(svn r1749) Move the functions which calculate distances to map.[ch] and give the more meaningful names

18 files changed, 122 insertions, 102 deletions

diff --git a/ai.c b/ai.c
index ed5df3334..b04c692d4 100644
--- a/ai.c
+++ b/ai.c
@@ -462,7 +462,7 @@ static void AiFindSubsidyIndustryRoute(FoundRoute *fr)
 		to_xy = to_ind->xy;
 	}
 
-	fr->distance = GetTileDist(from->xy, to_xy);
+	fr->distance = DistanceManhattan(from->xy, to_xy);
 }
 
 static void AiFindSubsidyPassengerRoute(FoundRoute *fr)
@@ -493,7 +493,7 @@ static void AiFindSubsidyPassengerRoute(FoundRoute *fr)
 	if (from->population < 400 || to->population < 400)
 		return;
 
-	fr->distance = GetTileDist(from->xy, to->xy);
+	fr->distance = DistanceManhattan(from->xy, to->xy);
 }
 
 static void AiFindRandomIndustryRoute(FoundRoute *fr)
@@ -531,7 +531,7 @@ static void AiFindRandomIndustryRoute(FoundRoute *fr)
 			return;
 
 		fr->to = i2;
-		fr->distance = GetTileDist(i->xy, i2->xy);
+		fr->distance = DistanceManhattan(i->xy, i2->xy);
 	} else {
 		// pick a dest town, and see if it's big enough
 		t = AiFindRandomTown();
@@ -539,7 +539,7 @@ static void AiFindRandomIndustryRoute(FoundRoute *fr)
 			return;
 
 		fr->to = t;
-		fr->distance = GetTileDist(i->xy, t->xy);
+		fr->distance = DistanceManhattan(i->xy, t->xy);
 	}
 }
 
@@ -561,7 +561,7 @@ static void AiFindRandomPassengerRoute(FoundRoute *fr)
 	if (dest == NULL || source == dest || dest->population < 400)
 		return;
 
-	fr->distance = GetTileDist(source->xy, dest->xy);
+	fr->distance = DistanceManhattan(source->xy, dest->xy);
 }
 
 // Warn: depends on 'xy' being the first element in both Town and Industry
@@ -580,9 +580,9 @@ static bool AiCheckIfRouteIsGood(Player *p, FoundRoute *fr, byte bitmask)
 
 	dist = 0xFFFF;
 	FOR_ALL_STATIONS(st) if (st->xy != 0 && st->owner == _current_player) {
-		cur = GetTileDist1D(from_tile, st->xy);
+		cur = DistanceMax(from_tile, st->xy);
 		if (cur < dist) dist = cur;
-		cur = GetTileDist1D(to_tile, st->xy);
+		cur = DistanceMax(to_tile, st->xy);
 		if (cur < dist) dist = cur;
 		if (to_tile == from_tile && st->xy == to_tile)
 		    same_station++;
@@ -1419,7 +1419,7 @@ static void AiWantOilRigAircraftRoute(Player *p)
 			// Find a random oil rig industry
 			in = GetIndustry(RandomRange(_total_industries));
 			if (in != NULL && in->type == IT_OIL_RIG) {
-				if (GetTileDist(t->xy, in->xy) < 60)
+				if (DistanceManhattan(t->xy, in->xy) < 60)
 					break;
 			}
 		}
@@ -1843,7 +1843,7 @@ static bool AiEnumFollowTrack(uint tile, AiRailPathFindData *a, int track, uint
 		return true;
 	}
 
-	if (GetTileDist1D(tile, a->tile2) < 4)
+	if (DistanceMax(tile, a->tile2) < 4)
 		a->count++;
 
 	return false;
@@ -2028,7 +2028,7 @@ static void AiBuildRailRecursive(AiRailFinder *arf, TileIndex tile, int dir)
 
 	// Depth too deep?
 	if (arf->depth >= 4) {
-		uint dist = GetTileDist1Db(tile, arf->final_tile);
+		uint dist = DistanceMaxPlusManhattan(tile, arf->final_tile);
 		if (dist < arf->cur_best_dist) {
 			// Store the tile that is closest to the final position.
 			arf->cur_best_depth = arf->depth;
@@ -2620,7 +2620,7 @@ static bool AiCheckBlockDistances(Player *p, TileIndex tile)
 
 	do {
 		if (aib->cur_building_rule != 255) {
-			if (GetTileDist(aib->use_tile, tile) < 9)
+			if (DistanceManhattan(aib->use_tile, tile) < 9)
 				return false;
 		}
 	} while (++aib, --num);
@@ -2768,7 +2768,7 @@ static bool AiCheckRoadPathBetter(AiRoadFinder *arf, const byte *p)
 
 static bool AiEnumFollowRoad(uint tile, AiRoadEnum *a, int track, uint length, byte *state)
 {
-	uint dist = GetTileDist(tile, a->dest);
+	uint dist = DistanceManhattan(tile, a->dest);
 	uint tile2;
 
 	if (dist <= a->best_dist) {
@@ -2813,7 +2813,7 @@ static bool AiCheckRoadFinished(Player *p)
 		FollowTrack(tile, 0x3000 | TRANSPORT_ROAD, _dir_by_track[i], (TPFEnumProc*)AiEnumFollowRoad, NULL, &are);
 	}
 
-	if (GetTileDist(tile, are.dest) <= are.best_dist)
+	if (DistanceManhattan(tile, are.dest) <= are.best_dist)
 		return false;
 
 	if (are.best_dist == 0)
@@ -2913,7 +2913,7 @@ static void AiBuildRoadRecursive(AiRoadFinder *arf, TileIndex tile, int dir)
 
 	// Depth too deep?
 	if (arf->depth >= 4) {
-		uint dist = GetTileDist1Db(tile, arf->final_tile);
+		uint dist = DistanceMaxPlusManhattan(tile, arf->final_tile);
 		if (dist < arf->cur_best_dist) {
 			// Store the tile that is closest to the final position.
 			arf->cur_best_dist = dist;
@@ -3292,7 +3292,7 @@ static void AiStateAirportStuff(Player *p)
 				continue;
 
 			// Dismiss airports too far away.
-			if (GetTileDist1D(st->airport_tile, aib->spec_tile) > aib->rand_rng)
+			if (DistanceMax(st->airport_tile, aib->spec_tile) > aib->rand_rng)
 				continue;
 
 			// It's ideal airport, let's take it!
diff --git a/ai_new.c b/ai_new.c
index 1699f7a4a..ccaffd124 100644
--- a/ai_new.c
+++ b/ai_new.c
@@ -224,7 +224,7 @@ static bool AiNew_Check_City_or_Industry(Player *p, int ic, byte type) {
 				//  to build there
 				if (!st->goods[CT_PASSENGERS].last_speed) continue;
 				// Is it around our city
-				if (GetTileDist(st->xy, t->xy) > 10) continue;
+				if (DistanceManhattan(st->xy, t->xy) > 10) continue;
 				// It does take this cargo.. what is his rating?
 				if (st->goods[CT_PASSENGERS].rating < AI_CHECKCITY_CARGO_RATING) continue;
 				j++;
@@ -287,7 +287,7 @@ static bool AiNew_Check_City_or_Industry(Player *p, int ic, byte type) {
 				// It does not take this cargo
 				if (!st->goods[i->produced_cargo[0]].last_speed) continue;
 				// Is it around our industry
-				if (GetTileDist(st->xy, i->xy) > 5) continue;
+				if (DistanceManhattan(st->xy, i->xy) > 5) continue;
 				// It does take this cargo.. what is his rating?
 				if (st->goods[i->produced_cargo[0]].rating < AI_CHECKCITY_CARGO_RATING) continue;
 				j++;
@@ -410,12 +410,17 @@ static void AiNew_State_LocateRoute(Player *p) {
    			max_cargo -= GetTown(p->ainew.from_ic)->act_pass + GetTown(p->ainew.temp)->act_pass;
    			// max_cargo is now the amount of cargo we can move between the two cities
    			// If it is more than the distance, we allow it
-   			if (GetTileDist(GetTown(p->ainew.from_ic)->xy, GetTown(p->ainew.temp)->xy) <= max_cargo * AI_LOCATEROUTE_BUS_CARGO_DISTANCE) {
+   			if (DistanceManhattan(GetTown(p->ainew.from_ic)->xy, GetTown(p->ainew.temp)->xy) <= max_cargo * AI_LOCATEROUTE_BUS_CARGO_DISTANCE) {
    				// We found a good city/industry, save the data of it
    				p->ainew.to_ic = p->ainew.temp;
    				p->ainew.state = AI_STATE_FIND_STATION;
 
-   				DEBUG(ai,1)("[AiNew - LocateRoute] Found bus-route of %d tiles long (from %d to %d)",GetTileDist(GetTown(p->ainew.from_ic)->xy, GetTown(p->ainew.temp)->xy), p->ainew.from_ic, p->ainew.temp);
+   				DEBUG(ai,1)(
+						"[AiNew - LocateRoute] Found bus-route of %d tiles long (from %d to %d)",
+						DistanceManhattan(GetTown(p->ainew.from_ic)->xy, GetTown(p->ainew.temp)->xy),
+						p->ainew.from_ic,
+						p->ainew.temp
+					);
 
    				p->ainew.from_tile = 0;
    				p->ainew.to_tile = 0;
@@ -458,8 +463,8 @@ static void AiNew_State_LocateRoute(Player *p) {
    			if (found) {
    				// Yeah, they are compatible!!!
    				// Check the length against the amount of goods
-   				if (GetTileDist(GetIndustry(p->ainew.from_ic)->xy, GetIndustry(p->ainew.temp)->xy) > AI_LOCATEROUTE_TRUCK_MIN_DISTANCE &&
-       				GetTileDist(GetIndustry(p->ainew.from_ic)->xy, GetIndustry(p->ainew.temp)->xy) <= max_cargo * AI_LOCATEROUTE_TRUCK_CARGO_DISTANCE) {
+   				if (DistanceManhattan(GetIndustry(p->ainew.from_ic)->xy, GetIndustry(p->ainew.temp)->xy) > AI_LOCATEROUTE_TRUCK_MIN_DISTANCE &&
+       				DistanceManhattan(GetIndustry(p->ainew.from_ic)->xy, GetIndustry(p->ainew.temp)->xy) <= max_cargo * AI_LOCATEROUTE_TRUCK_CARGO_DISTANCE) {
 	   				p->ainew.to_ic = p->ainew.temp;
 	   				if (p->ainew.from_deliver) {
 	   					p->ainew.cargo = GetIndustry(p->ainew.from_ic)->produced_cargo[0];
@@ -468,7 +473,12 @@ static void AiNew_State_LocateRoute(Player *p) {
    					}
 	   				p->ainew.state = AI_STATE_FIND_STATION;
 
-	   				DEBUG(ai,1)("[AiNew - LocateRoute] Found truck-route of %d tiles long (from %d to %d)",GetTileDist(GetIndustry(p->ainew.from_ic)->xy, GetIndustry(p->ainew.temp)->xy), p->ainew.from_ic, p->ainew.temp);
+	   				DEBUG(ai,1)(
+							"[AiNew - LocateRoute] Found truck-route of %d tiles long (from %d to %d)",
+							DistanceManhattan(GetIndustry(p->ainew.from_ic)->xy, GetIndustry(p->ainew.temp)->xy),
+							p->ainew.from_ic,
+							p->ainew.temp
+						);
 
 	   				p->ainew.from_tile = 0;
 	   				p->ainew.to_tile = 0;
@@ -637,7 +647,7 @@ static void AiNew_State_FindStation(Player *p) {
 
 	    for (x=0;x<i;x++) {
 	    	if (found_best[x] > best ||
-	     		(found_best[x] == best && GetTileDist(tile, new_tile) > GetTileDist(tile, found_spot[x]))) {
+	     		(found_best[x] == best && DistanceManhattan(tile, new_tile) > DistanceManhattan(tile, found_spot[x]))) {
 	     		new_tile = found_spot[x];
 	     		best = found_best[x];
 	    	}
diff --git a/ai_pathfinder.c b/ai_pathfinder.c
index 4510c60f4..6266352dd 100644
--- a/ai_pathfinder.c
+++ b/ai_pathfinder.c
@@ -153,12 +153,12 @@ static int32 AyStar_AiPathFinder_CalculateH(AyStar *aystar, AyStarNode *current,
 	int r, r2;
 	if (PathFinderInfo->end_direction != AI_PATHFINDER_NO_DIRECTION) {
 		// The station is pointing to a direction, add a tile towards that direction, so the H-value is more accurate
-		r = GetTileDist(current->tile, PathFinderInfo->end_tile_tl + TileOffsByDir(PathFinderInfo->end_direction));
-		r2 = GetTileDist(current->tile, PathFinderInfo->end_tile_br + TileOffsByDir(PathFinderInfo->end_direction));
+		r = DistanceManhattan(current->tile, PathFinderInfo->end_tile_tl + TileOffsByDir(PathFinderInfo->end_direction));
+		r2 = DistanceManhattan(current->tile, PathFinderInfo->end_tile_br + TileOffsByDir(PathFinderInfo->end_direction));
 	} else {
 		// No direction, so just get the fastest route to the station
-		r = GetTileDist(current->tile, PathFinderInfo->end_tile_tl);
-		r2 = GetTileDist(current->tile, PathFinderInfo->end_tile_br);
+		r = DistanceManhattan(current->tile, PathFinderInfo->end_tile_tl);
+		r2 = DistanceManhattan(current->tile, PathFinderInfo->end_tile_br);
 	}
 	// See if the bottomright is faster than the topleft..
 	if (r2 < r) r = r2;
diff --git a/aircraft_cmd.c b/aircraft_cmd.c
index 48fbfbbbd..3b9b97358 100644
--- a/aircraft_cmd.c
+++ b/aircraft_cmd.c
@@ -48,7 +48,7 @@ static uint32 FindNearestHangar(Vehicle *v)
 				// don't crash the planes if we know they can't land at the airport
 				if (HASBIT(v->subtype,1) && st->airport_type == AT_SMALL && !_cheats.no_jetcrash.value) continue;
 
-				temp_distance = GetTileDistAdv(v->tile, st->airport_tile);
+				temp_distance = DistanceSquare(v->tile, st->airport_tile);
 				if (temp_distance < distance) {
 					distance = temp_distance;
 					index_to_target = st->index;
diff --git a/economy.c b/economy.c
index b8c6ebb39..cc92b64db 100644
--- a/economy.c
+++ b/economy.c
@@ -896,7 +896,7 @@ static void FindSubsidyPassengerRoute(FoundRoute *fr)
 	if (from==to || to->xy == 0 || to->population < 400 || to->pct_pass_transported > 42)
 		return;
 
-	fr->distance = GetTileDist(from->xy, to->xy);
+	fr->distance = DistanceManhattan(from->xy, to->xy);
 }
 
 static void FindSubsidyCargoRoute(FoundRoute *fr)
@@ -937,7 +937,7 @@ static void FindSubsidyCargoRoute(FoundRoute *fr)
 		// Only want big towns
 		if (t->xy == 0 || t->population < 900)
 			return;
-		fr->distance = GetTileDist(i->xy, t->xy);
+		fr->distance = DistanceManhattan(i->xy, t->xy);
 		fr->to = t;
 	} else {
 		// The destination is an industry
@@ -949,7 +949,7 @@ static void FindSubsidyCargoRoute(FoundRoute *fr)
 				cargo != i2->accepts_cargo[1] &&
 				cargo != i2->accepts_cargo[2]))
 			return;
-		fr->distance = GetTileDist(i->xy, i2->xy);
+		fr->distance = DistanceManhattan(i->xy, i2->xy);
 		fr->to = i2;
 	}
 }
@@ -1132,7 +1132,7 @@ static void DeliverGoodsToIndustry(TileIndex xy, byte cargo_type, int num_pieces
 				 == ind->accepts_cargo[1] || cargo_type == ind->accepts_cargo[2]) &&
 				 ind->produced_cargo[0] != 0xFF &&
 				 ind->produced_cargo[0] != cargo_type &&
-				 (t=GetTileDist(ind->xy, xy)) < u) {
+				 (t = DistanceManhattan(ind->xy, xy)) < u) {
 			u = t;
 			best = ind;
 		}
@@ -1171,7 +1171,7 @@ static bool CheckSubsidised(Station *from, Station *to, byte cargo_type)
 			} else {
 				xy = (GetIndustry(s->from))->xy;
 			}
-			if (GetTileDist1D(xy, from->xy) > 9)
+			if (DistanceMax(xy, from->xy) > 9)
 				continue;
 
 			/* Check distance from dest */
@@ -1181,7 +1181,7 @@ static bool CheckSubsidised(Station *from, Station *to, byte cargo_type)
 				xy = (GetIndustry(s->to))->xy;
 			}
 
-			if (GetTileDist1D(xy, to->xy) > 9)
+			if (DistanceMax(xy, to->xy) > 9)
 				continue;
 
 			/* Found a subsidy, change the values to indicate that it's in use */
@@ -1242,7 +1242,7 @@ static int32 DeliverGoods(int num_pieces, byte cargo_type, byte source, byte des
 
 	// Determine profit
 	{
-		int t = GetTileDist(s_from->xy, s_to->xy);
+		int t = DistanceManhattan(s_from->xy, s_to->xy);
 		int r = num_pieces;
 		profit = 0;
 		do {
diff --git a/functions.h b/functions.h
index 36482e9a1..fdcf33ba5 100644
--- a/functions.h
+++ b/functions.h
@@ -169,12 +169,6 @@ void NetworkSend_Command(uint32 tile, uint32 p1, uint32 p2, uint32 cmd, CommandC
 /* misc_cmd.c */
 void PlaceTreesRandomly(void);
 
-uint GetTileDist(TileIndex xy1, TileIndex xy2);
-uint GetTileDist1D(TileIndex xy1, TileIndex xy2);
-uint GetTileDist1Db(TileIndex xy1, TileIndex xy2);
-uint GetTileDistAdv(TileIndex xy1, TileIndex xy2);
-bool CheckDistanceFromEdge(TileIndex tile, uint distance);
-
 void InitializeLandscapeVariables(bool only_constants);
 
 /* misc.c */
diff --git a/industry_cmd.c b/industry_cmd.c
index 149d7fc68..126b596c7 100644
--- a/industry_cmd.c
+++ b/industry_cmd.c
@@ -1346,7 +1346,7 @@ static bool CheckIfIndustryTilesAreFree(uint tile, const IndustryTileTable *it,
 						return false;
 					}
 				} else if (type == IT_TOY_SHOP) {
-					if (GetTileDist1D(t->xy, cur_tile) > 9)
+					if (DistanceMax(t->xy, cur_tile) > 9)
 						return false;
 					if (ti.type != MP_HOUSE) goto do_clear;
 				} else if (type == IT_WATER_TOWER) {
@@ -1379,7 +1379,7 @@ static bool CheckIfTooCloseToIndustry(uint tile, int type)
 	FOR_ALL_INDUSTRIES(i) {
 		// check if an industry that accepts the same goods is nearby
 		if (i->xy != 0 &&
-				(GetTileDist1D(tile, i->xy) <= 14) &&
+				(DistanceMax(tile, i->xy) <= 14) &&
 				spec->accepts_cargo[0] != 0xFF &&
 				spec->accepts_cargo[0] == i->accepts_cargo[0] &&
 				!(_game_mode == GM_EDITOR &&
@@ -1392,7 +1392,7 @@ static bool CheckIfTooCloseToIndustry(uint tile, int type)
 		// check "not close to" field.
 		if (i->xy != 0 &&
 				(i->type == spec->a || i->type == spec->b || i->type == spec->c) &&
-				GetTileDist1D(tile, i->xy) <= 14) {
+				DistanceMax(tile, i->xy) <= 14) {
 			_error_message = STR_INDUSTRY_TOO_CLOSE;
 			return false;
 		}
diff --git a/map.c b/map.c
index 37f1e22dc..2481843d2 100644
--- a/map.c
+++ b/map.c
@@ -108,6 +108,50 @@ uint ScaleByMapSize1D(uint n)
 }
 
 
+uint DistanceManhattan(TileIndex t0, TileIndex t1)
+{
+	return
+		abs(TileX(t0) - TileX(t1)) +
+		abs(TileY(t0) - TileY(t1));
+}
+
+
+uint DistanceSquare(TileIndex t0, TileIndex t1)
+{
+	const int x = TileX(t0) - TileX(t1);
+	const int y = TileY(t0) - TileY(t1);
+	return x * x + y * y;
+}
+
+
+uint DistanceMax(TileIndex t0, TileIndex t1)
+{
+	const uint x = abs(TileX(t0) - TileX(t1));
+	const uint y = abs(TileY(t0) - TileY(t1));
+	return x > y ? x : y;
+}
+
+
+uint DistanceMaxPlusManhattan(TileIndex t0, TileIndex t1)
+{
+	const uint x = abs(TileX(t0) - TileX(t1));
+	const uint y = abs(TileY(t0) - TileY(t1));
+	return x > y ? 2 * x + y : 2 * y + x;
+}
+
+
+uint DistanceFromEdge(TileIndex tile)
+{
+	const uint xl = TileX(tile);
+	const uint yl = TileY(tile);
+	const uint xh = MapSizeX() - 1 - xl;
+	const uint yh = MapSizeY() - 1 - yl;
+	const uint minl = xl < yl ? xl : yl;
+	const uint minh = xh < yh ? xh : yh;
+	return minl < minh ? minl : minh;
+}
+
+
 const TileIndexDiffC _tileoffs_by_dir[] = {
 	{-1,  0},
 	{ 0,  1},
diff --git a/map.h b/map.h
index d5628fe45..605b89495 100644
--- a/map.h
+++ b/map.h
@@ -72,6 +72,14 @@ static inline TileIndexDiff ToTileIndexDiff(TileIndexDiffC tidc)
 #define TILE_ADDXY(tile, x, y) TILE_ADD(tile, TILE_XY(x, y))
 
 
+// Functions to calculate distances
+uint DistanceManhattan(TileIndex, TileIndex); // also known as L1-Norm
+uint DistanceSquare(TileIndex, TileIndex); // euclidian- or L2-Norm squared
+uint DistanceMax(TileIndex, TileIndex); // also known as L-Infinity-Norm
+uint DistanceMaxPlusManhattan(TileIndex, TileIndex); // Max + Manhattan
+uint DistanceFromEdge(TileIndex); // shortest distance from any edge of the map
+
+
 static inline TileIndexDiff TileOffsByDir(uint dir)
 {
 	extern const TileIndexDiffC _tileoffs_by_dir[4];
diff --git a/misc.c b/misc.c
index d8bd83b3f..f4e363585 100644
--- a/misc.c
+++ b/misc.c
@@ -533,43 +533,6 @@ void InitializeLandscapeVariables(bool only_constants)
 	}
 }
 
-// distance in Manhattan metric
-uint GetTileDist(TileIndex xy1, TileIndex xy2)
-{
-	return myabs(TileX(xy1) - TileX(xy2)) +
-				myabs(TileY(xy1) - TileY(xy2));
-}
-
-// maximum distance in x _or_ y
-uint GetTileDist1D(TileIndex xy1, TileIndex xy2)
-{
-	return max(myabs(TileX(xy1) - TileX(xy2)),
-						 myabs(TileY(xy1) - TileY(xy2)));
-}
-
-uint GetTileDist1Db(TileIndex xy1, TileIndex xy2)
-{
-	int a = myabs(TileX(xy1) - TileX(xy2));
-	int b = myabs(TileY(xy1) - TileY(xy2));
-
-	if (a > b)
-		return a*2+b;
-	else
-		return b*2+a;
-}
-
-uint GetTileDistAdv(TileIndex xy1, TileIndex xy2)
-{
-	uint a = myabs(TileX(xy1) - TileX(xy2));
-	uint b = myabs(TileY(xy1) - TileY(xy2));
-	return a*a+b*b;
-}
-
-bool CheckDistanceFromEdge(TileIndex tile, uint distance)
-{
-	return IS_INT_INSIDE(TileX(tile), distance, MapSizeX() - distance) &&
-			IS_INT_INSIDE(TileY(tile), distance, MapSizeY() - distance);
-}
 
 void OnNewDay_Train(Vehicle *v);
 void OnNewDay_RoadVeh(Vehicle *v);
diff --git a/order_cmd.c b/order_cmd.c
index 480e058ae..809bed18b 100644
--- a/order_cmd.c
+++ b/order_cmd.c
@@ -140,7 +140,7 @@ int32 CmdInsertOrder(int x, int y, uint32 flags, uint32 veh_sel, uint32 packed_o
 	if (v->type == VEH_Ship && IS_HUMAN_PLAYER(v->owner) &&
 		sel != 0 && GetVehicleOrder(v, sel - 1)->type == OT_GOTO_STATION) {
 
-		int dist = GetTileDist(
+		int dist = DistanceManhattan(
 			GetStation(GetVehicleOrder(v, sel - 1)->station)->xy,
 			GetStation(new_order.station)->xy
 		);
diff --git a/rail_cmd.c b/rail_cmd.c
index f23d11b55..409884497 100644
--- a/rail_cmd.c
+++ b/rail_cmd.c
@@ -701,7 +701,7 @@ static Waypoint *FindDeletedWaypointCloseTo(uint tile)
 
 	for(cp = _waypoints; cp != endof(_waypoints); cp++) {
 		if (cp->deleted && cp->xy) {
-			cur_dist = GetTileDist(tile, cp->xy);
+			cur_dist = DistanceManhattan(tile, cp->xy);
 			if (cur_dist < thres) {
 				thres = cur_dist;
 				best = cp;
diff --git a/road_cmd.c b/road_cmd.c
index 7dd27b902..cb5133b51 100644
--- a/road_cmd.c
+++ b/road_cmd.c
@@ -973,7 +973,7 @@ static void TileLoop_Road(uint tile)
 
 			// Show an animation to indicate road work
 			if (t->road_build_months != 0 &&
-					!(GetTileDist(t->xy, tile) >= 8 && grp==0) &&
+					!(DistanceManhattan(t->xy, tile) >= 8 && grp == 0) &&
 					(_map5[tile]==5 || _map5[tile]==10)) {
 				if (GetTileSlope(tile, NULL) == 0 && EnsureNoVehicle(tile) && CHANCE16(1,20)) {
 					_map2[tile] = ((_map2[tile]&7) <= 1) ? 6 : 7;
diff --git a/roadveh_cmd.c b/roadveh_cmd.c
index d69894530..2297f6ab2 100644
--- a/roadveh_cmd.c
+++ b/roadveh_cmd.c
@@ -651,7 +651,7 @@ static void ProcessRoadVehOrder(Vehicle *v)
 			dist = malloc(num * sizeof(int32));
 
 			do {
-				*dist = GetTileDistAdv(v->tile, rs->xy);
+				*dist = DistanceSquare(v->tile, rs->xy);
 				if (*dist < mindist) {
 					v->dest_tile = rs->xy;
 				}
@@ -999,7 +999,7 @@ typedef struct {
 
 static bool EnumRoadTrackFindDist(uint tile, FindRoadToChooseData *frd, int track, uint length, byte *state)
 {
-	uint dist = GetTileDist(tile, frd->dest);
+	uint dist = DistanceManhattan(tile, frd->dest);
 	if (dist <= frd->mindist) {
 		if (dist != frd->mindist || length < frd->maxtracklen) {
 			frd->maxtracklen = length;
@@ -1577,9 +1577,9 @@ static void CheckIfRoadVehNeedsService(Vehicle *v)
 
 	i = FindClosestRoadDepot(v);
 
-	if (i < 0 || GetTileDist(v->tile, (&_depots[i])->xy) > 12) {
+	if (i < 0 || DistanceManhattan(v->tile, (&_depots[i])->xy) > 12) {
 		if (v->current_order.type == OT_GOTO_DEPOT && !(
-			GetTileDist(v->tile, v->dest_tile) > 25 && v->set_for_replacement)) {
+			DistanceManhattan(v->tile, v->dest_tile) > 25 && v->set_for_replacement)) {
 			/*  a vehicle needs a greater distance to a depot to loose it than to find it since
 			they can circle forever othervise if they are in a loop with an unlucky distance	*/
 			v->current_order.type = OT_DUMMY;
diff --git a/ship_cmd.c b/ship_cmd.c
index dec18586f..238a0b43e 100644
--- a/ship_cmd.c
+++ b/ship_cmd.c
@@ -73,7 +73,7 @@ static int FindClosestShipDepot(Vehicle *v)
 	for(i=0; i!=lengthof(_depots); i++) {
 		tile = _depots[i].xy;
 		if (IsTileType(tile, MP_WATER) && _map_owner[tile] == owner) {
-			dist = GetTileDist(tile, tile2);
+			dist = DistanceManhattan(tile, tile2);
 			if (dist < best_dist) {
 				best_dist = dist;
 				best_depot = i;
@@ -106,7 +106,7 @@ static void CheckIfShipNeedsService(Vehicle *v)
 
 	i = FindClosestShipDepot(v);
 
-	if (i < 0 || GetTileDist(v->tile, (&_depots[i])->xy) > 12) {
+	if (i < 0 || DistanceManhattan(v->tile, (&_depots[i])->xy) > 12) {
 		if (v->current_order.type == OT_GOTO_DEPOT) {
 			v->current_order.type = OT_DUMMY;
 			v->current_order.flags = 0;
@@ -499,7 +499,7 @@ static bool ShipTrackFollower(uint tile, PathFindShip *pfs, int track, uint leng
 
 	// Skip this tile in the calculation
 	if (tile != pfs->skiptile) {
-		pfs->best_bird_dist = minu(pfs->best_bird_dist, GetTileDist1Db(pfs->dest_coords, tile));
+		pfs->best_bird_dist = minu(pfs->best_bird_dist, DistanceMaxPlusManhattan(pfs->dest_coords, tile));
 	}
 
 	return false;
diff --git a/station_cmd.c b/station_cmd.c
index d6d81c702..c5a1475cc 100644
--- a/station_cmd.c
+++ b/station_cmd.c
@@ -318,7 +318,7 @@ static bool GenerateStationName(Station *st, uint tile, int flag)
 	}
 
 	/* check close enough to town to get central as name? */
-	if (GetTileDist1D(tile,t->xy) < 8) {
+	if (DistanceMax(tile,t->xy) < 8) {
 		found = M(STR_SV_STNAME);
 		if (HASBIT(free_names, M(STR_SV_STNAME))) goto done;
 
@@ -328,7 +328,7 @@ static bool GenerateStationName(Station *st, uint tile, int flag)
 
 	/* Check lakeside */
 	if (HASBIT(free_names, M(STR_SV_STNAME_LAKESIDE)) &&
-			!CheckDistanceFromEdge(tile, 20) &&
+			DistanceFromEdge(tile) < 20 &&
 			CountMapSquareAround(tile, MP_WATER, 0, 0) >= 5) {
 				found = M(STR_SV_STNAME_LAKESIDE);
 				goto done;
@@ -386,7 +386,7 @@ static Station *GetClosestStationFromTile(uint tile, uint threshold, byte owner)
 	uint cur_dist;
 
 	FOR_ALL_STATIONS(st) {
-		cur_dist = GetTileDist(tile, st->xy);
+		cur_dist = DistanceManhattan(tile, st->xy);
 		if (cur_dist < threshold && (owner == 0xFF || st->owner == owner) && (st->xy != 0)) {
 			threshold = cur_dist;
 			best_station = st;
@@ -2591,7 +2591,8 @@ void ModifyStationRatingAround(TileIndex tile, byte owner, int amount, uint radi
 	int i;
 
 	FOR_ALL_STATIONS(st) {
-		if (st->xy != 0 && st->owner == owner && GetTileDist(tile, st->xy) <= radius) {
+		if (st->xy != 0 && st->owner == owner &&
+				DistanceManhattan(tile, st->xy) <= radius) {
 			ge = st->goods;
 			for(i=0; i!=NUM_CARGO; i++,ge++) {
 				if (ge->enroute_from != 0xFF) {
diff --git a/town_cmd.c b/town_cmd.c
index 3f0a30c03..5a6839d2a 100644
--- a/town_cmd.c
+++ b/town_cmd.c
@@ -166,7 +166,7 @@ static bool IsCloseToTown(uint tile, uint dist)
 	Town *t;
 
 	FOR_ALL_TOWNS(t) {
-		if (t->xy != 0 && GetTileDist(tile, t->xy) < dist)
+		if (t->xy != 0 && DistanceManhattan(tile, t->xy) < dist)
 			return true;
 	}
 	return false;
@@ -970,7 +970,7 @@ int32 CmdBuildTown(int x, int y, uint32 flags, uint32 p1, uint32 p2)
 	SET_EXPENSES_TYPE(EXPENSES_OTHER);
 
 	// Check if too close to the edge of map
-	if (!CheckDistanceFromEdge(tile, 12))
+	if (DistanceFromEdge(tile) < 12)
 		return_cmd_error(STR_0237_TOO_CLOSE_TO_EDGE_OF_MAP);
 
 	// Can only build on clear flat areas.
@@ -1008,7 +1008,7 @@ Town *CreateRandomTown(void)
 	do {
 		// Generate a tile index not too close from the edge
 		tile = TILE_MASK(Random());
-		if (!CheckDistanceFromEdge(tile, 20))
+		if (DistanceFromEdge(tile) < 20)
 			continue;
 
 		// Make sure the tile is plain
@@ -1074,7 +1074,7 @@ int GetTownRadiusGroup(Town *t, uint tile)
 	uint dist;
 	int i,smallest;
 
-	dist = GetTileDistAdv(tile, t->xy);
+	dist = DistanceSquare(tile, t->xy);
 	if (t->fund_buildings_months && dist <= 25)
 		return 4;
 
@@ -1637,7 +1637,7 @@ static void UpdateTownGrowRate(Town *t)
 
 	n = 0;
 	FOR_ALL_STATIONS(st) {
-		if (GetTileDistAdv(st->xy, t->xy) <= t->radius[0]) {
+		if (DistanceSquare(st->xy, t->xy) <= t->radius[0]) {
 			if (st->time_since_load <= 20 || st->time_since_unload <= 20) {
 				n++;
 				if (st->owner < MAX_PLAYERS && t->ratings[st->owner] <= 1000-12)
@@ -1740,7 +1740,7 @@ Town *ClosestTownFromTile(uint tile, uint threshold)
 
 	FOR_ALL_TOWNS(t) {
 		if (t->xy != 0) {
-			dist = GetTileDist(tile, t->xy);
+			dist = DistanceManhattan(tile, t->xy);
 			if (dist < best) {
 				best = dist;
 				best_town = t;
diff --git a/train_cmd.c b/train_cmd.c
index 9c176c8df..2cbadb142 100644
--- a/train_cmd.c
+++ b/train_cmd.c
@@ -1598,7 +1598,7 @@ static bool TrainTrackFollower(uint tile, TrainTrackFollowerData *ttfd, int trac
 			return length >= ttfd->best_track_dist;
 
 		// didn't find station
-		dist = GetTileDist(tile, ttfd->dest_coords);
+		dist = DistanceManhattan(tile, ttfd->dest_coords);
 		if (dist < ttfd->best_bird_dist) {
 			ttfd->best_bird_dist = dist;
 			ttfd->best_track = state[1];