Added another add_overlay() overload.

dlib/gui_widgets/widgets.h

@@ -3487,6 +3487,17 @@ namespace dlib
         void add_overlay(const rectangle& r, pixel_type p, const std::string& l) 
         { add_overlay(image_display::overlay_rect(r,p,l)); }
 
+        template <typename pixel_type>
+        void add_overlay(const std::vector<rectangle>& r, pixel_type p) 
+        { 
+            std::vector<overlay_rect> temp;
+            temp.resize(r.size());
+            for (unsigned long i = 0; i < temp.size(); ++i)
+                temp[i] = overlay_rect(r[i], p);
+
+            add_overlay(temp);
+        }
+
         void add_overlay (
             const overlay_line& overlay
         );

dlib/gui_widgets/widgets_abstract.h

@@ -2722,6 +2722,17 @@ namespace dlib
                 - performs: add_overlay(overlay_rect(r,p,l));
         !*/
 
+        template <typename pixel_type>
+        void add_overlay(
+            const std::vector<rectangle>& r,
+            pixel_type p
+        );
+        /*!
+            ensures
+                - adds the given set of rectangles into this object such
+                  that they will be displayed with the color specific by p. 
+        !*/
+
         void add_overlay (
             const overlay_line& overlay
         );