diff --git a/src/action/command.cpp b/src/action/command.cpp
index baa7fc7b5..93eec05a7 100644
--- a/src/action/command.cpp
+++ b/src/action/command.cpp
@@ -851,22 +851,21 @@ void CommandSharedVision(int player, bool state, int opponent)
 
 	if (before && !after) {
 		// Don't share vision anymore. Give each other explored terrain for good-bye.
-		Vec2i pos;
-		for (pos.x = 0; pos.x < Map.Info.MapWidth; ++pos.x) {
-			for (pos.y = 0; pos.y < Map.Info.MapHeight; ++pos.y) {
-				CMapFieldPlayerInfo &mfp = Map.Field(pos)->playerInfo;
 
-				if (mfp.Visible[player] && !mfp.Visible[opponent]) {
-					mfp.Visible[opponent] = 1;
-					if (opponent == ThisPlayer->Index) {
-						Map.MarkSeenTile(pos);
-					}
+		for (int i = 0; i != this->Info.MapWidth * this->Info.MapHeight; ++i) {
+			CMapField &mf = *this->Field(i);
+			CMapFieldPlayerInfo &mfp = mf.playerInfo;
+
+			if (mfp.Visible[player] && !mfp.Visible[opponent]) {
+				mfp.Visible[opponent] = 1;
+				if (opponent == ThisPlayer->Index) {
+					Map.MarkSeenTile(mf);
 				}
-				if (mfp.Visible[opponent] && !mfp.Visible[player]) {
-					mfp.Visible[player] = 1;
-					if (player == ThisPlayer->Index) {
-						Map.MarkSeenTile(pos);
-					}
+			}
+			if (mfp.Visible[opponent] && !mfp.Visible[player]) {
+				mfp.Visible[player] = 1;
+				if (player == ThisPlayer->Index) {
+					Map.MarkSeenTile(mf);
 				}
 			}
 		}
diff --git a/src/include/map.h b/src/include/map.h
index ad241e194..ed8112b6c 100644
--- a/src/include/map.h
+++ b/src/include/map.h
@@ -187,13 +187,7 @@ public:
 	PixelPos TilePosToMapPixelPos_Center(const Vec2i &tilePos) const;
 
 	/// Mark a tile as seen by the player.
-	void MarkSeenTile(const unsigned int index);
-
-	/// Mark a tile as seen by the player.
-	void MarkSeenTile(const Vec2i &pos) {
-		Assert(Info.IsPointOnMap(pos));
-		MarkSeenTile(getIndex(pos));
-	}
+	void MarkSeenTile(CMapField &mf);
 
 	/// Regenerate the forest.
 	void RegenerateForest();
diff --git a/src/map/map.cpp b/src/map/map.cpp
index 2d2a227b7..e33f394e9 100644
--- a/src/map/map.cpp
+++ b/src/map/map.cpp
@@ -64,9 +64,8 @@ char CurrentMapPath[1024];       /// Path of the current map
 **  @param x  Map X tile-position.
 **  @param y  Map Y tile-position.
 */
-void CMap::MarkSeenTile(const unsigned int index)
+void CMap::MarkSeenTile(CMapField &mf)
 {
-	CMapField &mf = *this->Field(index);
 	const int tile = mf.Tile;
 	const int seentile = mf.playerInfo.SeenTile;
 
@@ -80,6 +79,7 @@ void CMap::MarkSeenTile(const unsigned int index)
 
 #ifdef MINIMAP_UPDATE
 	//rb - GRRRRRRRRRRRR
+	const unsigned int index = &mf - Map.Fields;
 	const int y = index / Info.MapWidth;
 	const int x = index - (y * Info.MapWidth);
 	const Vec2i pos = {x, y}
@@ -88,6 +88,7 @@ void CMap::MarkSeenTile(const unsigned int index)
 	if (this->Tileset.TileTypeTable) {
 #ifndef MINIMAP_UPDATE
 		//rb - GRRRRRRRRRRRR
+		const unsigned int index = &mf - Map.Fields;
 		const int y = index / Info.MapWidth;
 		const int x = index - (y * Info.MapWidth);
 		const Vec2i pos(x, y);
@@ -132,15 +133,13 @@ void CMap::MarkSeenTile(const unsigned int index)
 void CMap::Reveal()
 {
 	//  Mark every explored tile as visible. 1 turns into 2.
-	Vec2i pos;
-	for (pos.x = 0; pos.x < this->Info.MapWidth; ++pos.x) {
-		for (pos.y = 0; pos.y < this->Info.MapHeight; ++pos.y) {
-			CMapFieldPlayerInfo &playerInfo = this->Field(pos)->playerInfo;
-			for (int p = 0; p < PlayerMax; ++p) {
-				playerInfo.Visible[p] = std::max<unsigned short>(1, playerInfo.Visible[p]);
-			}
-			MarkSeenTile(pos);
+	for (int i = 0; i != this->Info.MapWidth * this->Info.MapHeight; ++i) {
+		CMapField &mf = *this->Field(i);
+		CMapFieldPlayerInfo &playerInfo = mf.playerInfo;
+		for (int p = 0; p < PlayerMax; ++p) {
+			playerInfo.Visible[p] = std::max<unsigned short>(1, playerInfo.Visible[p]);
 		}
+		MarkSeenTile(mf);
 	}
 	//  Global seen recount. Simple and effective.
 	for (CUnitManager::Iterator it = UnitManager.begin(); it != UnitManager.end(); ++it) {
@@ -428,11 +427,11 @@ void CMap::FixTile(unsigned short type, int seen, const Vec2i &pos)
 		return;
 	}
 	unsigned int index = getIndex(pos);
-	CMapField *mf = this->Field(index);
+	CMapField &mf = *this->Field(index);
 
-	if (seen && !Tileset.IsSeenTile(type, mf->playerInfo.SeenTile)) {
+	if (seen && !Tileset.IsSeenTile(type, mf.playerInfo.SeenTile)) {
 		return;
-	} else if (!seen && !(mf->Flags & type)) {
+	} else if (!seen && !(mf.Flags & type)) {
 		return;
 	}
 
@@ -468,41 +467,41 @@ void CMap::FixTile(unsigned short type, int seen, const Vec2i &pos)
 	if (pos.y - 1 < 0) {
 		ttup = 15; //Assign trees in all directions
 	} else {
-		CMapField *new_mf = (mf - this->Info.MapWidth);
+		CMapField &new_mf = *(&mf - this->Info.MapWidth);
 		if (seen) {
-			ttup = this->Tileset.MixedLookupTable[new_mf->playerInfo.SeenTile];
+			ttup = this->Tileset.MixedLookupTable[new_mf.playerInfo.SeenTile];
 		} else {
-			ttup = this->Tileset.MixedLookupTable[new_mf->Tile];
+			ttup = this->Tileset.MixedLookupTable[new_mf.Tile];
 		}
 	}
 	if (pos.x + 1 >= this->Info.MapWidth) {
 		ttright = 15; //Assign trees in all directions
 	} else {
-		CMapField *new_mf = (mf + 1);
+		CMapField &new_mf = *(&mf + 1);
 		if (seen) {
-			ttright = this->Tileset.MixedLookupTable[new_mf->playerInfo.SeenTile];
+			ttright = this->Tileset.MixedLookupTable[new_mf.playerInfo.SeenTile];
 		} else {
-			ttright = this->Tileset.MixedLookupTable[new_mf->Tile];
+			ttright = this->Tileset.MixedLookupTable[new_mf.Tile];
 		}
 	}
 	if (pos.y + 1 >= this->Info.MapHeight) {
 		ttdown = 15; //Assign trees in all directions
 	} else {
-		CMapField *new_mf = (mf + this->Info.MapWidth);
+		CMapField &new_mf = *(&mf + this->Info.MapWidth);
 		if (seen) {
-			ttdown = this->Tileset.MixedLookupTable[new_mf->playerInfo.SeenTile];
+			ttdown = this->Tileset.MixedLookupTable[new_mf.playerInfo.SeenTile];
 		} else {
-			ttdown = this->Tileset.MixedLookupTable[new_mf->Tile];
+			ttdown = this->Tileset.MixedLookupTable[new_mf.Tile];
 		}
 	}
 	if (pos.x - 1 < 0) {
 		ttleft = 15; //Assign trees in all directions
 	} else {
-		CMapField *new_mf = (mf - 1);
+		CMapField &new_mf = *(&mf - 1);
 		if (seen) {
-			ttleft = this->Tileset.MixedLookupTable[new_mf->playerInfo.SeenTile];
+			ttleft = this->Tileset.MixedLookupTable[new_mf.playerInfo.SeenTile];
 		} else {
-			ttleft = this->Tileset.MixedLookupTable[new_mf->Tile];
+			ttleft = this->Tileset.MixedLookupTable[new_mf.Tile];
 		}
 	}
 
@@ -545,30 +544,30 @@ void CMap::FixTile(unsigned short type, int seen, const Vec2i &pos)
 	//Update seen tile.
 	if (tile == -1) { // No valid wood remove it.
 		if (seen) {
-			mf->playerInfo.SeenTile = removedtile;
+			mf.playerInfo.SeenTile = removedtile;
 			this->FixNeighbors(type, seen, pos);
 		} else {
-			mf->Tile = removedtile;
-			mf->Flags &= ~flags;
-			mf->Value = 0;
+			mf.Tile = removedtile;
+			mf.Flags &= ~flags;
+			mf.Value = 0;
 			UI.Minimap.UpdateXY(pos);
 		}
-	} else if (seen && this->Tileset.MixedLookupTable[mf->playerInfo.SeenTile] ==
+	} else if (seen && this->Tileset.MixedLookupTable[mf.playerInfo.SeenTile] ==
 			   this->Tileset.MixedLookupTable[tile]) { //Same Type
 		return;
 	} else {
 		if (seen) {
-			mf->playerInfo.SeenTile = tile;
+			mf.playerInfo.SeenTile = tile;
 		} else {
-			mf->Tile = tile;
+			mf.Tile = tile;
 		}
 	}
 
 	//maybe isExplored
-	if (mf->playerInfo.IsExplored(*ThisPlayer)) {
+	if (mf.playerInfo.IsExplored(*ThisPlayer)) {
 		UI.Minimap.UpdateSeenXY(pos);
 		if (!seen) {
-			MarkSeenTile(pos);
+			MarkSeenTile(mf);
 		}
 	}
 }
@@ -627,7 +626,7 @@ void CMap::ClearTile(unsigned short type, const Vec2i &pos)
 	//maybe isExplored
 	if (mf.playerInfo.IsExplored(*ThisPlayer)) {
 		UI.Minimap.UpdateSeenXY(pos);
-		MarkSeenTile(pos);
+		MarkSeenTile(mf);
 	}
 }
 
@@ -672,11 +671,11 @@ void CMap::RegenerateForestTile(const Vec2i &pos)
 		mf.Value = 0;
 		mf.Flags |= MapFieldForest | MapFieldUnpassable;
 		if (mf.playerInfo.IsTeamVisible(*ThisPlayer)) {
-			MarkSeenTile(pos);
+			MarkSeenTile(mf);
 		}
 		const Vec2i offset(0, -1);
 		if (Map.Field(pos + offset)->playerInfo.IsTeamVisible(*ThisPlayer)) {
-			MarkSeenTile(pos);
+			MarkSeenTile(mf);
 		}
 	}
 }
diff --git a/src/map/map_fog.cpp b/src/map/map_fog.cpp
index 2b2819c5c..b6eb42af9 100644
--- a/src/map/map_fog.cpp
+++ b/src/map/map_fog.cpp
@@ -229,7 +229,7 @@ void MapMarkTileSight(const CPlayer &player, const unsigned int index)
 		}
 		*v = 2;
 		if (mf.playerInfo.IsTeamVisible(*ThisPlayer)) {
-			Map.MarkSeenTile(index);
+			Map.MarkSeenTile(mf);
 		}
 		return;
 	}
@@ -267,7 +267,7 @@ void MapUnmarkTileSight(const CPlayer &player, const unsigned int index)
 			}
 			// Check visible Tile, then deduct...
 			if (mf.playerInfo.IsTeamVisible(*ThisPlayer)) {
-				Map.MarkSeenTile(index);
+				Map.MarkSeenTile(mf);
 			}
 		default:  // seen -> seen
 			--*v;
@@ -407,20 +407,17 @@ void MapSight(const CPlayer &player, const Vec2i &pos, int w, int h, int range,
 void UpdateFogOfWarChange()
 {
 	DebugPrint("::UpdateFogOfWarChange\n");
-	//
 	//  Mark all explored fields as visible again.
-	//
 	if (Map.NoFogOfWar) {
 		const unsigned int w = Map.Info.MapHeight * Map.Info.MapWidth;
 		for (unsigned int index = 0; index != w; ++index) {
-			if (Map.Field(index)->playerInfo.IsExplored(*ThisPlayer)) {
-				Map.MarkSeenTile(index);
+			CMapField &mf = *Map.Field(index);
+			if (mf.playerInfo.IsExplored(*ThisPlayer)) {
+				Map.MarkSeenTile(mf);
 			}
 		}
 	}
-	//
 	//  Global seen recount.
-	//
 	for (CUnitManager::Iterator it = UnitManager.begin(); it != UnitManager.end(); ++it) {
 		CUnit &unit = **it;
 		UnitCountSeen(unit);
diff --git a/src/map/map_wall.cpp b/src/map/map_wall.cpp
index d88c7dbef..3b194c90a 100644
--- a/src/map/map_wall.cpp
+++ b/src/map/map_wall.cpp
@@ -249,7 +249,7 @@ void MapFixWallTile(const Vec2i &pos)
 
 		if (mf.playerInfo.IsTeamVisible(*ThisPlayer)) {
 			UI.Minimap.UpdateSeenXY(pos);
-			Map.MarkSeenTile(pos);
+			Map.MarkSeenTile(mf);
 		}
 	}
 }
@@ -287,7 +287,7 @@ void CMap::RemoveWall(const Vec2i &pos)
 
 	if (mf.playerInfo.IsTeamVisible(*ThisPlayer)) {
 		UI.Minimap.UpdateSeenXY(pos);
-		this->MarkSeenTile(pos);
+		this->MarkSeenTile(mf);
 	}
 }
 
@@ -322,7 +322,7 @@ void CMap::SetWall(const Vec2i &pos, int humanwall)
 
 	if (mf.playerInfo.IsTeamVisible(*ThisPlayer)) {
 		UI.Minimap.UpdateSeenXY(pos);
-		this->MarkSeenTile(pos);
+		this->MarkSeenTile(mf);
 	}
 }