Fixed regression caused mercs not to be visible and commandable in undegrounds sectors.

git-svn-id: https://ja2svn.mooo.com/source/ja2/trunk/GameSource/ja2_v1.13/Build@9327 3b4a5df2-a311-0410-b5c6-a8a6f20db521

TileEngine/Isometric Utils.cpp

@@ -13,6 +13,7 @@
 #endif
 #include "Map Information.h"
 #include "meanwhile.h"
+#include "strategicmap.h"
 
 UINT32 guiForceRefreshMousePositionCalculation = 0;
 
@@ -1280,7 +1281,7 @@ INT16 MapY( INT32 sGridNo )
 
 bool GridNoOnWalkableWorldTile(INT32 sGridNo)
 {
-	if (AreInMeanwhile()) return true;
+	if (AreInMeanwhile() || gbWorldSectorZ != 0) return true;
 	//Shadooow: this will compare sGridNo height with height of the center grid of the map, as long as the center of the map is on a walkable height it will work properly
 	MAP_ELEMENT *pMapElement = &(gpWorldLevelData[sGridNo]);
 	MAP_ELEMENT *pMapElementCenter = &(gpWorldLevelData[gMapInformation.sCenterGridNo]);