[gnome-panel/wip/geiger/geometry: 1/6] panel-struts: avoid GdkScreen API

[Sebastian Geiger <segeiger src gnome org>]

commit 080dcc2655ee9880b70ad506a76283347fe46a20
Author: Sebastian Geiger <sbastig gmx net>
Date:   Sun Feb 18 12:08:34 2018 +0100

    panel-struts: avoid GdkScreen API

 gnome-panel/panel-struts.c |   96 +++++++++++++++++++++++++++++++++++++++++---
 1 files changed, 90 insertions(+), 6 deletions(-)
---
diff --git a/gnome-panel/panel-struts.c b/gnome-panel/panel-struts.c
index 2bc4bda..af885a5 100644
--- a/gnome-panel/panel-struts.c
+++ b/gnome-panel/panel-struts.c
@@ -244,6 +244,91 @@ panel_struts_allocate_struts (PanelToplevel *toplevel,
        return toplevel_changed;
 }
 
+typedef struct {
+  int x0;
+  int y0;
+  int x1;
+  int y1;
+} MonitorBounds;
+
+static inline void
+get_monitor_bounds (GdkMonitor    *monitor,
+                   MonitorBounds *bounds)
+{
+       GdkRectangle geometry;
+
+       g_assert (bounds != NULL);
+
+       gdk_monitor_get_geometry (monitor,
+                                 &geometry);
+
+       bounds->x0 = geometry.x;
+       bounds->y0 = geometry.y;
+       bounds->x1 = bounds->x0 + geometry.width;
+       bounds->y1 = bounds->y0 + geometry.height;
+}
+
+/* Determines whether a given monitor is along the visible
+ * edge of the logical screen.
+ */
+static void
+find_logical_monitor_edges (GdkMonitor *monitor,
+                           gboolean   *leftmost,
+                           gboolean   *rightmost,
+                           gboolean   *topmost,
+                           gboolean   *bottommost)
+{
+       GdkDisplay *display;
+       MonitorBounds bounds = { 0 };
+       int i, n_monitors;
+
+       g_return_if_fail (monitor != NULL);
+
+       display = gdk_display_get_default ();
+
+       n_monitors = gdk_display_get_n_monitors (display);
+
+       *leftmost   = TRUE;
+       *rightmost  = TRUE;
+       *topmost    = TRUE;
+       *bottommost = TRUE;
+
+       get_monitor_bounds (monitor, &bounds);
+
+       /* go through each monitor and try to find one either right,
+        * below, above, or left of the specified monitor
+        */
+       for (i = 0; i < n_monitors; i++) {
+               MonitorBounds iter;
+               GdkMonitor *currentMonitor;
+
+               currentMonitor = gdk_display_get_monitor (display, i);
+
+               if (monitor == currentMonitor)
+                       continue;
+
+               get_monitor_bounds (currentMonitor, &iter);
+
+               if ((iter.y0 >= bounds.y0 && iter.y0 <  bounds.y1) ||
+                   (iter.y1 >  bounds.y0 && iter.y1 <= bounds.y1))
+               {
+                       if (iter.x0 < bounds.x0)
+                               *leftmost = FALSE;
+                       if (iter.x1 > bounds.x1)
+                               *rightmost = FALSE;
+               }
+
+               if ((iter.x0 >= bounds.x0 && iter.x0 <  bounds.x1) ||
+                   (iter.x1 >  bounds.x0 && iter.x1 <= bounds.x1))
+               {
+                       if (iter.y0 < bounds.y0)
+                               *topmost = FALSE;
+                       if (iter.y1 > bounds.y1)
+                               *bottommost = FALSE;
+               }
+       }
+}
+
 void
 panel_struts_set_window_hint (PanelToplevel *toplevel)
 {
@@ -276,12 +361,11 @@ panel_struts_set_window_hint (PanelToplevel *toplevel)
                                           &monitor_width,
                                           &monitor_height);
 
-        panel_multiscreen_is_at_visible_extreme (strut->screen,
-                                                 strut->monitor,
-                                                 &leftmost,
-                                                 &rightmost,
-                                                 &topmost,
-                                                 &bottommost);
+       find_logical_monitor_edges (strut->monitor,
+                                   &leftmost,
+                                   &rightmost,
+                                   &topmost,
+                                   &bottommost);
 
        switch (strut->orientation) {
        case PANEL_ORIENTATION_TOP: