x11: use per-monitor work areaswip/muktupavels/work-areas-3-22

If window manager supports _NET_WORKAREA_Mn use per-monitor work
area.

3 files changed, 101 insertions, 11 deletions

diff --git a/gdk/x11/gdkmonitor-x11.c b/gdk/x11/gdkmonitor-x11.c
index 899511afcd..21a6da6fe9 100644
--- a/gdk/x11/gdkmonitor-x11.c
+++ b/gdk/x11/gdkmonitor-x11.c
@@ -66,18 +66,29 @@ gdk_x11_monitor_get_workarea (GdkMonitor   *monitor,
 
   gdk_monitor_get_geometry (monitor, dest);
 
-  /* The EWMH constrains workarea to be a rectangle, so it
-   * can't adequately deal with L-shaped monitor arrangements.
-   * As a workaround, we ignore the workarea for anything
-   * but the primary monitor. Since that is where the 'desktop
-   * chrome' usually lives, this works ok in practice.
-   */
-  if (gdk_monitor_is_primary (monitor) &&
-      !gdk_monitor_has_fullscreen_window (monitor))
+  if (_gdk_x11_screen_get_monitor_work_area (screen, monitor, &workarea))
     {
-      gdk_x11_screen_get_work_area (screen, &workarea);
-      if (gdk_rectangle_intersect (dest, &workarea, &workarea))
-        *dest = workarea;
+      if (!gdk_monitor_has_fullscreen_window (monitor))
+        {
+          if (gdk_rectangle_intersect (dest, &workarea, &workarea))
+            *dest = workarea;
+        }
+    }
+  else
+    {
+      /* The EWMH constrains workarea to be a rectangle, so it
+       * can't adequately deal with L-shaped monitor arrangements.
+       * As a workaround, we ignore the workarea for anything
+       * but the primary monitor. Since that is where the 'desktop
+       * chrome' usually lives, this works ok in practice.
+       */
+      if (gdk_monitor_is_primary (monitor) &&
+          !gdk_monitor_has_fullscreen_window (monitor))
+        {
+          gdk_x11_screen_get_work_area (screen, &workarea);
+          if (gdk_rectangle_intersect (dest, &workarea, &workarea))
+            *dest = workarea;
+        }
     }
 }
 
diff --git a/gdk/x11/gdkscreen-x11.c b/gdk/x11/gdkscreen-x11.c
index 43da96b45f..5ead4e129b 100644
--- a/gdk/x11/gdkscreen-x11.c
+++ b/gdk/x11/gdkscreen-x11.c
@@ -300,6 +300,82 @@ out:
   return FALSE;
 }
 
+static int
+get_monitor_num (GdkScreen  *screen,
+                 GdkMonitor *monitor)
+{
+#ifdef HAVE_XFREE_XINERAMA
+  GdkX11Screen *x11_screen = GDK_X11_SCREEN (screen);
+  XineramaScreenInfo *x_monitors;
+  int x_n_monitors;
+  GdkRectangle geometry;
+  int monitor_num;
+  int i;
+
+  if (!XineramaIsActive (x11_screen->xdisplay))
+    return -1;
+
+  x_monitors = XineramaQueryScreens (x11_screen->xdisplay, &x_n_monitors);
+  if (x_n_monitors <= 0 || x_monitors == NULL)
+    {
+      if (x_monitors)
+        XFree (x_monitors);
+
+      return -1;
+    }
+
+  gdk_monitor_get_geometry (monitor, &geometry);
+  monitor_num = -1;
+
+  for (i = 0; i < x_n_monitors; i++)
+    {
+      if (x_monitors[i].x_org != geometry.x ||
+          x_monitors[i].y_org != geometry.y ||
+          x_monitors[i].width != geometry.width ||
+          x_monitors[i].height != geometry.height)
+        continue;
+
+      monitor_num = i;
+      break;
+    }
+
+  XFree (x_monitors);
+  return monitor_num;
+#else
+  return -1;
+#endif
+}
+
+gboolean
+_gdk_x11_screen_get_monitor_work_area (GdkScreen    *screen,
+                                       GdkMonitor   *monitor,
+                                       GdkRectangle *area)
+{
+  Display *display;
+  int monitor_num;
+  gchar *workarea_name;
+  Atom workarea;
+
+  display = GDK_DISPLAY_XDISPLAY (gdk_screen_get_display (screen));
+
+  if (!gdk_x11_screen_supports_net_wm_hint (screen,
+                                            gdk_atom_intern_static_string ("_NET_WORKAREA_Mn")))
+    return FALSE;
+
+  monitor_num = get_monitor_num (screen, monitor);
+  if (monitor_num < 0)
+    return FALSE;
+
+  workarea_name = g_strdup_printf ("_NET_WORKAREA_M%d", monitor_num);
+  workarea = XInternAtom (display, workarea_name, True);
+  g_free (workarea_name);
+
+  if (workarea == None)
+    return FALSE;
+
+  return get_work_area (screen, workarea, area);
+}
+
 void
 gdk_x11_screen_get_work_area (GdkScreen    *screen,
                               GdkRectangle *area)
diff --git a/gdk/x11/gdkscreen-x11.h b/gdk/x11/gdkscreen-x11.h
index aca9b3c9e0..19edf2aa12 100644
--- a/gdk/x11/gdkscreen-x11.h
+++ b/gdk/x11/gdkscreen-x11.h
@@ -119,6 +119,9 @@ void _gdk_x11_screen_get_edge_monitors      (GdkScreen *screen,
 					     gint      *right);
 void _gdk_x11_screen_set_window_scale       (GdkX11Screen *x11_screen,
 					     int        scale);
+gboolean _gdk_x11_screen_get_monitor_work_area (GdkScreen    *screen,
+                                                GdkMonitor   *monitor,
+                                                GdkRectangle *area);
 void gdk_x11_screen_get_work_area           (GdkScreen    *screen,
                                              GdkRectangle *area);
 gint gdk_x11_screen_get_width               (GdkScreen *screen);