Attempt to fix the visibility voodoo that doesn't account for mission…

… swapping

voodoo that is bad juju.

refs ticket:2265
refs ticket:2256

src/mission.c

@@ -303,8 +303,7 @@ BOOL missionShutDown(void)
 {
 	UDWORD		inc;
 
-	debug(LOG_SAVE, "called, mission is %s",
-	      missionIsOffworld() ? "off-world" : "main map");
+	debug(LOG_SAVE, "called, mission is %s", missionIsOffworld() ? "off-world" : "main map");
 	if (missionIsOffworld())
 	{
 		//clear out the audio
@@ -1366,7 +1365,8 @@ static void processMission(void)
 		psNext = psDroid->psNext;
 		//reset order - do this to all the droids that are returning from offWorld
 		orderDroid(psDroid, DORDER_STOP);
-
+		// clean up visibility 
+		visRemoveVisibility(psDroid);
 		//remove out of stored list and add to current Droid list
 		if (droidRemove(psDroid, apsDroidLists))
 		{
@@ -1446,6 +1446,8 @@ void processMissionLimbo(void)
 
 /*switch the pointers for the map and droid lists so that droid placement
  and orientation can occur on the map they will appear on*/
+// NOTE: This is one huge hack for campaign games!
+// Pay special attention on what is getting swapped!
 void swapMissionPointers(void)
 {
 	void		*pVoid;

src/visibility.c

@@ -277,7 +277,7 @@ BOOL visTilesPending(BASE_OBJECT *psObj)
 /* Remove tile visibility from object */
 void visRemoveVisibility(BASE_OBJECT *psObj)
 {
-	if (psObj->watchedTiles && psObj->numWatchedTiles > 0)
+	if (psObj->watchedTiles && psObj->numWatchedTiles > 0 && mapWidth && mapHeight)
 	{
 		int i = 0;
 
@@ -287,6 +287,11 @@ void visRemoveVisibility(BASE_OBJECT *psObj)
 			const TILEPOS pos = psObj->watchedTiles[i];
 			MAPTILE *psTile = mapTile(pos.x, pos.y);
 
+			// FIXME: the mapTile might have been swapped out, see swapMissionPointers()
+			if (psTile->watchers[psObj->player] == 0 && game.type == CAMPAIGN)
+			{
+				continue;
+			}
 			ASSERT(psTile->watchers[psObj->player] > 0, "Not watching watched tile (%d, %d)", (int)pos.x, (int)pos.y);
 			psTile->watchers[psObj->player]--;
 		}