[gtk/global-coords] Fix the win32 build

[Matthias Clasen <matthiasc src gnome org>]

commit 6a40aa4fcd3cdbc1669ab32133104e2bbadd56f2
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed May 29 17:31:37 2019 +0000

    Fix the win32 build
    
    gdk_display_get_monitor_at_point was used
    in this backend.

 gdk/win32/gdksurface-win32.c | 71 +++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 70 insertions(+), 1 deletion(-)
---
diff --git a/gdk/win32/gdksurface-win32.c b/gdk/win32/gdksurface-win32.c
index 4336dcbbc7..eb51ce540d 100644
--- a/gdk/win32/gdksurface-win32.c
+++ b/gdk/win32/gdksurface-win32.c
@@ -3328,6 +3328,75 @@ update_fullup_indicator (GdkSurface                   *window,
   ensure_snap_indicator_surface (context, from_or_to.width, from_or_to.height, impl->surface_scale);
 }
 
+static GdkMonitor *
+get_monitor_at_point (GdkDisplay *display,
+                      int         x,
+                      int         y)
+{
+  GdkMonitor *nearest = NULL;
+  int nearest_dist = G_MAXINT;
+  int n_monitors, i;
+
+  n_monitors = gdk_display_get_n_monitors (display);
+  for (i = 0; i < n_monitors; i++)
+    {
+      GdkMonitor *monitor;
+      GdkRectangle geometry;
+      int dist_x, dist_y, dist;
+
+      monitor = gdk_display_get_monitor (display, i);
+      gdk_monitor_get_geometry (monitor, &geometry);
+
+      if (x < geometry.x)
+        dist_x = geometry.x - x;
+      else if (geometry.x + geometry.width <= x)
+        dist_x = x - (geometry.x + geometry.width) + 1;
+      else
+        dist_x = 0;
+
+      if (y < geometry.y)
+        dist_y = geometry.y - y;
+      else if (geometry.y + geometry.height <= y)
+        dist_y = y - (geometry.y + geometry.height) + 1;
+      else
+        dist_y = 0;
+
+      dist = dist_x + dist_y;
+      if (dist < nearest_dist)
+        {
+          nearest_dist = dist;
+          nearest = monitor;
+        }
+
+      if (x < geometry.x)
+      if (x < geometry.x)
+        dist_x = geometry.x - x;
+      else if (geometry.x + geometry.width <= x)
+        dist_x = x - (geometry.x + geometry.width) + 1;
+      else
+        dist_x = 0;
+
+      if (y < geometry.y)
+        dist_y = geometry.y - y;
+      else if (geometry.y + geometry.height <= y)
+        dist_y = y - (geometry.y + geometry.height) + 1;
+      else
+        dist_y = 0;
+
+      dist = dist_x + dist_y;
+      if (dist < nearest_dist)
+        {
+          nearest_dist = dist;
+          nearest = monitor;
+        }
+
+      if (nearest_dist == 0)
+        break;
+    }
+
+  return nearest;
+}
+
 static void
 start_indicator (GdkSurface                   *window,
                  GdkW32DragMoveResizeContext *context,
@@ -3343,7 +3412,7 @@ start_indicator (GdkSurface                   *window,
   GdkWin32Surface *impl = GDK_WIN32_SURFACE (window);
 
   display = gdk_surface_get_display (window);
-  monitor = gdk_display_get_monitor_at_point (display, x, y);
+  monitor = get_monitor_at_point (display, x, y);
   gdk_monitor_get_workarea (monitor, &workarea);
 
   maxysize = GetSystemMetrics (SM_CYVIRTUALSCREEN) / impl->surface_scale;