@@ 148,6 148,14 @@ private:
 
 #define CONFIG_RESIZE_UPDATE      True
 
+// If USE_COMPOSITE is true, wmx will enable composite redirects for
+// all windows if the Composite extension is present.  This should
+// make no difference at all to the appearance or behaviour of wmx,
+// but it may make it substantially faster with modern video cards
+// that optimise rendering more than old-fashioned window operations.
+
+#define CONFIG_USE_COMPOSITE      True
+
 // If RAISELOWER_ON_CLICK is True, clicking on the title of the
 // topmost window will lower instead of raising it (patch due to
 // Kazushi (Jam) Marukawa)

          

@@ 15,6 15,10 @@ 
 #include "Cursors.h"
 #include <X11/cursorfont.h>
 
+#ifdef CONFIG_USE_COMPOSITE
+#include <X11/extensions/Xcomposite.h>
+#endif
+
 Atom    Atoms::wm_state;
 Atom    Atoms::wm_changeState;
 Atom    Atoms::wm_protocols;

          
@@ 225,6 229,17 @@ WindowManager::WindowManager(int argc, c
 
     fprintf(stderr, "\n     NETWM compliant.");
 
+#ifdef CONFIG_USE_COMPOSITE
+    int ev, er;
+    if (XCompositeQueryExtension(m_display, &ev, &er)) {
+        fprintf(stderr, "  Composite extension enabled.");
+        for (int i = 0; i < m_screensTotal; ++i) {
+            XCompositeRedirectSubwindows(m_display, RootWindow(m_display, i),
+                                         CompositeRedirectAutomatic);
+        }
+    }
+#endif
+
     fprintf(stderr, "\n     Command menu taken from ");
     if (wmxdir == NULL) {
 	fprintf(stderr, "%s/%s.\n", home, CONFIG_COMMAND_MENU);

          

@@ 3020,6 3020,83 @@ fi
 
 
 
+{ echo "$as_me:$LINENO: checking for XCompositeQueryExtension in -lXcomposite" >&5
+echo $ECHO_N "checking for XCompositeQueryExtension in -lXcomposite... $ECHO_C" >&6; }
+if test "${ac_cv_lib_Xcomposite_XCompositeQueryExtension+set}" = set; then
+  echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lXcomposite  $LIBS"
+cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char XCompositeQueryExtension ();
+int
+main ()
+{
+return XCompositeQueryExtension ();
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (ac_try="$ac_link"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+  (eval "$ac_link") 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && {
+	 test -z "$ac_cxx_werror_flag" ||
+	 test ! -s conftest.err
+       } && test -s conftest$ac_exeext &&
+       $as_test_x conftest$ac_exeext; then
+  ac_cv_lib_Xcomposite_XCompositeQueryExtension=yes
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+	ac_cv_lib_Xcomposite_XCompositeQueryExtension=no
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
+      conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ echo "$as_me:$LINENO: result: $ac_cv_lib_Xcomposite_XCompositeQueryExtension" >&5
+echo "${ECHO_T}$ac_cv_lib_Xcomposite_XCompositeQueryExtension" >&6; }
+if test $ac_cv_lib_Xcomposite_XCompositeQueryExtension = yes; then
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_LIBXCOMPOSITE 1
+_ACEOF
+
+  LIBS="-lXcomposite $LIBS"
+
+else
+
+    echo "Warning: Xcomposite library not found"
+    echo "Please either install the Xcomposite library and headers, or ensure you have CONFIG_USE_COMPOSITE set to False in Config.h"
+
+fi
+
+
+
 { echo "$as_me:$LINENO: checking for SmcOpenConnection in -lSM" >&5
 echo $ECHO_N "checking for SmcOpenConnection in -lSM... $ECHO_C" >&6; }
 if test "${ac_cv_lib_SM_SmcOpenConnection+set}" = set; then

          

@@ 39,6 39,12 @@ AC_CHECK_LIB(Xpm, XpmCreatePixmapFromDat
     echo "Please either install the Xpm library and headers, or ensure you have CONFIG_USE_PIXMAPS set to False in Config.h"
     ])
 
+dnl Composite is necessary if CONFIG_USE_COMPOSITE
+AC_CHECK_LIB(Xcomposite, XCompositeQueryExtension, [], [
+    echo "Warning: Xcomposite library not found"
+    echo "Please either install the Xcomposite library and headers, or ensure you have CONFIG_USE_COMPOSITE set to False in Config.h"
+    ])
+
 dnl SM and ICE are necessary if CONFIG_USE_SESSION_MANAGER
 AC_CHECK_LIB(SM, SmcOpenConnection)
 AC_CHECK_LIB(ICE, IceConnectionNumber)