Fix #6261: Broken pathfinding after removing park entrances with the tile inspector

Check the gParkEntrance locations after loading from file and clear those locations for which there is no longer a park entrance map element.
Resolves path finding problems in parks caused, for example, be deleting a park entrance using the tile inspector.

Fixes #6261, #6344, #6520.

distribution/changelog.txt

@@ -33,6 +33,7 @@
 - Fix: [#6196, #6223] Guest's energy underflows and never decreases.
 - Fix: [#6198] You cannot cancel RCT1 directory selection.
 - Fix: [#6202] Guests can break occupied benches (original bug).
+- Fix: [#6261, #6344, #6520] Broken pathfinding after removing park entrances with the tile inspector
 - Fix: [#6271] Wrong booster speed tooltip text.
 - Fix: [#6308] Cannot create title sequence if title sequences folder does not exist.
 - Fix: [#6318] Cannot sack staff that have not been placed

src/openrct2/game.c

@@ -1121,6 +1121,9 @@ void game_fix_save_vars()
 
     // Fix invalid vehicle sprite sizes, thus preventing visual corruption of sprites
     fix_invalid_vehicle_sprite_sizes();
+
+    // Fix gParkEntrance locations for which the map_element no longer exists
+    fix_park_entrance_locations();
 }
 
 void handle_park_load_failure_with_title_opt(const ParkLoadResult * result, const utf8 * path, bool loadTitleFirst)

src/openrct2/world/Entrance.cpp

@@ -683,4 +683,22 @@ extern "C"
             return;
         } while (!map_element_is_last_for_tile(mapElement++));
     }
+
+    void fix_park_entrance_locations(void)
+    {
+        // Fix gParkEntrance locations for which the map_element no longer exists
+        for (uint8 entranceNum = 0; entranceNum < MAX_PARK_ENTRANCES; ++entranceNum)
+        {
+            if (gParkEntrances[entranceNum].x == LOCATION_NULL)
+                continue;
+
+            if (map_get_park_entrance_element_at(
+                gParkEntrances[entranceNum].x,
+                gParkEntrances[entranceNum].y,
+                gParkEntrances[entranceNum].z >> 3, false) == NULL)
+            {
+                gParkEntrances[entranceNum].x = LOCATION_NULL;
+            }
+        }
+    }
 }

src/openrct2/world/entrance.h

@@ -58,6 +58,8 @@ void reset_park_entrance();
 void maze_entrance_hedge_replacement(sint32 x, sint32 y, rct_map_element *mapElement);
 void maze_entrance_hedge_removal(sint32 x, sint32 y, rct_map_element *mapElement);
 
+void fix_park_entrance_locations();
+
 #ifdef __cplusplus
 }
 #endif