
+# XXX: In the future this should be turned on. For now it generates too much noise.
+WARN_IF_UNDOCUMENTED = NO
+
+# If WARN_IF_DOC_ERROR is set to YES, doxygen will generate warnings for
+# potential errors in the documentation, such as not documenting some
+# parameters in a documented function, or documenting parameters that
+# don't exist or using markup commands wrongly.
+
+WARN_IF_DOC_ERROR = YES
+
+# This WARN_NO_PARAMDOC option can be abled to get warnings for
+# functions that are documented, but have no documentation for their parameters
+# or return value. If set to NO (the default) doxygen will only warn about
+# wrong or incomplete parameter documentation, but not about the absence of
+# documentation.
+
+WARN_NO_PARAMDOC = YES
+
+# The WARN_FORMAT tag determines the format of the warning messages that
+# doxygen can produce. The string should contain the $file, $line, and $text
+# tags, which will be replaced by the file and line number from which the
+# warning originated and the warning text. Optionally the format may contain
+# $version, which will be replaced by the version of the file (if it could
+# be obtained via FILE_VERSION_FILTER)
+
+WARN_FORMAT = "$file:$line: $text"
+
+# The WARN_LOGFILE tag can be used to specify a file to which warning
+# and error messages should be written. If left blank the output is written
+# to stderr.
+
+WARN_LOGFILE =
+
+#---------------------------------------------------------------------------
+# configuration options related to the input files
+#---------------------------------------------------------------------------
+
+# The INPUT tag can be used to specify the files and/or directories that contain
+# documented source files. You may enter file names like "myfile.cpp" or
+# directories like "/usr/src/myproject". Separate the files or directories
+# with spaces.
+
+INPUT = @top_srcdir@/src @top_builddir@/src
+
+# If the value of the INPUT tag contains directories, you can use the
+# FILE_PATTERNS tag to specify one or more wildcard pattern (like *.cpp
+# and *.h) to filter out the source-files in the directories. If left
+# blank the following patterns are tested:
+# *.c *.cc *.cxx *.cpp *.c++ *.java *.ii *.ixx *.ipp *.i++ *.inl *.h *.hh *.hxx
+# *.hpp *.h++ *.idl *.odl *.cs *.php *.php3 *.inc *.m *.mm *.py
+
+FILE_PATTERNS =
+
+# The RECURSIVE tag can be used to turn specify whether or not subdirectories
+# should be searched for input files as well. Possible values are YES and NO.
+# If left blank NO is used.
+
+RECURSIVE = NO
+
+# The EXCLUDE tag can be used to specify files and/or directories that should
+# excluded from the INPUT source files. This way you can easily exclude a
+# subdirectory from a directory tree whose root is specified with the INPUT tag.
+
+EXCLUDE =
+
+# The EXCLUDE_SYMLINKS tag can be used select whether or not files or
+# directories that are symbolic links (a Unix filesystem feature) are excluded
+# from the input.
+
+EXCLUDE_SYMLINKS = NO
+
+# If the value of the INPUT tag contains directories, you can use the
+# EXCLUDE_PATTERNS tag to specify one or more wildcard patterns to exclude
+# certain files from those directories. Note that the wildcards are matched
+# against the file with absolute path, so to exclude all test directories
+# for example use the pattern */test/*
+
+EXCLUDE_PATTERNS =
+
+# The EXAMPLE_PATH tag can be used to specify one or more files or
+# directories that contain example code fragments that are included (see
+# the \include command).
+
+EXAMPLE_PATH =
+
+# If the value of the EXAMPLE_PATH tag contains directories, you can use the
+# EXAMPLE_PATTERNS tag to specify one or more wildcard pattern (like *.cpp
+# and *.h) to filter out the source-files in the directories. If left
+# blank all files are included.
+
+EXAMPLE_PATTERNS =
+
+# If the EXAMPLE_RECURSIVE tag is set to YES then subdirectories will be
+# searched for input files to be used with the \include or \dontinclude
+# commands irrespective of the value of the RECURSIVE tag.
+# Possible values are YES and NO. If left blank NO is used.
+
+EXAMPLE_RECURSIVE = NO
+
+# The IMAGE_PATH tag can be used to specify one or more files or
+# directories that contain image that are included in the documentation (see
+# the \image command).
+
+IMAGE_PATH =
+
+# The INPUT_FILTER tag can be used to specify a program that doxygen should
+# invoke to filter for each input file. Doxygen will invoke the filter program
+# by executing (via popen()) the command <filter> <input-file>, where <filter>
+# is the value of the INPUT_FILTER tag, and <input-file> is the name of an
+# input file. Doxygen will then use the output that the filter program writes
+# to standard output. If FILTER_PATTERNS is specified, this tag will be
+# ignored.
+
+INPUT_FILTER =
+
+# The FILTER_PATTERNS tag can be used to specify filters on a per file pattern
+# basis. Doxygen will compare the file name with each pattern and apply the
+# filter if there is a match. The filters are a list of the form:
+# pattern=filter (like *.cpp=my_cpp_filter). See INPUT_FILTER for further
+# info on how filters are used. If FILTER_PATTERNS is empty, INPUT_FILTER
+# is applied to all files.
+
+FILTER_PATTERNS =
+
+# If the FILTER_SOURCE_FILES tag is set to YES, the input filter (if set using
+# INPUT_FILTER) will be used to filter the input files when producing source
+# files to browse (i.e. when SOURCE_BROWSER is set to YES).
+
+FILTER_SOURCE_FILES = NO
+
+#---------------------------------------------------------------------------
+# configuration options related to source browsing
+#---------------------------------------------------------------------------
+
+# If the SOURCE_BROWSER tag is set to YES then a list of source files will
+# be generated. Documented entities will be cross-referenced with these sources.
+# Note: To get rid of all source code in the generated output, make sure also
+# VERBATIM_HEADERS is set to NO.
+
+SOURCE_BROWSER = NO
+
+# Setting the INLINE_SOURCES tag to YES will include the body
+# of functions and classes directly in the documentation.
+
+INLINE_SOURCES = NO
+
+# Setting the STRIP_CODE_COMMENTS tag to YES (the default) will instruct
+# doxygen to hide any special comment blocks from generated source code
+# fragments. Normal C and C++ comments will always remain visible.
+
+STRIP_CODE_COMMENTS = YES
+
+# If the REFERENCED_BY_RELATION tag is set to YES (the default)
+# then for each documented function all documented
+# functions referencing it will be listed.
+
+REFERENCED_BY_RELATION = YES
+
+# If the REFERENCES_RELATION tag is set to YES (the default)
+# then for each documented function all documented entities
+# called/used by that function will be listed.
+
+REFERENCES_RELATION = YES
+
+# If the REFERENCES_LINK_SOURCE tag is set to YES (the default)
+# and SOURCE_BROWSER tag is set to YES, then the hyperlinks from
+# functions in REFERENCES_RELATION and REFERENCED_BY_RELATION lists will
+# link to the source code. Otherwise they will link to the documentstion.
+
+REFERENCES_LINK_SOURCE = YES
+
+# If the USE_HTAGS tag is set to YES then the references to source code
+# will point to the HTML generated by the htags(1) tool instead of doxygen
+# built-in source browser. The htags tool is part of GNU's global source
+# tagging system (see http://www.gnu.org/software/global/global.html). You
+# will need version 4.8.6 or higher.
+
+USE_HTAGS = NO
+
+# If the VERBATIM_HEADERS tag is set to YES (the default) then Doxygen
+# will generate a verbatim copy of the header file for each class for
+# which an include is specified. Set to NO to disable this.
+
+VERBATIM_HEADERS = YES
+
+#---------------------------------------------------------------------------
+# configuration options related to the alphabetical class index
+#---------------------------------------------------------------------------
+
+# If the ALPHABETICAL_INDEX tag is set to YES, an alphabetical index
+# of all compounds will be generated. Enable this if the project
+# contains a lot of classes, structs, unions or interfaces.
+
+ALPHABETICAL_INDEX = NO
+
+# If the alphabetical index is enabled (see ALPHABETICAL_INDEX) then
+# the COLS_IN_ALPHA_INDEX tag can be used to specify the number of columns
+# in which this list will be split (can be a number in the range [1..20])
+
+COLS_IN_ALPHA_INDEX = 5
+
+# In case all classes in a project start with a common prefix, all
+# classes will be put under the same header in the alphabetical index.
+# The IGNORE_PREFIX tag can be used to specify one or more prefixes that
+# should be ignored while generating the index headers.
+
+IGNORE_PREFIX =
+
+#---------------------------------------------------------------------------
+# configuration options related to the HTML output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_HTML tag is set to YES (the default) Doxygen will
+# generate HTML output.
+
+GENERATE_HTML = YES
+
+# The HTML_OUTPUT tag is used to specify where the HTML docs will be put.
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be
+# put in front of it. If left blank `html' will be used as the default path.
+
+HTML_OUTPUT = manual
+
+# The HTML_FILE_EXTENSION tag can be used to specify the file extension for
+# each generated HTML page (for example: .htm,.php,.asp). If it is left blank
+# doxygen will generate files with .html extension.
+
+HTML_FILE_EXTENSION = .html
+
+# The HTML_HEADER tag can be used to specify a personal HTML header for
+# each generated HTML page. If it is left blank doxygen will generate a
+# standard header.
+
+HTML_HEADER =
+
+# The HTML_FOOTER tag can be used to specify a personal HTML footer for
+# each generated HTML page. If it is left blank doxygen will generate a
+# standard footer.
+
+HTML_FOOTER =
+
+# The HTML_STYLESHEET tag can be used to specify a user-defined cascading
+# style sheet that is used by each HTML page. It can be used to
+# fine-tune the look of the HTML output. If the tag is left blank doxygen
+# will generate a default style sheet. Note that doxygen will try to copy
+# the style sheet file to the HTML output directory, so don't put your own
+# stylesheet in the HTML output directory as well, or it will be erased!
+
+HTML_STYLESHEET =
+
+# If the HTML_ALIGN_MEMBERS tag is set to YES, the members of classes,
+# files or namespaces will be aligned in HTML using tables. If set to
+# NO a bullet list will be used.
+
+HTML_ALIGN_MEMBERS = YES
+
+# If the GENERATE_HTMLHELP tag is set to YES, additional index files
+# will be generated that can be used as input for tools like the
+# Microsoft HTML help workshop to generate a compressed HTML help file (.chm)
+# of the generated HTML documentation.
+
+GENERATE_HTMLHELP = NO
+
+# If the GENERATE_HTMLHELP tag is set to YES, the CHM_FILE tag can
+# be used to specify the file name of the resulting .chm file. You
+# can add a path in front of the file if the result should not be
+# written to the html output directory.
+
+CHM_FILE =
+
+# If the GENERATE_HTMLHELP tag is set to YES, the HHC_LOCATION tag can
+# be used to specify the location (absolute path including file name) of
+# the HTML help compiler (hhc.exe). If non-empty doxygen will try to run
+# the HTML help compiler on the generated index.hhp.
+
+HHC_LOCATION =
+
+# If the GENERATE_HTMLHELP tag is set to YES, the GENERATE_CHI flag
+# controls if a separate .chi index file is generated (YES) or that
+# it should be included in the master .chm file (NO).
+
+GENERATE_CHI = NO
+
+# If the GENERATE_HTMLHELP tag is set to YES, the BINARY_TOC flag
+# controls whether a binary table of contents is generated (YES) or a
+# normal table of contents (NO) in the .chm file.
+
+BINARY_TOC = NO
+
+# The TOC_EXPAND flag can be set to YES to add extra items for group members
+# to the contents of the HTML help documentation and to the tree view.
+
+TOC_EXPAND = NO
+
+# The DISABLE_INDEX tag can be used to turn on/off the condensed index at
+# top of each HTML page. The value NO (the default) enables the index and
+# the value YES disables it.
+
+DISABLE_INDEX = NO
+
+# This tag can be used to set the number of enum values (range [1..20])
+# that doxygen will group on one line in the generated HTML documentation.
+
+ENUM_VALUES_PER_LINE = 4
+
+# If the GENERATE_TREEVIEW tag is set to YES, a side panel will be
+# generated containing a tree-like index structure (just like the one that
+# is generated for HTML Help). For this to work a browser that supports
+# JavaScript, DHTML, CSS and frames is required (for instance Mozilla 1.0+,
+# Netscape 6.0+, Internet explorer 5.0+, or Konqueror). Windows users are
+# probably better off using the HTML help feature.
+
+GENERATE_TREEVIEW = NO
+
+# If the treeview is enabled (see GENERATE_TREEVIEW) then this tag can be
+# used to set the initial width (in pixels) of the frame in which the tree
+# is shown.
+
+TREEVIEW_WIDTH = 250
+
+#---------------------------------------------------------------------------
+# configuration options related to the LaTeX output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_LATEX tag is set to YES (the default) Doxygen will
+# generate Latex output.
+
+GENERATE_LATEX = NO
+
+# The LATEX_OUTPUT tag is used to specify where the LaTeX docs will be put.
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be
+# put in front of it. If left blank `latex' will be used as the default path.
+
+LATEX_OUTPUT = latex
+
+# The LATEX_CMD_NAME tag can be used to specify the LaTeX command name to be
+# invoked. If left blank `latex' will be used as the default command name.
+
+LATEX_CMD_NAME = latex
+
+# The MAKEINDEX_CMD_NAME tag can be used to specify the command name to
+# generate index for LaTeX. If left blank `makeindex' will be used as the
+# default command name.
+
+MAKEINDEX_CMD_NAME = makeindex
+
+# If the COMPACT_LATEX tag is set to YES Doxygen generates more compact
+# LaTeX documents. This may be useful for small projects and may help to
+# save some trees in general.
+
+COMPACT_LATEX = NO
+
+# The PAPER_TYPE tag can be used to set the paper type that is used
+# by the printer. Possible values are: a4, a4wide, letter, legal and
+# executive. If left blank a4wide will be used.
+
+PAPER_TYPE = a4wide
+
+# The EXTRA_PACKAGES tag can be to specify one or more names of LaTeX
+# packages that should be included in the LaTeX output.
+
+EXTRA_PACKAGES =
+
+# The LATEX_HEADER tag can be used to specify a personal LaTeX header for
+# the generated latex document. The header should contain everything until
+# the first chapter. If it is left blank doxygen will generate a
+# standard header. Notice: only use this tag if you know what you are doing!
+
+LATEX_HEADER =
+
+# If the PDF_HYPERLINKS tag is set to YES, the LaTeX that is generated
+# is prepared for conversion to pdf (using ps2pdf). The pdf file will
+# contain links (just like the HTML output) instead of page references
+# This makes the output suitable for online browsing using a pdf viewer.
+
+PDF_HYPERLINKS = NO
+
+# If the USE_PDFLATEX tag is set to YES, pdflatex will be used instead of
+# plain latex in the generated Makefile. Set this option to YES to get a
+# higher quality PDF documentation.
+
+USE_PDFLATEX = NO
+
+# If the LATEX_BATCHMODE tag is set to YES, doxygen will add the \\batchmode.
+# command to the generated LaTeX files. This will instruct LaTeX to keep
+# running if errors occur, instead of asking the user for help.
+# This option is also used when generating formulas in HTML.
+
+LATEX_BATCHMODE = NO
+
+# If LATEX_HIDE_INDICES is set to YES then doxygen will not
+# include the index chapters (such as File Index, Compound Index, etc.)
+# in the output.
+
+LATEX_HIDE_INDICES = NO
+
+#---------------------------------------------------------------------------
+# configuration options related to the RTF output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_RTF tag is set to YES Doxygen will generate RTF output
+# The RTF output is optimized for Word 97 and may not look very pretty with
+# other RTF readers or editors.
+
+GENERATE_RTF = NO
+
+# The RTF_OUTPUT tag is used to specify where the RTF docs will be put.
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be
+# put in front of it. If left blank `rtf' will be used as the default path.
+
+RTF_OUTPUT = rtf
+
+# If the COMPACT_RTF tag is set to YES Doxygen generates more compact
+# RTF documents. This may be useful for small projects and may help to
+# save some trees in general.
+
+COMPACT_RTF = NO
+
+# If the RTF_HYPERLINKS tag is set to YES, the RTF that is generated
+# will contain hyperlink fields. The RTF file will
+# contain links (just like the HTML output) instead of page references.
+# This makes the output suitable for online browsing using WORD or other
+# programs which support those fields.
+# Note: wordpad (write) and others do not support links.
+
+RTF_HYPERLINKS = NO
+
+# Load stylesheet definitions from file. Syntax is similar to doxygen's
+# config file, i.e. a series of assignments. You only have to provide
+# replacements, missing definitions are set to their default value.
+
+RTF_STYLESHEET_FILE =
+
+# Set optional variables used in the generation of an rtf document.
+# Syntax is similar to doxygen's config file.
+
+RTF_EXTENSIONS_FILE =
+
+#---------------------------------------------------------------------------
+# configuration options related to the man page output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_MAN tag is set to YES (the default) Doxygen will
+# generate man pages
+
+GENERATE_MAN = NO
+
+# The MAN_OUTPUT tag is used to specify where the man pages will be put.
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be
+# put in front of it. If left blank `man' will be used as the default path.
+
+MAN_OUTPUT = man
+
+# The MAN_EXTENSION tag determines the extension that is added to
+# the generated man pages (default is the subroutine's section .3)
+
+MAN_EXTENSION = .3
+
+# If the MAN_LINKS tag is set to YES and Doxygen generates man output,
+# then it will generate one additional man file for each entity
+# documented in the real man page(s). These additional files
+# only source the real man page, but without them the man command
+# would be unable to find the correct page. The default is NO.
+
+MAN_LINKS = NO
+
+#---------------------------------------------------------------------------
+# configuration options related to the XML output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_XML tag is set to YES Doxygen will
+# generate an XML file that captures the structure of
+# the code including all documentation.
+
+GENERATE_XML = NO
+
+# The XML_OUTPUT tag is used to specify where the XML pages will be put.
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be
+# put in front of it. If left blank `xml' will be used as the default path.
+
+XML_OUTPUT = xml
+
+# The XML_SCHEMA tag can be used to specify an XML schema,
+# which can be used by a validating XML parser to check the
+# syntax of the XML files.
+
+XML_SCHEMA =
+
+# The XML_DTD tag can be used to specify an XML DTD,
+# which can be used by a validating XML parser to check the
+# syntax of the XML files.
+
+XML_DTD =
+
+# If the XML_PROGRAMLISTING tag is set to YES Doxygen will
+# dump the program listings (including syntax highlighting
+# and cross-referencing information) to the XML output. Note that
+# enabling this will significantly increase the size of the XML output.
+
+XML_PROGRAMLISTING = YES
+
+#---------------------------------------------------------------------------
+# configuration options for the AutoGen Definitions output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_AUTOGEN_DEF tag is set to YES Doxygen will
+# generate an AutoGen Definitions (see autogen.sf.net) file
+# that captures the structure of the code including all
+# documentation. Note that this feature is still experimental
+# and incomplete at the moment.
+
+GENERATE_AUTOGEN_DEF = NO
+
+#---------------------------------------------------------------------------
+# configuration options related to the Perl module output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_PERLMOD tag is set to YES Doxygen will
+# generate a Perl module file that captures the structure of
+# the code including all documentation. Note that this
+# feature is still experimental and incomplete at the
+# moment.
+
+GENERATE_PERLMOD = NO
+
+# If the PERLMOD_LATEX tag is set to YES Doxygen will generate
+# the necessary Makefile rules, Perl scripts and LaTeX code to be able
+# to generate PDF and DVI output from the Perl module output.
+
+PERLMOD_LATEX = NO
+
+# If the PERLMOD_PRETTY tag is set to YES the Perl module output will be
+# nicely formatted so it can be parsed by a human reader. This is useful
+# if you want to understand what is going on. On the other hand, if this
+# tag is set to NO the size of the Perl module output will be much smaller
+# and Perl will parse it just the same.
+
+PERLMOD_PRETTY = YES
+
+# The names of the make variables in the generated doxyrules.make file
+# are prefixed with the string contained in PERLMOD_MAKEVAR_PREFIX.
+# This is useful so different doxyrules.make files included by the same
+# Makefile don't overwrite each other's variables.
+
+PERLMOD_MAKEVAR_PREFIX =
+
+#---------------------------------------------------------------------------
+# Configuration options related to the preprocessor
+#---------------------------------------------------------------------------
+
+# If the ENABLE_PREPROCESSING tag is set to YES (the default) Doxygen will
+# evaluate all C-preprocessor directives found in the sources and include
+# files.
+
+ENABLE_PREPROCESSING = YES
+
+# If the MACRO_EXPANSION tag is set to YES Doxygen will expand all macro
+# names in the source code. If set to NO (the default) only conditional
+# compilation will be performed. Macro expansion can be done in a controlled
+# way by setting EXPAND_ONLY_PREDEF to YES.
+
+MACRO_EXPANSION = NO
+
+# If the EXPAND_ONLY_PREDEF and MACRO_EXPANSION tags are both set to YES
+# then the macro expansion is limited to the macros specified with the
+# PREDEFINED and EXPAND_AS_DEFINED tags.
+
+EXPAND_ONLY_PREDEF = NO
+
+# If the SEARCH_INCLUDES tag is set to YES (the default) the includes files
+# in the INCLUDE_PATH (see below) will be search if a #include is found.
+
+SEARCH_INCLUDES = YES
+
+# The INCLUDE_PATH tag can be used to specify one or more directories that
+# contain include files that are not input files but should be processed by
+# the preprocessor.
+
+INCLUDE_PATH =
+
+# You can use the INCLUDE_FILE_PATTERNS tag to specify one or more wildcard
+# patterns (like *.h and *.hpp) to filter out the header-files in the
+# directories. If left blank, the patterns specified with FILE_PATTERNS will
+# be used.
+
+INCLUDE_FILE_PATTERNS =
+
+# The PREDEFINED tag can be used to specify one or more macro names that
+# are defined before the preprocessor is started (similar to the -D option of
+# gcc). The argument of the tag is a list of macros of the form: name
+# or name=definition (no spaces). If the definition and the = are
+# omitted =1 is assumed. To prevent a macro definition from being
+# undefined via #undef or recursively expanded use the := operator
+# instead of the = operator.
+
+PREDEFINED =
+
+# If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then
+# this tag can be used to specify a list of macro names that should be expanded.
+# The macro definition that is found in the sources will be used.
+# Use the PREDEFINED tag if you want to use a different macro definition.
+
+EXPAND_AS_DEFINED =
+
+# If the SKIP_FUNCTION_MACROS tag is set to YES (the default) then
+# doxygen's preprocessor will remove all function-like macros that are alone
+# on a line, have an all uppercase name, and do not end with a semicolon. Such
+# function macros are typically used for boiler-plate code, and will confuse
+# the parser if not removed.
+
+SKIP_FUNCTION_MACROS = YES
+
+#---------------------------------------------------------------------------
+# Configuration::additions related to external references
+#---------------------------------------------------------------------------
+
+# The TAGFILES option can be used to specify one or more tagfiles.
+# Optionally an initial location of the external documentation
+# can be added for each tagfile. The format of a tag file without
+# this location is as follows:
+# TAGFILES = file1 file2 ...
+# Adding location for the tag files is done as follows:
+# TAGFILES = file1=loc1 "file2 = loc2" ...
+# where "loc1" and "loc2" can be relative or absolute paths or
+# URLs. If a location is present for each tag, the installdox tool
+# does not have to be run to correct the links.
+# Note that each tag file must have a unique name
+# (where the name does NOT include the path)
+# If a tag file is not located in the directory in which doxygen
+# is run, you must also specify the path to the tagfile here.
+
+TAGFILES =
+
+# When a file name is specified after GENERATE_TAGFILE, doxygen will create
+# a tag file that is based on the input files it reads.
+
+GENERATE_TAGFILE =
+
+# If the ALLEXTERNALS tag is set to YES all external classes will be listed
+# in the class index. If set to NO only the inherited external classes
+# will be listed.
+
+ALLEXTERNALS = NO
+
+# If the EXTERNAL_GROUPS tag is set to YES all external groups will be listed
+# in the modules index. If set to NO, only the current project's groups will
+# be listed.
+
+EXTERNAL_GROUPS = YES
+
+# The PERL_PATH should be the absolute path and name of the perl script
+# interpreter (i.e. the result of `which perl').
+
+PERL_PATH = /usr/bin/perl
+
+#---------------------------------------------------------------------------
+# Configuration options related to the dot tool
+#---------------------------------------------------------------------------
+
+# If the CLASS_DIAGRAMS tag is set to YES (the default) Doxygen will
+# generate a inheritance diagram (in HTML, RTF and LaTeX) for classes with base
+# or super classes. Setting the tag to NO turns the diagrams off. Note that
+# this option is superseded by the HAVE_DOT option below. This is only a
+# fallback. It is recommended to install and use dot, since it yields more
+# powerful graphs.
+
+CLASS_DIAGRAMS = YES
+
+# If set to YES, the inheritance and collaboration graphs will hide
+# inheritance and usage relations if the target is undocumented
+# or is not a class.
+
+HIDE_UNDOC_RELATIONS = YES
+
+# If you set the HAVE_DOT tag to YES then doxygen will assume the dot tool is
+# available from the path. This tool is part of Graphviz, a graph visualization
+# toolkit from AT&T and Lucent Bell Labs. The other options in this section
+# have no effect if this option is set to NO (the default)
+
+HAVE_DOT = YES
+
+# If the CLASS_GRAPH and HAVE_DOT tags are set to YES then doxygen
+# will generate a graph for each documented class showing the direct and
+# indirect inheritance relations. Setting this tag to YES will force the
+# the CLASS_DIAGRAMS tag to NO.
+
+CLASS_GRAPH = YES
+
+# If the COLLABORATION_GRAPH and HAVE_DOT tags are set to YES then doxygen
+# will generate a graph for each documented class showing the direct and
+# indirect implementation dependencies (inheritance, containment, and
+# class references variables) of the class with other documented classes.
+
+COLLABORATION_GRAPH = YES
+
+# If the GROUP_GRAPHS and HAVE_DOT tags are set to YES then doxygen
+# will generate a graph for groups, showing the direct groups dependencies
+
+GROUP_GRAPHS = YES
+
+# If the UML_LOOK tag is set to YES doxygen will generate inheritance and
+# collaboration diagrams in a style similar to the OMG's Unified Modeling
+# Language.
+
+UML_LOOK = NO
+
+# If set to YES, the inheritance and collaboration graphs will show the
+# relations between templates and their instances.
+
+TEMPLATE_RELATIONS = NO
+
+# If the ENABLE_PREPROCESSING, SEARCH_INCLUDES, INCLUDE_GRAPH, and HAVE_DOT
+# tags are set to YES then doxygen will generate a graph for each documented
+# file showing the direct and indirect include dependencies of the file with
+# other documented files.
+
+INCLUDE_GRAPH = YES
+
+# If the ENABLE_PREPROCESSING, SEARCH_INCLUDES, INCLUDED_BY_GRAPH, and
+# HAVE_DOT tags are set to YES then doxygen will generate a graph for each
+# documented header file showing the documented files that directly or
+# indirectly include this file.
+
+INCLUDED_BY_GRAPH = YES
+
+# If the CALL_GRAPH and HAVE_DOT tags are set to YES then doxygen will
+# generate a call dependency graph for every global function or class method.
+# Note that enabling this option will significantly increase the time of a run.
+# So in most cases it will be better to enable call graphs for selected
+# functions only using the \callgraph command.
+
+CALL_GRAPH = NO
+
+# If the CALLER_GRAPH and HAVE_DOT tags are set to YES then doxygen will
+# generate a caller dependency graph for every global function or class method.
+# Note that enabling this option will significantly increase the time of a run.
+# So in most cases it will be better to enable caller graphs for selected
+# functions only using the \callergraph command.
+
+CALLER_GRAPH = NO
+
+# If the GRAPHICAL_HIERARCHY and HAVE_DOT tags are set to YES then doxygen
+# will graphical hierarchy of all classes instead of a textual one.
+
+GRAPHICAL_HIERARCHY = YES
+
+# If the DIRECTORY_GRAPH, SHOW_DIRECTORIES and HAVE_DOT tags are set to YES
+# then doxygen will show the dependencies a directory has on other directories
+# in a graphical way. The dependency relations are determined by the #include
+# relations between the files in the directories.
+
+DIRECTORY_GRAPH = YES
+
+# The DOT_IMAGE_FORMAT tag can be used to set the image format of the images
+# generated by dot. Possible values are png, jpg, or gif
+# If left blank png will be used.
+
+DOT_IMAGE_FORMAT = png
+
+# The tag DOT_PATH can be used to specify the path where the dot tool can be
+# found. If left blank, it is assumed the dot tool can be found in the path.
+
+DOT_PATH =
+
+# The DOTFILE_DIRS tag can be used to specify one or more directories that
+# contain dot files that are included in the documentation (see the
+# \dotfile command).
+
+DOTFILE_DIRS =
+
+# The MAX_DOT_GRAPH_WIDTH tag can be used to set the maximum allowed width
+# (in pixels) of the graphs generated by dot. If a graph becomes larger than
+# this value, doxygen will try to truncate the graph, so that it fits within
+# the specified constraint. Beware that most browsers cannot cope with very
+# large images.
+
+MAX_DOT_GRAPH_WIDTH = 1024
+
+# The MAX_DOT_GRAPH_HEIGHT tag can be used to set the maximum allows height
+# (in pixels) of the graphs generated by dot. If a graph becomes larger than
+# this value, doxygen will try to truncate the graph, so that it fits within
+# the specified constraint. Beware that most browsers cannot cope with very
+# large images.
+
+MAX_DOT_GRAPH_HEIGHT = 1024
+
+# The MAX_DOT_GRAPH_DEPTH tag can be used to set the maximum depth of the
+# graphs generated by dot. A depth value of 3 means that only nodes reachable
+# from the root by following a path via at most 3 edges will be shown. Nodes
+# that lay further from the root node will be omitted. Note that setting this
+# option to 1 or 2 may greatly reduce the computation time needed for large
+# code bases. Also note that a graph may be further truncated if the graph's
+# image dimensions are not sufficient to fit the graph (see MAX_DOT_GRAPH_WIDTH
+# and MAX_DOT_GRAPH_HEIGHT). If 0 is used for the depth value (the default),
+# the graph is not depth-constrained.
+
+MAX_DOT_GRAPH_DEPTH = 0
+
+# Set the DOT_TRANSPARENT tag to YES to generate images with a transparent
+# background. This is disabled by default, which results in a white background.
+# Warning: Depending on the platform used, enabling this option may lead to
+# badly anti-aliased labels on the edges of a graph (i.e. they become hard to
+# read).
+
+DOT_TRANSPARENT = NO
+
+# Set the DOT_MULTI_TARGETS tag to YES allow dot to generate multiple output
+# files in one run (i.e. multiple -o and -T options on the command line). This
+# makes dot run faster, but since only newer versions of dot (>1.8.10)
+# support this, this feature is disabled by default.
+
+DOT_MULTI_TARGETS = NO
+
+# If the GENERATE_LEGEND tag is set to YES (the default) Doxygen will
+# generate a legend page explaining the meaning of the various boxes and
+# arrows in the dot generated graphs.
+
+GENERATE_LEGEND = YES
+
+# If the DOT_CLEANUP tag is set to YES (the default) Doxygen will
+# remove the intermediate dot files that are used to generate
+# the various graphs.
+
+DOT_CLEANUP = YES
+
+#---------------------------------------------------------------------------
+# Configuration::additions related to the search engine
+#---------------------------------------------------------------------------
+
+# The SEARCHENGINE tag specifies whether or not a search engine should be
+# used. If set to NO the values of all tags below this one will be ignored.
+
+SEARCHENGINE = NO