Account for xinerama layout when calculating struts. This is an attempt to fix bug #1316.

(Old svn revision: 19748)

panel/panel-app.c

@@ -301,7 +301,7 @@ create_monitor_list (void)
 
         for (j = 0; j < n_monitors; ++j)
         {
-            monitor = g_new (XfceMonitor, 1);
+            monitor = g_new0 (XfceMonitor, 1);
 
             monitor->screen = screen;
             monitor->num = j;
@@ -322,7 +322,7 @@ create_monitor_list (void)
             h = monitor->geometry.height;
             
 #if TEST_MULTIPLE_MONITORS
-            monitor = g_new (XfceMonitor, 1);
+            monitor = g_new0 (XfceMonitor, 1);
 
             monitor->screen = screen;
             monitor->num = j;
@@ -342,6 +342,55 @@ create_monitor_list (void)
         panel_app.xinerama_and_equal_width = equal_w;
         panel_app.xinerama_and_equal_height = equal_h;
     }
+
+    /* check layout */
+    /* TODO: can this be optimized? does it need to be? */
+    for (i = 0; i < panel_app.monitor_list->len; ++i)
+    {
+        XfceMonitor *mon1 = g_ptr_array_index (panel_app.monitor_list, i);
+        
+        for (j = 0; j < panel_app.monitor_list->len; ++j)
+        {
+            XfceMonitor *mon2;
+            
+            if (j == i)
+                continue;
+
+            mon2 = g_ptr_array_index (panel_app.monitor_list, j);
+
+            if (mon2->geometry.x < mon1->geometry.x
+                && mon2->geometry.y < mon1->geometry.y + mon1->geometry.height
+                && mon2->geometry.y + mon2->geometry.height > mon1->geometry.y
+               )
+            {
+                mon1->has_neighbor_left = TRUE;
+            }
+
+            if (mon2->geometry.x > mon1->geometry.x
+                && mon2->geometry.y < mon1->geometry.y + mon1->geometry.height
+                && mon2->geometry.y + mon2->geometry.height > mon1->geometry.y
+               )
+            {
+                mon1->has_neighbor_right = TRUE;
+            }
+
+            if (mon2->geometry.y < mon1->geometry.y
+                && mon2->geometry.x < mon1->geometry.x + mon1->geometry.width
+                && mon2->geometry.x + mon2->geometry.width > mon1->geometry.x
+               )
+            {
+                mon1->has_neighbor_above = TRUE;
+            }
+
+            if (mon2->geometry.y > mon1->geometry.y
+                && mon2->geometry.x < mon1->geometry.x + mon1->geometry.width
+                && mon2->geometry.x + mon2->geometry.width > mon1->geometry.x
+               )
+            {
+                mon1->has_neighbor_below = TRUE;
+            }
+        }
+    }
 }
 
 /* open dialogs */

panel/panel-app.h

@@ -34,6 +34,10 @@ struct _XfceMonitor
     GdkScreen *screen;
     int num;
     GdkRectangle geometry;
+    guint has_neighbor_left:1;
+    guint has_neighbor_right:1;
+    guint has_neighbor_above:1;
+    guint has_neighbor_below:1;
 };
 
 /* run control */

panel/panel-properties.c

@@ -230,7 +230,7 @@ _set_borders (Panel *panel)
 }
 
 static void
-_set_struts (Panel *panel, int x, int y, int w, int h)
+_set_struts (Panel *panel, XfceMonitor *xmon, int x, int y, int w, int h)
 {
     PanelPrivate *priv;
     gulong data[12] = { 0, };
@@ -242,31 +242,57 @@ _set_struts (Panel *panel, int x, int y, int w, int h)
     {
         if (xfce_screen_position_is_left (priv->screen_position))
         {
-            data[0] = w;	/* left           */
-
-            data[4] = y;	/* left_start_y   */
-            data[5] = y + h;	/* left_end_y     */
+            /* no struts possible on Xinerama screens when this is monitor
+             * has neighbors on the left (see fd.o spec).
+             */
+            if (!xmon->has_neighbor_left)
+            {
+                data[0] = xmon->geometry.x 
+                          + w;          /* left           */
+                data[4] = y;	        /* left_start_y   */
+                data[5] = y + h;	/* left_end_y     */
+            }
         }
         else if (xfce_screen_position_is_right (priv->screen_position))
         {
-            data[1] = w;	/* right          */
-
-            data[6] = y;	/* right_start_y  */
-            data[7] = y + h;	/* right_end_y    */
+            /* no struts possible on Xinerama screens when this is monitor
+             * has neighbors on the right (see fd.o spec).
+             */
+            if (!xmon->has_neighbor_right)
+            {
+                data[1] =  gdk_screen_get_width (xmon->screen) 
+                           - xmon->geometry.x - xmon->geometry.width 
+                           + w;         /* right          */
+                data[6] = y;	        /* right_start_y  */
+                data[7] = y + h;	/* right_end_y    */
+            }
         }
         else if (xfce_screen_position_is_top (priv->screen_position))
         {
-            data[2] = h;	/* top            */
-
-            data[8] = x;	/* top_start_x    */
-            data[9] = x + w;	/* top_end_x      */
+            /* no struts possible on Xinerama screens when this is monitor
+             * has neighbors on the top (see fd.o spec).
+             */
+            if (!xmon->has_neighbor_above)
+            {
+                data[2] = xmon->geometry.y 
+                          + h;	        /* top            */
+                data[8] = x;	        /* top_start_x    */
+                data[9] = x + w;	/* top_end_x      */
+            }
         }
         else
         {
-            data[3] = h;	/* bottom         */
-
-            data[10] = x;	/* bottom_start_x */
-            data[11] = x + w;	/* bottom_end_x   */
+            /* no struts possible on Xinerama screens when this is monitor
+             * has neighbors on the bottom (see fd.o spec).
+             */
+            if (!xmon->has_neighbor_below)
+            {
+                data[3] = gdk_screen_get_width (xmon->screen) 
+                           - xmon->geometry.x - xmon->geometry.width 
+                           + h;	        /* bottom         */
+                data[10] = x;	        /* bottom_start_x */
+                data[11] = x + w;	/* bottom_end_x   */
+            }
 	}
     }
 
@@ -350,7 +376,7 @@ panel_resize_function (XfcePanelWindow *window, Panel *panel,
     DBG ("\n + Position: %d\n + Offset: (%d, %d)", 
          priv->screen_position, priv->xoffset, priv->yoffset);
 
-    _set_struts (panel, *x, *y, new->width, new->height);
+    _set_struts (panel, xmon, *x, *y, new->width, new->height);
 }
 
 static void 
@@ -412,7 +438,7 @@ panel_set_position (Panel *panel, XfceScreenPosition position,
     
     gtk_window_move (GTK_WINDOW (panel), x, y);
 
-    _set_struts (panel, x, y, req.width, req.height);
+    _set_struts (panel, xmon, x, y, req.width, req.height);
 }
 
 /* screen size */