Display a icon into the movement hint where the unit can hide

(to replace the old sidebar use). Maybe later allow [hides] wml
ability to choose the icon.

src/game_display.cpp

@@ -675,6 +675,11 @@ void game_display::draw_movement_info(const gamemap::location& loc)
 			int xpos = get_location_x(loc);
 			int ypos = get_location_y(loc);
 
+            if (w->second.invisible) {
+				surface hidden_surf = image::get_image("misc/hidden.png", image::UNMASKED);
+				video().blit_surface(xpos, ypos, hidden_surf);
+			}
+
 			if (w->second.zoc) {
 				surface zoc_surf = image::get_image("misc/zoc.png", image::UNMASKED);
 				video().blit_surface(xpos, ypos, zoc_surf);

src/pathfind.cpp

@@ -254,7 +254,10 @@ int route_turns_to_complete(const unit& u, paths::route& rt, const team &viewing
 				 || (viewing_team.is_enemy(u.side()) && viewing_team.fogged(*i)) );
 
 			++turns;
-			rt.waypoints[*i] = paths::route::waypoint(turns, zoc, capture);
+
+			bool invisible = u.invisible(*i,units,teams,false);
+
+			rt.waypoints[*i] = paths::route::waypoint(turns, zoc, capture, invisible);
 			
 			if (last_step) break; // finished and we used dummy move_cost
 

src/pathfind.hpp

@@ -111,11 +111,14 @@ struct paths
 		int move_left; // movement unit will have left at end of the route.
 		struct waypoint
 		{
-			waypoint(int t = 0, bool z = false, bool c = false)
-				: turns(t), zoc(z), capture(c) {}
+			waypoint(int turns_number = 0, bool in_zoc = false,
+					bool do_capture = false, bool is_invisible = false)
+				: turns(turns_number), zoc(in_zoc),
+					capture(do_capture), invisible(is_invisible) {}
 			int turns;
 			bool zoc;
 			bool capture;
+			bool invisible;
 		};
 		std::map<gamemap::location, waypoint> waypoints;
 	};