[snappy] ui: fullscreen through X11 if available

[Luis de Bethencourt <luisbg src gnome org>]

commit 0d278ba37d9677c4f3e6c467cd176b25c0a15558
Author: Luis de Bethencourt <luis debethencourt com>
Date:   Sat May 12 11:24:15 2012 +0100

    ui: fullscreen through X11 if available
    
    Doing it this way makes the stage fullscreen in the current screen only instead
    of all across the desktop. So for multiscreen desktops it doesn't spread across
    multiple screens.

 src/user_interface.c |   66 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 66 insertions(+), 0 deletions(-)
---
diff --git a/src/user_interface.c b/src/user_interface.c
index 2037f7f..22895e9 100644
--- a/src/user_interface.c
+++ b/src/user_interface.c
@@ -27,6 +27,10 @@
 #include "user_interface.h"
 #include "utils.h"
 
+#ifdef CLUTTER_WINDOWING_X11
+#include <clutter/x11/clutter-x11.h>
+#endif
+
 // Declaration of static functions
 static gboolean controls_timeout_cb (gpointer data);
 static gboolean event_cb (ClutterStage * stage, ClutterEvent * event,
@@ -862,9 +866,70 @@ show_controls (UserInterface * ui, gboolean vis)
   }
 }
 
+#ifdef CLUTTER_WINDOWING_X11
+static void
+toggle_fullscreen_x11 (ClutterStage *stage,
+                       gboolean fullscreen)
+{
+  static gboolean is_fullscreen = FALSE;
+  static float old_width, old_height;
+
+  struct {
+    unsigned long flags;
+    unsigned long functions;
+    unsigned long decorations;
+    long inputMode;
+    unsigned long status;
+  } MWMHints = { 2, 0, 0, 0, 0};
+
+  Display *xdisplay = clutter_x11_get_default_display ();
+  int      xscreen  = clutter_x11_get_default_screen ();
+  Atom     wm_hints = XInternAtom(xdisplay, "_MOTIF_WM_HINTS", True);
+  Window   xwindow  = clutter_x11_get_stage_window (stage);
+
+  if (fullscreen)
+    {
+      int full_width = DisplayWidth (xdisplay, xscreen);
+      int full_height = DisplayHeight (xdisplay, xscreen)+5;
+        /* avoid being detected as fullscreen, workaround for some
+           windowmanagers  */
+      clutter_actor_get_size (CLUTTER_ACTOR (stage), &old_width, &old_height);
+
+      if (wm_hints != None)
+        XChangeProperty (xdisplay, xwindow, wm_hints, wm_hints, 32,
+                         PropModeReplace, (guchar*)&MWMHints,
+                         sizeof(MWMHints)/sizeof(long));
+      clutter_actor_set_size (CLUTTER_ACTOR (stage), full_width, full_height);
+      XMoveResizeWindow (xdisplay, xwindow,
+                         0, 0, full_width, full_height);
+    }
+  else
+    {
+      MWMHints.decorations = 7;
+      if (wm_hints != None )
+        XChangeProperty (xdisplay, xwindow, wm_hints, wm_hints, 32,
+                         PropModeReplace, (guchar*)&MWMHints,
+                         sizeof(MWMHints)/sizeof(long));
+      clutter_stage_set_fullscreen (stage, FALSE);
+      clutter_actor_set_size (CLUTTER_ACTOR (stage), old_width, old_height);
+    }
+}
+#endif
+
 static void
 toggle_fullscreen (UserInterface * ui)
 {
+#ifdef CLUTTER_WINDOWING_X11
+  if (clutter_check_windowing_backend (CLUTTER_WINDOWING_X11))
+    if (ui->fullscreen) {
+      toggle_fullscreen_x11 (CLUTTER_STAGE (ui->stage), FALSE);
+      ui->fullscreen = FALSE;
+    } else {
+      toggle_fullscreen_x11 (CLUTTER_STAGE (ui->stage), TRUE);
+      ui->fullscreen = TRUE;
+    }
+
+#else
   if (ui->fullscreen) {
     clutter_stage_set_fullscreen (CLUTTER_STAGE (ui->stage), FALSE);
     ui->fullscreen = FALSE;
@@ -872,6 +937,7 @@ toggle_fullscreen (UserInterface * ui)
     clutter_stage_set_fullscreen (CLUTTER_STAGE (ui->stage), TRUE);
     ui->fullscreen = TRUE;
   }
+#endif
 }
 
 static void