Feature: Multi-tile docks and docking points.

27 files changed, 471 insertions, 80 deletions

diff --git a/docs/landscape.html b/docs/landscape.html
index 1a6cd8386..4ee0da47e 100644
--- a/docs/landscape.html
+++ b/docs/landscape.html
@@ -249,6 +249,7 @@
    <td valign=top nowrap>&nbsp;</td>
    <td>
     <ul>
+     <li>m1 bit 7: Ship docking tile status (for half-tile with water)</li>
      <li>m1 bits 4..0: <a href="#OwnershipInfo">owner</a> of the tile</li>
      <li>m2: see signals</li>
      <li>m3 bits 7..4: see signals</li>
@@ -871,6 +872,7 @@
    <td valign=top nowrap>&nbsp;</td>
    <td>
     <ul>
+     <li>m1 bit 7: Ship docking tile status (for buoys)</li>
      <li>m1 bits 6..5: water class for buoys, water part of docks and for airport tiles</li>
      <li>m1 bits 4..0: <a href="#OwnershipInfo">owner</a> of the station</li>
      <li>m2: index into the array of stations</li>
@@ -1008,6 +1010,7 @@
    <td valign=top nowrap>&nbsp;</td>
    <td>
     <ul>
+     <li>m1 bit 7: Ship docking tile status</li>
      <li>m1 bits 6..5 : Water class (sea, canal or river)
      <li>m1 bits 4..0: <a href="#OwnershipInfo">owner</a> (for sea, rivers, and coasts normally <tt>11</tt>)</li>
      <li>m2: Depot index (for depots only)</li>
@@ -1459,6 +1462,7 @@
    <td valign=top nowrap>&nbsp;</td>
    <td>
     <ul>
+     <li>m1 bit 7: Ship docking tile status (for aqueducts)</li>
      <li>m1 bits 4..0: <a href="#OwnershipInfo">owner</a></li>
      <li>m3 bits 7..4: <a href="#OwnershipInfo">owner</a> of tram</li>
      <li>m4: <a href="#RoadType">Roadtype</a></li>
diff --git a/docs/landscape_grid.html b/docs/landscape_grid.html
index 5d65214cb..d4a88d0bb 100644
--- a/docs/landscape_grid.html
+++ b/docs/landscape_grid.html
@@ -100,7 +100,7 @@ the array so you can quickly see what is used and what is not.
       <td class="caption">rail</td>
       <td class="bits">XXXX XXXX</td>
       <td class="bits">XXXX XXXX</td>
-      <td class="bits"><span class="free">OOO</span>X XXXX</td>
+      <td class="bits">X<span class="free">OO</span>X XXXX</td>
       <td class="bits"><span class="free">OOOO</span> XXXX <span class="free">OOOO OOOO</span></td>
       <td class="bits"><span class="free">OOOO OOOO</span></td>
       <td class="bits"><span class="free">OOOO</span> XXXX</td>
@@ -208,7 +208,7 @@ the array so you can quickly see what is used and what is not.
       <td class="caption">rail station</td>
       <td class="bits">XXXX XXXX</td>
       <td class="bits">XXXX XXXX</td>
-      <td class="bits"><span class="free">O</span>XXX XXXX</td>
+      <td class="bits">XXXX XXXX</td>
       <td class="bits">XXXX XXXX XXXX XXXX</td>
       <td class="bits">XXXX <span class="free">OOOO</span></td>
       <td class="bits">XXXX XXXX</td>
@@ -300,7 +300,7 @@ the array so you can quickly see what is used and what is not.
       <td class="caption">sea, shore</td>
       <td class="bits">XXXX XXXX</td>
       <td class="bits">XXXX XXXX</td>
-      <td class="bits"><span class="free">O</span>XXX XXXX</td>
+      <td class="bits">XXXX XXXX</td>
       <td class="bits"><span class="free">OOOO OOOO OOOO OOOO</span></td>
       <td class="bits"><span class="free">OOOO OOOO</span></td>
       <td class="bits"><span class="free">OOOO OOOO</span></td>
@@ -354,7 +354,7 @@ the array so you can quickly see what is used and what is not.
       <td class="caption">tunnel entrance</td>
       <td class="bits">XXXX XXXX</td>
       <td class="bits">XXXX XXXX</td>
-      <td class="bits"><span class="free">OOO</span>X XXXX</td>
+      <td class="bits">X<span class="free">OO</span>X XXXX</td>
       <td class="bits"><span class="free">OOOO OOOO OOOO OOOO</span></td>
       <td class="bits">XXXX <span class="free">OOOO</span></td>
       <td class="bits"><span class="free">OO</span>XX XXXX</td>
diff --git a/src/bridge_map.h b/src/bridge_map.h
index 1461df13a..be37dfd71 100644
--- a/src/bridge_map.h
+++ b/src/bridge_map.h
@@ -15,6 +15,7 @@
 #include "rail_map.h"
 #include "road_map.h"
 #include "bridge.h"
+#include "water_map.h"
 
 /**
  * Checks if this is a bridge, instead of a tunnel
@@ -130,6 +131,7 @@ static inline void MakeBridgeRamp(TileIndex t, Owner o, BridgeType bridgetype, D
 {
 	SetTileType(t, MP_TUNNELBRIDGE);
 	SetTileOwner(t, o);
+	SetDockingTile(t, false);
 	_m[t].m2 = 0;
 	_m[t].m3 = 0;
 	_m[t].m4 = INVALID_ROADTYPE;
diff --git a/src/industry_cmd.cpp b/src/industry_cmd.cpp
index 06c6cde56..4e4ff5c82 100644
--- a/src/industry_cmd.cpp
+++ b/src/industry_cmd.cpp
@@ -155,6 +155,13 @@ Industry::~Industry()
 		}
 	}
 
+	if (this->neutral_station != nullptr) {
+		/* Remove possible docking tiles */
+		TILE_AREA_LOOP(tile_cur, this->location) {
+			ClearDockingTilesCheckingNeighbours(tile_cur);
+		}
+	}
+
 	if (GetIndustrySpec(this->type)->behaviour & INDUSTRYBEH_PLANT_FIELDS) {
 		TileArea ta = TileArea(this->location.tile, 0, 0).Expand(21);
 
diff --git a/src/order_cmd.cpp b/src/order_cmd.cpp
index 26b999af7..ed2f444cc 100644
--- a/src/order_cmd.cpp
+++ b/src/order_cmd.cpp
@@ -2198,7 +2198,7 @@ bool ProcessOrders(Vehicle *v)
 
 	/* If it is unchanged, keep it. */
 	if (order->Equals(v->current_order) && (v->type == VEH_AIRCRAFT || v->dest_tile != 0) &&
-			(v->type != VEH_SHIP || !order->IsType(OT_GOTO_STATION) || Station::Get(order->GetDestination())->dock_tile != INVALID_TILE)) {
+			(v->type != VEH_SHIP || !order->IsType(OT_GOTO_STATION) || Station::Get(order->GetDestination())->ship_station.tile != INVALID_TILE > 0)) {
 		return false;
 	}
 
diff --git a/src/pathfinder/npf/npf.cpp b/src/pathfinder/npf/npf.cpp
index 2cf333890..53f84f2a7 100644
--- a/src/pathfinder/npf/npf.cpp
+++ b/src/pathfinder/npf/npf.cpp
@@ -165,8 +165,8 @@ static int32 NPFCalcStationOrTileHeuristic(AyStar *as, AyStarNode *current, Open
 	uint dist;
 	AyStarUserData *user = (AyStarUserData *)as->user_data;
 
-	/* for train-stations, we are going to aim for the closest station tile */
-	if (user->type != TRANSPORT_WATER && fstd->station_index != INVALID_STATION) {
+	/* aim for the closest station tile */
+	if (fstd->station_index != INVALID_STATION) {
 		to = CalcClosestStationTile(fstd->station_index, from, fstd->station_type);
 	}
 
@@ -563,6 +563,12 @@ static int32 NPFFindStationOrTile(const AyStar *as, const OpenListNode *current)
 
 	if (fstd->station_index == INVALID_STATION && tile == fstd->dest_coords) return AYSTAR_FOUND_END_NODE;
 
+	if (fstd->v->type == VEH_SHIP) {
+		/* Ships do not actually reach the destination station, so we check for a docking tile instead. */
+		if (IsDockingTile(tile) && IsShipDestinationTile(tile, fstd->station_index)) return AYSTAR_FOUND_END_NODE;
+		return AYSTAR_DONE;
+	}
+
 	if (IsTileType(tile, MP_STATION) && GetStationIndex(tile) == fstd->station_index) {
 		if (fstd->v->type == VEH_TRAIN) return AYSTAR_FOUND_END_NODE;
 
@@ -1111,10 +1117,16 @@ static void NPFFillWithOrderData(NPFFindStationOrTileData *fstd, const Vehicle *
 	 * dest_tile, not just any stop of that station.
 	 * So only for train orders to stations we fill fstd->station_index, for all
 	 * others only dest_coords */
-	if (v->type != VEH_SHIP && (v->current_order.IsType(OT_GOTO_STATION) || v->current_order.IsType(OT_GOTO_WAYPOINT))) {
-		assert(v->IsGroundVehicle());
+	if (v->current_order.IsType(OT_GOTO_STATION) || v->current_order.IsType(OT_GOTO_WAYPOINT)) {
 		fstd->station_index = v->current_order.GetDestination();
-		fstd->station_type = (v->type == VEH_TRAIN) ? (v->current_order.IsType(OT_GOTO_STATION) ? STATION_RAIL : STATION_WAYPOINT) : (RoadVehicle::From(v)->IsBus() ? STATION_BUS : STATION_TRUCK);
+		if (v->type == VEH_TRAIN) {
+			fstd->station_type = v->current_order.IsType(OT_GOTO_STATION) ? STATION_RAIL : STATION_WAYPOINT;
+		} else if (v->type == VEH_ROAD) {
+			fstd->station_type = RoadVehicle::From(v)->IsBus() ? STATION_BUS : STATION_TRUCK;
+		} else if (v->type == VEH_SHIP) {
+			fstd->station_type = v->current_order.IsType(OT_GOTO_STATION) ? STATION_DOCK : STATION_BUOY;
+		}
+
 		fstd->not_articulated = v->type == VEH_ROAD && !RoadVehicle::From(v)->HasArticulatedPart();
 		/* Let's take the closest tile of the station as our target for vehicles */
 		fstd->dest_coords = CalcClosestStationTile(fstd->station_index, v->tile, fstd->station_type);
diff --git a/src/pathfinder/yapf/yapf_node_ship.hpp b/src/pathfinder/yapf/yapf_node_ship.hpp
index df4254fd9..a8f827071 100644
--- a/src/pathfinder/yapf/yapf_node_ship.hpp
+++ b/src/pathfinder/yapf/yapf_node_ship.hpp
@@ -14,7 +14,19 @@
 
 /** Yapf Node for ships */
 template <class Tkey_>
-struct CYapfShipNodeT : CYapfNodeT<Tkey_, CYapfShipNodeT<Tkey_> > { };
+struct CYapfShipNodeT : CYapfNodeT<Tkey_, CYapfShipNodeT<Tkey_> > {
+	typedef CYapfNodeT<Tkey_, CYapfShipNodeT<Tkey_> > base;
+
+	TileIndex m_segment_last_tile;
+	Trackdir  m_segment_last_td;
+
+	void Set(CYapfShipNodeT *parent, TileIndex tile, Trackdir td, bool is_choice)
+	{
+		base::Set(parent, tile, td, is_choice);
+		m_segment_last_tile = tile;
+		m_segment_last_td   = td;
+	}
+};
 
 /* now define two major node types (that differ by key type) */
 typedef CYapfShipNodeT<CYapfNodeKeyExitDir>  CYapfShipNodeExitDir;
diff --git a/src/pathfinder/yapf/yapf_ship.cpp b/src/pathfinder/yapf/yapf_ship.cpp
index 09a4fc76a..c665fc53e 100644
--- a/src/pathfinder/yapf/yapf_ship.cpp
+++ b/src/pathfinder/yapf/yapf_ship.cpp
@@ -11,12 +11,95 @@
 
 #include "../../stdafx.h"
 #include "../../ship.h"
+#include "../../industry.h"
 
 #include "yapf.hpp"
 #include "yapf_node_ship.hpp"
 
 #include "../../safeguards.h"
 
+template <class Types>
+class CYapfDestinationTileWaterT
+{
+public:
+	typedef typename Types::Tpf Tpf;                     ///< the pathfinder class (derived from THIS class)
+	typedef typename Types::TrackFollower TrackFollower;
+	typedef typename Types::NodeList::Titem Node;        ///< this will be our node type
+	typedef typename Node::Key Key;                      ///< key to hash tables
+
+protected:
+	TileIndex    m_destTile;
+	TrackdirBits m_destTrackdirs;
+	StationID    m_destStation;
+
+public:
+	void SetDestination(const Ship *v)
+	{
+		if (v->current_order.IsType(OT_GOTO_STATION)) {
+			m_destStation   = v->current_order.GetDestination();
+			m_destTile      = CalcClosestStationTile(m_destStation, v->tile, STATION_DOCK);
+			m_destTrackdirs = INVALID_TRACKDIR_BIT;
+		} else {
+			m_destStation   = INVALID_STATION;
+			m_destTile      = v->dest_tile;
+			m_destTrackdirs = TrackStatusToTrackdirBits(GetTileTrackStatus(v->dest_tile, TRANSPORT_WATER, 0));
+		}
+	}
+
+protected:
+	/** to access inherited path finder */
+	inline Tpf& Yapf()
+	{
+		return *static_cast<Tpf*>(this);
+	}
+
+public:
+	/** Called by YAPF to detect if node ends in the desired destination */
+	inline bool PfDetectDestination(Node& n)
+	{
+		return PfDetectDestinationTile(n.m_segment_last_tile, n.m_segment_last_td);
+	}
+
+	inline bool PfDetectDestinationTile(TileIndex tile, Trackdir trackdir)
+	{
+		if (m_destStation != INVALID_STATION) {
+			return IsDockingTile(tile) && IsShipDestinationTile(tile, m_destStation);
+		}
+
+		return tile == m_destTile && ((m_destTrackdirs & TrackdirToTrackdirBits(trackdir)) != TRACKDIR_BIT_NONE);
+	}
+
+	/**
+	 * Called by YAPF to calculate cost estimate. Calculates distance to the destination
+	 *  adds it to the actual cost from origin and stores the sum to the Node::m_estimate
+	 */
+	inline bool PfCalcEstimate(Node& n)
+	{
+		static const int dg_dir_to_x_offs[] = {-1, 0, 1, 0};
+		static const int dg_dir_to_y_offs[] = {0, 1, 0, -1};
+		if (PfDetectDestination(n)) {
+			n.m_estimate = n.m_cost;
+			return true;
+		}
+
+		TileIndex tile = n.m_segment_last_tile;
+		DiagDirection exitdir = TrackdirToExitdir(n.m_segment_last_td);
+		int x1 = 2 * TileX(tile) + dg_dir_to_x_offs[(int)exitdir];
+		int y1 = 2 * TileY(tile) + dg_dir_to_y_offs[(int)exitdir];
+		int x2 = 2 * TileX(m_destTile);
+		int y2 = 2 * TileY(m_destTile);
+		int dx = abs(x1 - x2);
+		int dy = abs(y1 - y2);
+		int dmin = min(dx, dy);
+		int dxy = abs(dx - dy);
+		int d = dmin * YAPF_TILE_CORNER_LENGTH + (dxy - 1) * (YAPF_TILE_LENGTH / 2);
+		n.m_estimate = n.m_cost + d;
+		assert(n.m_estimate >= n.m_parent->m_estimate);
+		return true;
+	}
+};
+
+
 /** Node Follower module of YAPF for ships */
 template <class Types>
 class CYapfFollowShipT
@@ -75,14 +158,12 @@ public:
 
 		/* convert origin trackdir to TrackdirBits */
 		TrackdirBits trackdirs = TrackdirToTrackdirBits(trackdir);
-		/* get available trackdirs on the destination tile */
-		TrackdirBits dest_trackdirs = TrackStatusToTrackdirBits(GetTileTrackStatus(v->dest_tile, TRANSPORT_WATER, 0));
 
 		/* create pathfinder instance */
 		Tpf pf;
 		/* set origin and destination nodes */
 		pf.SetOrigin(src_tile, trackdirs);
-		pf.SetDestination(v->dest_tile, dest_trackdirs);
+		pf.SetDestination(v);
 		/* find best path */
 		path_found = pf.FindPath(v);
 
@@ -124,14 +205,11 @@ public:
 	 */
 	static bool CheckShipReverse(const Ship *v, TileIndex tile, Trackdir td1, Trackdir td2)
 	{
-		/* get available trackdirs on the destination tile */
-		TrackdirBits dest_trackdirs = TrackStatusToTrackdirBits(GetTileTrackStatus(v->dest_tile, TRANSPORT_WATER, 0));
-
 		/* create pathfinder instance */
 		Tpf pf;
 		/* set origin and destination nodes */
 		pf.SetOrigin(tile, TrackdirToTrackdirBits(td1) | TrackdirToTrackdirBits(td2));
-		pf.SetDestination(v->dest_tile, dest_trackdirs);
+		pf.SetDestination(v);
 		/* find best path */
 		if (!pf.FindPath(v)) return false;
 
@@ -230,7 +308,7 @@ struct CYapfShip_TypesT
 	typedef CYapfBaseT<Types>                 PfBase;        // base pathfinder class
 	typedef CYapfFollowShipT<Types>           PfFollow;      // node follower
 	typedef CYapfOriginTileT<Types>           PfOrigin;      // origin provider
-	typedef CYapfDestinationTileT<Types>      PfDestination; // destination/distance provider
+	typedef CYapfDestinationTileWaterT<Types> PfDestination; // destination/distance provider
 	typedef CYapfSegmentCostCacheNoneT<Types> PfCache;       // segment cost cache provider
 	typedef CYapfCostShipT<Types>             PfCost;        // cost provider
 };
diff --git a/src/rail_cmd.cpp b/src/rail_cmd.cpp
index ab87fc40f..df862d4f2 100644
--- a/src/rail_cmd.cpp
+++ b/src/rail_cmd.cpp
@@ -570,6 +570,7 @@ CommandCost CmdBuildSingleRail(TileIndex tile, DoCommandFlag flags, uint32 p1, u
 		default: {
 			/* Will there be flat water on the lower halftile? */
 			bool water_ground = IsTileType(tile, MP_WATER) && IsSlopeWithOneCornerRaised(tileh);
+			bool docking = IsPossibleDockingTile(tile) && IsDockingTile(tile);
 
 			CommandCost ret = CheckRailSlope(tileh, trackbit, TRACK_BIT_NONE, tile);
 			if (ret.Failed()) return ret;
@@ -586,7 +587,10 @@ CommandCost CmdBuildSingleRail(TileIndex tile, DoCommandFlag flags, uint32 p1, u
 
 			if (flags & DC_EXEC) {
 				MakeRailNormal(tile, _current_company, trackbit, railtype);
-				if (water_ground) SetRailGroundType(tile, RAIL_GROUND_WATER);
+				if (water_ground) {
+					SetRailGroundType(tile, RAIL_GROUND_WATER);
+					SetDockingTile(tile, docking);
+				}
 				Company::Get(_current_company)->infrastructure.rail[railtype]++;
 				DirtyCompanyInfrastructureWindows(_current_company);
 			}
@@ -708,7 +712,9 @@ CommandCost CmdRemoveSingleRail(TileIndex tile, DoCommandFlag flags, uint32 p1,
 					Slope tileh = GetTileSlope(tile);
 					/* If there is flat water on the lower halftile, convert the tile to shore so the water remains */
 					if (GetRailGroundType(tile) == RAIL_GROUND_WATER && IsSlopeWithOneCornerRaised(tileh)) {
+						bool docking = IsDockingTile(tile);
 						MakeShore(tile);
+						SetDockingTile(tile, docking);
 					} else {
 						DoClearSquare(tile);
 					}
diff --git a/src/rail_map.h b/src/rail_map.h
index 74afe5ace..0142559e7 100644
--- a/src/rail_map.h
+++ b/src/rail_map.h
@@ -17,6 +17,7 @@
 #include "signal_func.h"
 #include "track_func.h"
 #include "tile_map.h"
+#include "water_map.h"
 #include "signal_type.h"
 
 
@@ -521,6 +522,7 @@ static inline void MakeRailNormal(TileIndex t, Owner o, TrackBits b, RailType r)
 {
 	SetTileType(t, MP_RAILWAY);
 	SetTileOwner(t, o);
+	SetDockingTile(t, false);
 	_m[t].m2 = 0;
 	_m[t].m3 = 0;
 	_m[t].m4 = 0;
@@ -535,6 +537,7 @@ static inline void MakeRailDepot(TileIndex t, Owner o, DepotID did, DiagDirectio
 {
 	SetTileType(t, MP_RAILWAY);
 	SetTileOwner(t, o);
+	SetDockingTile(t, false);
 	_m[t].m2 = did;
 	_m[t].m3 = 0;
 	_m[t].m4 = 0;
diff --git a/src/saveload/afterload.cpp b/src/saveload/afterload.cpp
index 662f5a77b..770237d53 100644
--- a/src/saveload/afterload.cpp
+++ b/src/saveload/afterload.cpp
@@ -57,6 +57,7 @@
 #include "../error.h"
 #include "../disaster_vehicle.h"
 #include "../ship.h"
+#include "../water.h"
 
 
 #include "saveload_internal.h"
@@ -675,7 +676,6 @@ bool AfterLoadGame()
 		Station *st;
 		FOR_ALL_STATIONS(st) {
 			if (st->airport.tile       == 0) st->airport.tile = INVALID_TILE;
-			if (st->dock_tile          == 0) st->dock_tile    = INVALID_TILE;
 			if (st->train_station.tile == 0) st->train_station.tile   = INVALID_TILE;
 		}
 
@@ -3177,6 +3177,27 @@ bool AfterLoadGame()
 		}
 	}
 
+	/* Update structures for multitile docks */
+	if (IsSavegameVersionBefore(SLV_MULTITILE_DOCKS)) {
+		for (TileIndex t = 0; t < map_size; t++) {
+			/* Clear docking tile flag from relevant tiles as it
+			 * was not previously cleared. */
+			if (IsTileType(t, MP_WATER) || IsTileType(t, MP_RAILWAY) || IsTileType(t, MP_STATION) || IsTileType(t, MP_TUNNELBRIDGE)) {
+				SetDockingTile(t, false);
+			}
+			/* Add docks and oilrigs to Station::ship_station. */
+			if (IsTileType(t, MP_STATION)) {
+				if (IsDock(t) || IsOilRig(t)) Station::GetByTile(t)->ship_station.Add(t);
+			}
+		}
+
+		/* Scan for docking tiles */
+		Station *st;
+		FOR_ALL_STATIONS(st) {
+			if (st->ship_station.tile != INVALID_TILE) UpdateStationDockingTiles(st);
+		}
+	}
+
 	/* Compute station catchment areas. This is needed here in case UpdateStationAcceptance is called below. */
 	Station::RecomputeCatchmentForAll();
 
diff --git a/src/saveload/oldloader_sl.cpp b/src/saveload/oldloader_sl.cpp
index f7309a474..2287d30a1 100644
--- a/src/saveload/oldloader_sl.cpp
+++ b/src/saveload/oldloader_sl.cpp
@@ -725,7 +725,7 @@ static const OldChunks station_chunk[] = {
 	OCL_NULL( 4 ), ///< bus/lorry tile
 	OCL_SVAR(   OC_TILE, Station, train_station.tile ),
 	OCL_SVAR(   OC_TILE, Station, airport.tile ),
-	OCL_SVAR(   OC_TILE, Station, dock_tile ),
+	OCL_NULL( 4 ), ///< dock tile
 	OCL_SVAR( OC_FILE_U8 | OC_VAR_U16, Station, train_station.w ),
 
 	OCL_NULL( 1 ),         ///< sort-index, no longer in use
diff --git a/src/saveload/saveload.h b/src/saveload/saveload.h
index fd8b3695f..323662f3f 100644
--- a/src/saveload/saveload.h
+++ b/src/saveload/saveload.h
@@ -301,6 +301,7 @@ enum SaveLoadVersion : uint16 {
 	SLV_ROAD_TYPES,                         ///< 214  PR#6811 NewGRF road types.
 
 	SLV_SCRIPT_MEMLIMIT,                    ///< 215  PR#7516 Limit on AI/GS memory consumption.
+	SLV_MULTITILE_DOCKS,                    ///< 216  PR#7380 Multiple docks per station.
 
 	SL_MAX_VERSION,                         ///< Highest possible saveload version
 };
diff --git a/src/saveload/station_sl.cpp b/src/saveload/station_sl.cpp
index 5e94de1a2..b9dcbd9e8 100644
--- a/src/saveload/station_sl.cpp
+++ b/src/saveload/station_sl.cpp
@@ -174,8 +174,8 @@ static const SaveLoad _old_station_desc[] = {
 	SLE_CONDVAR(Station, train_station.tile,         SLE_UINT32,                  SLV_6, SL_MAX_VERSION),
 	SLE_CONDVAR(Station, airport.tile,               SLE_FILE_U16 | SLE_VAR_U32,  SL_MIN_VERSION, SLV_6),
 	SLE_CONDVAR(Station, airport.tile,               SLE_UINT32,                  SLV_6, SL_MAX_VERSION),
-	SLE_CONDVAR(Station, dock_tile,                  SLE_FILE_U16 | SLE_VAR_U32,  SL_MIN_VERSION, SLV_6),
-	SLE_CONDVAR(Station, dock_tile,                  SLE_UINT32,                  SLV_6, SL_MAX_VERSION),
+	SLE_CONDNULL(2, SL_MIN_VERSION, SLV_6),
+	SLE_CONDNULL(4, SLV_6, SLV_MULTITILE_DOCKS),
 	    SLE_REF(Station, town,                       REF_TOWN),
 	    SLE_VAR(Station, train_station.w,            SLE_FILE_U8 | SLE_VAR_U16),
 	SLE_CONDVAR(Station, train_station.h,            SLE_FILE_U8 | SLE_VAR_U16,   SLV_2, SL_MAX_VERSION),
@@ -423,7 +423,13 @@ static const SaveLoad _station_desc[] = {
 
 	      SLE_REF(Station, bus_stops,                  REF_ROADSTOPS),
 	      SLE_REF(Station, truck_stops,                REF_ROADSTOPS),
-	      SLE_VAR(Station, dock_tile,                  SLE_UINT32),
+	 SLE_CONDNULL(4, SL_MIN_VERSION, SLV_MULTITILE_DOCKS),
+	  SLE_CONDVAR(Station, ship_station.tile,          SLE_UINT32,                SLV_MULTITILE_DOCKS, SL_MAX_VERSION),
+	  SLE_CONDVAR(Station, ship_station.w,             SLE_FILE_U8 | SLE_VAR_U16, SLV_MULTITILE_DOCKS, SL_MAX_VERSION),
+	  SLE_CONDVAR(Station, ship_station.h,             SLE_FILE_U8 | SLE_VAR_U16, SLV_MULTITILE_DOCKS, SL_MAX_VERSION),
+	  SLE_CONDVAR(Station, docking_station.tile,       SLE_UINT32,                SLV_MULTITILE_DOCKS, SL_MAX_VERSION),
+	  SLE_CONDVAR(Station, docking_station.w,          SLE_FILE_U8 | SLE_VAR_U16, SLV_MULTITILE_DOCKS, SL_MAX_VERSION),
+	  SLE_CONDVAR(Station, docking_station.h,          SLE_FILE_U8 | SLE_VAR_U16, SLV_MULTITILE_DOCKS, SL_MAX_VERSION),
 	      SLE_VAR(Station, airport.tile,               SLE_UINT32),
 	  SLE_CONDVAR(Station, airport.w,                  SLE_FILE_U8 | SLE_VAR_U16, SLV_140, SL_MAX_VERSION),
 	  SLE_CONDVAR(Station, airport.h,                  SLE_FILE_U8 | SLE_VAR_U16, SLV_140, SL_MAX_VERSION),
diff --git a/src/script/api/script_order.cpp b/src/script/api/script_order.cpp
index 04f7c69f4..a72245d04 100644
--- a/src/script/api/script_order.cpp
+++ b/src/script/api/script_order.cpp
@@ -261,8 +261,10 @@ static int ScriptOrderPositionToRealOrderPosition(VehicleID vehicle_id, ScriptOr
 				TILE_AREA_LOOP(t, st->train_station) {
 					if (st->TileBelongsToRailStation(t)) return t;
 				}
-			} else if (st->dock_tile != INVALID_TILE) {
-				return st->dock_tile;
+			} else if (st->ship_station.tile != INVALID_TILE) {
+				TILE_AREA_LOOP(t, st->ship_station) {
+					if (IsDockTile(t) && GetStationIndex(t) == st->index) return t;
+				}
 			} else if (st->bus_stops != nullptr) {
 				return st->bus_stops->xy;
 			} else if (st->truck_stops != nullptr) {
diff --git a/src/ship.h b/src/ship.h
index fff0aee5c..ef009046a 100644
--- a/src/ship.h
+++ b/src/ship.h
@@ -57,6 +57,8 @@ struct Ship FINAL : public SpecializedVehicle<Ship, VEH_SHIP> {
 	void SetDestTile(TileIndex tile);
 };
 
+bool IsShipDestinationTile(TileIndex tile, StationID station);
+
 /**
  * Iterate over all ships.
  * @param var The variable used for iteration.
diff --git a/src/ship_cmd.cpp b/src/ship_cmd.cpp
index 08b07a07d..73f2ee97f 100644
--- a/src/ship_cmd.cpp
+++ b/src/ship_cmd.cpp
@@ -34,6 +34,8 @@
 #include "tunnelbridge_map.h"
 #include "zoom_func.h"
 #include "framerate_type.h"
+#include "industry.h"
+#include "industry_map.h"
 
 #include "table/strings.h"
 
@@ -289,8 +291,8 @@ TileIndex Ship::GetOrderStationLocation(StationID station)
 	if (station == this->last_station_visited) this->last_station_visited = INVALID_STATION;
 
 	const Station *st = Station::Get(station);
-	if (st->dock_tile != INVALID_TILE) {
-		return TILE_ADD(st->dock_tile, ToTileIndexDiff(GetDockOffset(st->dock_tile)));
+	if (CanVehicleUseStation(this, st)) {
+		return st->xy;
 	} else {
 		this->IncrementRealOrderIndex();
 		return 0;
@@ -597,6 +599,28 @@ static bool ShipMoveUpDownOnLock(Ship *v)
 	return true;
 }
 
+/**
+ * Test if a tile is a docking tile for the given station.
+ * @param tile Docking tile to test.
+ * @param station Destination station.
+ * @return true iff docking tile is next to station.
+ */
+bool IsShipDestinationTile(TileIndex tile, StationID station)
+{
+	assert(IsDockingTile(tile));
+	/* Check each tile adjacent to docking tile. */
+	for (DiagDirection d = DIAGDIR_BEGIN; d != DIAGDIR_END; d++) {
+		TileIndex t = tile + TileOffsByDiagDir(d);
+		if (!IsValidTile(t)) continue;
+		if (IsDockTile(t) && GetStationIndex(t) == station) return true;
+		if (IsTileType(t, MP_INDUSTRY)) {
+			const Industry *i = Industry::GetByTile(t);
+			if (i->neutral_station != nullptr && i->neutral_station->index == station) return true;
+		}
+	}
+	return false;
+}
+
 static void ShipController(Ship *v)
 {
 	uint32 r;
@@ -665,26 +689,24 @@ static void ShipController(Ship *v)
 						UpdateVehicleTimetable(v, true);
 						v->IncrementRealOrderIndex();
 						v->current_order.MakeDummy();
-					} else {
-						/* Non-buoy orders really need to reach the tile */
-						if (v->dest_tile == gp.new_tile) {
-							if (v->current_order.IsType(OT_GOTO_DEPOT)) {
-								if ((gp.x & 0xF) == 8 && (gp.y & 0xF) == 8) {
-									VehicleEnterDepot(v);
-									return;
-								}
-							} else if (v->current_order.IsType(OT_GOTO_STATION)) {
-								v->last_station_visited = v->current_order.GetDestination();
-
-								/* Process station in the orderlist. */
-								Station *st = Station::Get(v->current_order.GetDestination());
-								if (st->facilities & FACIL_DOCK) { // ugly, ugly workaround for problem with ships able to drop off cargo at wrong stations
-									ShipArrivesAt(v, st);
-									v->BeginLoading();
-								} else { // leave stations without docks right aways
-									v->current_order.MakeLeaveStation();
-									v->IncrementRealOrderIndex();
-								}
+					} else if (v->current_order.IsType(OT_GOTO_DEPOT) &&
+						v->dest_tile == gp.new_tile) {
+						/* Depot orders really need to reach the tile */
+						if ((gp.x & 0xF) == 8 && (gp.y & 0xF) == 8) {
+							VehicleEnterDepot(v);
+							return;
+						}
+					} else if (v->current_order.IsType(OT_GOTO_STATION) && IsDockingTile(gp.new_tile)) {
+						/* Process station in the orderlist. */
+						Station *st = Station::Get(v->current_order.GetDestination());
+						if (st->docking_station.Contains(gp.new_tile) && IsShipDestinationTile(gp.new_tile, st->index)) {
+							v->last_station_visited = st->index;
+							if (st->facilities & FACIL_DOCK) { // ugly, ugly workaround for problem with ships able to drop off cargo at wrong stations
+								ShipArrivesAt(v, st);
+								v->BeginLoading();
+							} else { // leave stations without docks right aways
+								v->current_order.MakeLeaveStation();
+								v->IncrementRealOrderIndex();
 							}
 						}
 					}
diff --git a/src/station.cpp b/src/station.cpp
index 096a3c373..1d2eea4ca 100644
--- a/src/station.cpp
+++ b/src/station.cpp
@@ -71,7 +71,7 @@ Station::Station(TileIndex tile) :
 	SpecializedStation<Station, false>(tile),
 	bus_station(INVALID_TILE, 0, 0),
 	truck_station(INVALID_TILE, 0, 0),
-	dock_tile(INVALID_TILE),
+	ship_station(INVALID_TILE, 0, 0),
 	indtype(IT_INVALID),
 	time_since_load(255),
 	time_since_unload(255),
@@ -329,10 +329,10 @@ uint Station::GetCatchmentRadius() const
 		if (this->bus_stops          != nullptr)         ret = max<uint>(ret, CA_BUS);
 		if (this->truck_stops        != nullptr)         ret = max<uint>(ret, CA_TRUCK);
 		if (this->train_station.tile != INVALID_TILE) ret = max<uint>(ret, CA_TRAIN);
-		if (this->dock_tile          != INVALID_TILE) ret = max<uint>(ret, CA_DOCK);
+		if (this->ship_station.tile  != INVALID_TILE) ret = max<uint>(ret, CA_DOCK);
 		if (this->airport.tile       != INVALID_TILE) ret = max<uint>(ret, this->airport.GetSpec()->catchment);
 	} else {
-		if (this->bus_stops != nullptr || this->truck_stops != nullptr || this->train_station.tile != INVALID_TILE || this->dock_tile != INVALID_TILE || this->airport.tile != INVALID_TILE) {
+		if (this->bus_stops != nullptr || this->truck_stops != nullptr || this->train_station.tile != INVALID_TILE || this->ship_station.tile != INVALID_TILE || this->airport.tile != INVALID_TILE) {
 			ret = CA_UNMODIFIED;
 		}
 	}
diff --git a/src/station_base.h b/src/station_base.h
index a0cb2c015..1f597a289 100644
--- a/src/station_base.h
+++ b/src/station_base.h
@@ -463,8 +463,9 @@ public:
 	RoadStop *truck_stops;  ///< All the truck stops
 	TileArea truck_station; ///< Tile area the truck 'station' part covers
 
-	Airport airport;        ///< Tile area the airport covers
-	TileIndex dock_tile;    ///< The location of the dock
+	Airport airport;          ///< Tile area the airport covers
+	TileArea ship_station;    ///< Tile area the ship 'station' part covers
+	TileArea docking_station; ///< Tile area the docking tiles cover
 
 	IndustryType indtype;   ///< Industry type to get the name from
 
diff --git a/src/station_cmd.cpp b/src/station_cmd.cpp
index 9dbe356e7..a7d986676 100644
--- a/src/station_cmd.cpp
+++ b/src/station_cmd.cpp
@@ -56,6 +56,7 @@
 #include "linkgraph/linkgraph_base.h"
 #include "linkgraph/refresh.h"
 #include "widgets/station_widget.h"
+#include "tunnelbridge_map.h"
 
 #include "table/strings.h"
 
@@ -401,7 +402,7 @@ void Station::GetTileArea(TileArea *ta, StationType type) const
 
 		case STATION_DOCK:
 		case STATION_OILRIG:
-			ta->tile = this->dock_tile;
+			*ta = this->docking_station;
 			break;
 
 		default: NOT_REACHED();
@@ -1459,16 +1460,14 @@ CommandCost CmdBuildRailStation(TileIndex tile_org, DoCommandFlag flags, uint32
 	return cost;
 }
 
-static void MakeRailStationAreaSmaller(BaseStation *st)
+static TileArea MakeStationAreaSmaller(BaseStation *st, TileArea ta, bool (*func)(BaseStation *, TileIndex))
 {
-	TileArea ta = st->train_station;
-
 restart:
 
 	/* too small? */
 	if (ta.w != 0 && ta.h != 0) {
 		/* check the left side, x = constant, y changes */
-		for (uint i = 0; !st->TileBelongsToRailStation(ta.tile + TileDiffXY(0, i));) {
+		for (uint i = 0; !func(st, ta.tile + TileDiffXY(0, i));) {
 			/* the left side is unused? */
 			if (++i == ta.h) {
 				ta.tile += TileDiffXY(1, 0);
@@ -1478,7 +1477,7 @@ restart:
 		}
 
 		/* check the right side, x = constant, y changes */
-		for (uint i = 0; !st->TileBelongsToRailStation(ta.tile + TileDiffXY(ta.w - 1, i));) {
+		for (uint i = 0; !func(st, ta.tile + TileDiffXY(ta.w - 1, i));) {
 			/* the right side is unused? */
 			if (++i == ta.h) {
 				ta.w--;
@@ -1487,7 +1486,7 @@ restart:
 		}
 
 		/* check the upper side, y = constant, x changes */
-		for (uint i = 0; !st->TileBelongsToRailStation(ta.tile + TileDiffXY(i, 0));) {
+		for (uint i = 0; !func(st, ta.tile + TileDiffXY(i, 0));) {
 			/* the left side is unused? */
 			if (++i == ta.w) {
 				ta.tile += TileDiffXY(0, 1);
@@ -1497,7 +1496,7 @@ restart:
 		}
 
 		/* check the lower side, y = constant, x changes */
-		for (uint i = 0; !st->TileBelongsToRailStation(ta.tile + TileDiffXY(i, ta.h - 1));) {
+		for (uint i = 0; !func(st, ta.tile + TileDiffXY(i, ta.h - 1));) {
 			/* the left side is unused? */
 			if (++i == ta.w) {
 				ta.h--;
@@ -1508,7 +1507,28 @@ restart:
 		ta.Clear();
 	}
 
-	st->train_station = ta;
+	return ta;
+}
+
+static bool TileBelongsToRailStation(BaseStation *st, TileIndex tile)
+{
+	return st->TileBelongsToRailStation(tile);
+}
+
+static void MakeRailStationAreaSmaller(BaseStation *st)
+{
+	st->train_station = MakeStationAreaSmaller(st, st->train_station, TileBelongsToRailStation);
+}
+
+static bool TileBelongsToShipStation(BaseStation *st, TileIndex tile)
+{
+	return IsDockTile(tile) && GetStationIndex(tile) == st->index;
+}
+
+static void MakeShipStationAreaSmaller(Station *st)
+{
+	st->ship_station = MakeStationAreaSmaller(st, st->ship_station, TileBelongsToShipStation);
+	UpdateStationDockingTiles(st);
 }
 
 /**
@@ -2553,10 +2573,9 @@ CommandCost CmdBuildDock(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 	ret = BuildStationPart(&st, flags, reuse, dock_area, STATIONNAMING_DOCK);
 	if (ret.Failed()) return ret;
 
-	if (st != nullptr && st->dock_tile != INVALID_TILE) return_cmd_error(STR_ERROR_TOO_CLOSE_TO_ANOTHER_DOCK);
-
 	if (flags & DC_EXEC) {
-		st->dock_tile = tile;
+		st->ship_station.Add(tile);
+		st->ship_station.Add(tile + TileOffsByDiagDir(direction));
 		st->AddFacility(FACIL_DOCK, tile);
 
 		st->rect.BeforeAddRect(dock_area.tile, dock_area.w, dock_area.h, StationRect::ADD_TRY);
@@ -2569,6 +2588,7 @@ CommandCost CmdBuildDock(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 		Company::Get(st->owner)->infrastructure.station += 2;
 
 		MakeDock(tile, st->owner, st->index, direction, wc);
+		UpdateStationDockingTiles(st);
 
 		st->AfterStationTileSetChange(true, STATION_DOCK);
 	}
@@ -2576,6 +2596,63 @@ CommandCost CmdBuildDock(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 	return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_STATION_DOCK]);
 }
 
+void RemoveDockingTile(TileIndex t)
+{
+	for (DiagDirection d = DIAGDIR_BEGIN; d != DIAGDIR_END; d++) {
+		TileIndex tile = t + TileOffsByDiagDir(d);
+		if (!IsValidTile(tile)) continue;
+
+		if (IsTileType(tile, MP_STATION)) {
+			UpdateStationDockingTiles(Station::GetByTile(tile));
+		} else if (IsTileType(tile, MP_INDUSTRY)) {
+			UpdateStationDockingTiles(Industry::GetByTile(tile)->neutral_station);
+		}
+	}
+}
+
+/**
+ * Clear docking tile status from tiles around a removed dock, if the tile has
+ * no neighbours which would keep it as a docking tile.
+ * @param tile Ex-dock tile to check.
+ */
+void ClearDockingTilesCheckingNeighbours(TileIndex tile)
+{
+	assert(IsValidTile(tile));
+
+	/* Clear and maybe re-set docking tile */
+	for (DiagDirection d = DIAGDIR_BEGIN; d != DIAGDIR_END; d++) {
+		TileIndex docking_tile = tile + TileOffsByDiagDir(d);
+		if (!IsValidTile(docking_tile)) continue;
+
+		if (IsPossibleDockingTile(docking_tile)) {
+			SetDockingTile(docking_tile, false);
+			CheckForDockingTile(docking_tile);
+		}
+	}
+}
+
+/**
+ * Find the part of a dock that is land-based
+ * @param t Dock tile to find land part of
+ * @return tile of land part of dock
+ */
+static TileIndex FindDockLandPart(TileIndex t)
+{
+	assert(IsDockTile(t));
+
+	StationGfx gfx = GetStationGfx(t);
+	if (gfx < GFX_DOCK_BASE_WATER_PART) return t;
+
+	for (DiagDirection d = DIAGDIR_BEGIN; d != DIAGDIR_END; d++) {
+		TileIndex tile = t + TileOffsByDiagDir(d);
+		if (!IsValidTile(tile)) continue;
+		if (!IsDockTile(tile)) continue;
+		if (GetStationGfx(tile) < GFX_DOCK_BASE_WATER_PART && tile + TileOffsByDiagDir(GetDockDirection(tile)) == t) return tile;
+	}
+
+	return INVALID_TILE;
+}
+
 /**
  * Remove a dock
  * @param tile TileIndex been queried
@@ -2588,9 +2665,10 @@ static CommandCost RemoveDock(TileIndex tile, DoCommandFlag flags)
 	CommandCost ret = CheckOwnership(st->owner);
 	if (ret.Failed()) return ret;
 
-	TileIndex docking_location = TILE_ADD(st->dock_tile, ToTileIndexDiff(GetDockOffset(st->dock_tile)));
+	if (!IsDockTile(tile)) return CMD_ERROR;
 
-	TileIndex tile1 = st->dock_tile;
+	TileIndex tile1 = FindDockLandPart(tile);
+	if (tile1 == INVALID_TILE) return CMD_ERROR;
 	TileIndex tile2 = tile1 + TileOffsByDiagDir(GetDockDirection(tile1));
 
 	ret = EnsureNoVehicleOnGround(tile1);
@@ -2605,26 +2683,34 @@ static CommandCost RemoveDock(TileIndex tile, DoCommandFlag flags)
 		st->rect.AfterRemoveTile(st, tile1);
 		st->rect.AfterRemoveTile(st, tile2);
 
-		st->dock_tile = INVALID_TILE;
-		st->facilities &= ~FACIL_DOCK;
+		MakeShipStationAreaSmaller(st);
+		if (st->ship_station.tile == INVALID_TILE) {
+			st->ship_station.Clear();
+			st->docking_station.Clear();
+			st->facilities &= ~FACIL_DOCK;
+		}
 
 		Company::Get(st->owner)->infrastructure.station -= 2;
 
 		st->AfterStationTileSetChange(false, STATION_DOCK);
 
+		ClearDockingTilesCheckingNeighbours(tile1);
+		ClearDockingTilesCheckingNeighbours(tile2);
+
 		/* All ships that were going to our station, can't go to it anymore.
 		 * Just clear the order, then automatically the next appropriate order
 		 * will be selected and in case of no appropriate order it will just
 		 * wander around the world. */
-		Ship *s;
-		FOR_ALL_SHIPS(s) {
-			if (s->current_order.IsType(OT_LOADING) && s->tile == docking_location) {
-				s->LeaveStation();
-			}
+		if (!(st->facilities & FACIL_DOCK)) {
+			Ship *s;
+			FOR_ALL_SHIPS(s) {
+				if (s->current_order.IsType(OT_LOADING) && s->current_order.GetDestination() == st->index) {
+					s->LeaveStation();
+				}
 
-			if (s->dest_tile == docking_location) {
-				s->SetDestTile(0);
-				s->current_order.Free();
+				if (s->current_order.IsType(OT_GOTO_STATION) && s->current_order.GetDestination() == st->index) {
+					s->SetDestTile(s->GetOrderStationLocation(st->index));
+				}
 			}
 		}
 	}
@@ -2873,7 +2959,7 @@ draw_default_foundation:
 		} else {
 			assert(IsDock(ti->tile));
 			TileIndex water_tile = ti->tile + TileOffsByDiagDir(GetDockDirection(ti->tile));
-			WaterClass wc = GetWaterClass(water_tile);
+			WaterClass wc = HasTileWaterClass(water_tile) ? GetWaterClass(water_tile) : WATER_CLASS_INVALID;
 			if (wc == WATER_CLASS_SEA) {
 				DrawShoreTile(ti->tileh);
 			} else {
@@ -3991,6 +4077,32 @@ uint MoveGoodsToStation(CargoID type, uint amount, SourceType source_type, Sourc
 	return moved + UpdateStationWaiting(st2, type, worst_cargo, source_type, source_id);
 }
 
+void UpdateStationDockingTiles(Station *st)
+{
+	st->docking_station.Clear();
+
+	/* For neutral stations, start with the industry area instead of dock area */
+	const TileArea *area = st->industry != nullptr ? &st->industry->location : &st->ship_station;
+
+	if (area->tile == INVALID_TILE) return;
+
+	int x = TileX(area->tile);
+	int y = TileY(area->tile);
+
+	/* Expand the area by a tile on each side while
+	 * making sure that we remain inside the map. */
+	int x2 = min(x + area->w + 1, MapSizeX());
+	int x1 = max(x - 1, 0);
+
+	int y2 = min(y + area->h + 1, MapSizeY());
+	int y1 = max(y - 1, 0);
+
+	TileArea ta(TileXY(x1, y1), TileXY(x2 - 1, y2 - 1));
+	TILE_AREA_LOOP(tile, ta) {
+		if (IsValidTile(tile) && IsPossibleDockingTile(tile)) CheckForDockingTile(tile);
+	}
+}
+
 void BuildOilRig(TileIndex tile)
 {
 	if (!Station::CanAllocateItem()) {
@@ -4014,9 +4126,10 @@ void BuildOilRig(TileIndex tile)
 	st->owner = OWNER_NONE;
 	st->airport.type = AT_OILRIG;
 	st->airport.Add(tile);
-	st->dock_tile = tile;
+	st->ship_station.Add(tile);
 	st->facilities = FACIL_AIRPORT | FACIL_DOCK;
 	st->build_date = _date;
+	UpdateStationDockingTiles(st);
 
 	st->rect.BeforeAddTile(tile, StationRect::ADD_FORCE);
 
diff --git a/src/station_func.h b/src/station_func.h
index a6d082b93..44aec087f 100644
--- a/src/station_func.h
+++ b/src/station_func.h
@@ -40,6 +40,9 @@ void StationPickerDrawSprite(int x, int y, StationType st, RailType railtype, Ro
 bool HasStationInUse(StationID station, bool include_company, CompanyID company);
 
 void DeleteOilRig(TileIndex t);
+void UpdateStationDockingTiles(Station *st);
+void RemoveDockingTile(TileIndex t);
+void ClearDockingTilesCheckingNeighbours(TileIndex tile);
 
 /* Check if a rail station tile is traversable. */
 bool IsStationTileBlocked(TileIndex tile);
diff --git a/src/station_map.h b/src/station_map.h
index 35766ec69..98f8f288b 100644
--- a/src/station_map.h
+++ b/src/station_map.h
@@ -536,6 +536,7 @@ static inline void MakeStation(TileIndex t, Owner o, StationID sid, StationType
 	SetTileType(t, MP_STATION);
 	SetTileOwner(t, o);
 	SetWaterClass(t, wc);
+	SetDockingTile(t, false);
 	_m[t].m2 = sid;
 	_m[t].m3 = 0;
 	_m[t].m4 = 0;
diff --git a/src/tunnelbridge_cmd.cpp b/src/tunnelbridge_cmd.cpp
index 83cec4fd3..fce0855d2 100644
--- a/src/tunnelbridge_cmd.cpp
+++ b/src/tunnelbridge_cmd.cpp
@@ -41,6 +41,7 @@
 #include "object_base.h"
 #include "water.h"
 #include "company_gui.h"
+#include "station_func.h"
 
 #include "table/strings.h"
 #include "table/bridge_land.h"
@@ -533,6 +534,8 @@ CommandCost CmdBuildBridge(TileIndex end_tile, DoCommandFlag flags, uint32 p1, u
 				if (is_new_owner && c != nullptr) c->infrastructure.water += (bridge_len + 2) * TUNNELBRIDGE_TRACKBIT_FACTOR;
 				MakeAqueductBridgeRamp(tile_start, owner, dir);
 				MakeAqueductBridgeRamp(tile_end,   owner, ReverseDiagDir(dir));
+				CheckForDockingTile(tile_start);
+				CheckForDockingTile(tile_end);
 				break;
 
 			default:
@@ -944,6 +947,9 @@ static CommandCost DoClearBridge(TileIndex tile, DoCommandFlag flags)
 			if (v != nullptr) FreeTrainTrackReservation(v);
 		}
 
+		bool removetile = false;
+		bool removeendtile = false;
+
 		/* Update company infrastructure counts. */
 		if (rail) {
 			if (Company::IsValidID(owner)) Company::Get(owner)->infrastructure.rail[GetRailType(tile)] -= len * TUNNELBRIDGE_TRACKBIT_FACTOR;
@@ -953,11 +959,16 @@ static CommandCost DoClearBridge(TileIndex tile, DoCommandFlag flags)
 			UpdateCompanyRoadInfrastructure(GetRoadTypeTram(tile), GetRoadOwner(tile, RTT_TRAM), -(int)(len * 2 * TUNNELBRIDGE_TRACKBIT_FACTOR));
 		} else { // Aqueduct
 			if (Company::IsValidID(owner)) Company::Get(owner)->infrastructure.water -= len * TUNNELBRIDGE_TRACKBIT_FACTOR;
+			removetile    = IsDockingTile(tile);
+			removeendtile = IsDockingTile(endtile);
 		}
 		DirtyCompanyInfrastructureWindows(owner);
 
 		DoClearSquare(tile);
 		DoClearSquare(endtile);
+
+		if (removetile)    RemoveDockingTile(tile);
+		if (removeendtile) RemoveDockingTile(endtile);
 		for (TileIndex c = tile + delta; c != endtile; c += delta) {
 			/* do not let trees appear from 'nowhere' after removing bridge */
 			if (IsNormalRoadTile(c) && GetRoadside(c) == ROADSIDE_TREES) {
diff --git a/src/water.h b/src/water.h
index 1b804720f..9e2c23418 100644
--- a/src/water.h
+++ b/src/water.h
@@ -38,6 +38,7 @@ void DrawWaterClassGround(const struct TileInfo *ti);
 void DrawShoreTile(Slope tileh);
 
 void MakeWaterKeepingClass(TileIndex tile, Owner o);
+void CheckForDockingTile(TileIndex t);
 
 bool RiverModifyDesertZone(TileIndex tile, void *data);
 static const uint RIVER_OFFSET_DESERT_DISTANCE = 5; ///< Circular tile search radius to create non-desert around a river tile.
diff --git a/src/water_cmd.cpp b/src/water_cmd.cpp
index b603d7411..158bd13f0 100644
--- a/src/water_cmd.cpp
+++ b/src/water_cmd.cpp
@@ -39,6 +39,7 @@
 #include "company_base.h"
 #include "company_gui.h"
 #include "newgrf_generic.h"
+#include "industry.h"
 
 #include "table/strings.h"
 
@@ -148,6 +149,8 @@ CommandCost CmdBuildShipDepot(TileIndex tile, DoCommandFlag flags, uint32 p1, ui
 
 		MakeShipDepot(tile,  _current_company, depot->index, DEPOT_PART_NORTH, axis, wc1);
 		MakeShipDepot(tile2, _current_company, depot->index, DEPOT_PART_SOUTH, axis, wc2);
+		CheckForDockingTile(tile);
+		CheckForDockingTile(tile2);
 		MarkTileDirtyByTile(tile);
 		MarkTileDirtyByTile(tile2);
 		MakeDefaultName(depot);
@@ -156,6 +159,48 @@ CommandCost CmdBuildShipDepot(TileIndex tile, DoCommandFlag flags, uint32 p1, ui
 	return cost;
 }
 
+bool IsPossibleDockingTile(TileIndex t)
+{
+	assert(IsValidTile(t));
+	switch (GetTileType(t)) {
+		case MP_WATER:
+			if (IsLock(t) && GetLockPart(t) == LOCK_PART_MIDDLE) return false;
+			FALLTHROUGH;
+		case MP_RAILWAY:
+		case MP_STATION:
+		case MP_TUNNELBRIDGE:
+			return TrackStatusToTrackBits(GetTileTrackStatus(t, TRANSPORT_WATER, 0)) != TRACK_BIT_NONE;
+
+		default:
+			return false;
+	}
+}
+
+/**
+ * Mark the supplied tile as a docking tile if it is suitable for docking.
+ * Tiles surrounding the tile are tested to be docks with correct orientation.
+ * @param t Tile to test.
+ */
+void CheckForDockingTile(TileIndex t)
+{
+	for (DiagDirection d = DIAGDIR_BEGIN; d != DIAGDIR_END; d++) {
+		TileIndex tile = t + TileOffsByDiagDir(d);
+		if (!IsValidTile(tile)) continue;
+
+		if (IsDockTile(tile)) {
+			Station::GetByTile(tile)->docking_station.Add(t);
+			SetDockingTile(t, true);
+		}
+		if (IsTileType(tile, MP_INDUSTRY)) {
+			Station *st = Industry::GetByTile(tile)->neutral_station;
+			if (st != nullptr) {
+				st->docking_station.Add(t);
+				SetDockingTile(t, true);
+			}
+		}
+	}
+}
+
 void MakeWaterKeepingClass(TileIndex tile, Owner o)
 {
 	WaterClass wc = GetWaterClass(tile);
@@ -204,6 +249,7 @@ void MakeWaterKeepingClass(TileIndex tile, Owner o)
 		default: break;
 	}
 
+	if (wc != WATER_CLASS_INVALID) CheckForDockingTile(tile);
 	MarkTileDirtyByTile(tile);
 }
 
@@ -303,6 +349,8 @@ static CommandCost DoBuildLock(TileIndex tile, DiagDirection dir, DoCommandFlag
 		}
 
 		MakeLock(tile, _current_company, dir, wc_lower, wc_upper, wc_middle);
+		CheckForDockingTile(tile - delta);
+		CheckForDockingTile(tile + delta);
 		MarkTileDirtyByTile(tile);
 		MarkTileDirtyByTile(tile - delta);
 		MarkTileDirtyByTile(tile + delta);
@@ -449,6 +497,7 @@ CommandCost CmdBuildCanal(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 			}
 			MarkTileDirtyByTile(tile);
 			MarkCanalsAndRiversAroundDirty(tile);
+			CheckForDockingTile(tile);
 		}
 
 		cost.AddCost(_price[PR_BUILD_CANAL]);
@@ -489,8 +538,10 @@ static CommandCost ClearTile_Water(TileIndex tile, DoCommandFlag flags)
 					Company::Get(owner)->infrastructure.water--;
 					DirtyCompanyInfrastructureWindows(owner);
 				}
+				bool remove = IsDockingTile(tile);
 				DoClearSquare(tile);
 				MarkCanalsAndRiversAroundDirty(tile);
+				if (remove) RemoveDockingTile(tile);
 			}
 
 			return CommandCost(EXPENSES_CONSTRUCTION, base_cost);
@@ -504,8 +555,10 @@ static CommandCost ClearTile_Water(TileIndex tile, DoCommandFlag flags)
 			if (ret.Failed()) return ret;
 
 			if (flags & DC_EXEC) {
+				bool remove = IsDockingTile(tile);
 				DoClearSquare(tile);
 				MarkCanalsAndRiversAroundDirty(tile);
+				if (remove) RemoveDockingTile(tile);
 			}
 			if (IsSlopeWithOneCornerRaised(slope)) {
 				return CommandCost(EXPENSES_CONSTRUCTION, _price[PR_CLEAR_WATER]);
@@ -1095,6 +1148,8 @@ void DoFloodTile(TileIndex target)
 
 		/* update signals if needed */
 		UpdateSignalsInBuffer();
+
+		if (IsPossibleDockingTile(target)) CheckForDockingTile(target);
 	}
 
 	cur_company.Restore();
diff --git a/src/water_map.h b/src/water_map.h
index 5d84d5ba6..375c80e6c 100644
--- a/src/water_map.h
+++ b/src/water_map.h
@@ -69,6 +69,8 @@ enum LockPart {
 	LOCK_PART_UPPER  = 2, ///< Upper part of a lock.
 };
 
+bool IsPossibleDockingTile(TileIndex t);
+
 /**
  * Get the water tile type at a tile.
  * @param t Water tile to query.
@@ -346,6 +348,27 @@ static inline bool HasTileWaterGround(TileIndex t)
 	return HasTileWaterClass(t) && IsTileOnWater(t) && !IsCoastTile(t);
 }
 
+/**
+ * Set the docking tile state of a tile. This is used by pathfinders to reach their destination.
+ * As well as water tiles, half-rail tiles, buoys and aqueduct ends can also be docking tiles.
+ * @param t the tile
+ * @param b the docking tile state
+ */
+static inline void SetDockingTile(TileIndex t, bool b)
+{
+	assert(IsTileType(t, MP_WATER) || IsTileType(t, MP_RAILWAY) || IsTileType(t, MP_STATION) || IsTileType(t, MP_TUNNELBRIDGE));
+	SB(_m[t].m1, 7, 1, b ? 1 : 0);
+}
+
+/**
+ * Checks whether the tile is marked as a dockling tile.
+ * @return true iff the tile is marked as a docking tile.
+ */
+static inline bool IsDockingTile(TileIndex t)
+{
+	return (IsTileType(t, MP_WATER) || IsTileType(t, MP_RAILWAY) || IsTileType(t, MP_STATION) || IsTileType(t, MP_TUNNELBRIDGE)) && HasBit(_m[t].m1, 7);
+}
+
 
 /**
  * Helper function to make a coast tile.
@@ -356,6 +379,7 @@ static inline void MakeShore(TileIndex t)
 	SetTileType(t, MP_WATER);
 	SetTileOwner(t, OWNER_WATER);
 	SetWaterClass(t, WATER_CLASS_SEA);
+	SetDockingTile(t, false);
 	_m[t].m2 = 0;
 	_m[t].m3 = 0;
 	_m[t].m4 = 0;
@@ -376,6 +400,7 @@ static inline void MakeWater(TileIndex t, Owner o, WaterClass wc, uint8 random_b
 	SetTileType(t, MP_WATER);
 	SetTileOwner(t, o);
 	SetWaterClass(t, wc);
+	SetDockingTile(t, false);
 	_m[t].m2 = 0;
 	_m[t].m3 = 0;
 	_m[t].m4 = random_bits;
@@ -429,6 +454,7 @@ static inline void MakeShipDepot(TileIndex t, Owner o, DepotID did, DepotPart pa
 	SetTileType(t, MP_WATER);
 	SetTileOwner(t, o);
 	SetWaterClass(t, original_water_class);
+	SetDockingTile(t, false);
 	_m[t].m2 = did;
 	_m[t].m3 = 0;
 	_m[t].m4 = 0;
@@ -451,6 +477,7 @@ static inline void MakeLockTile(TileIndex t, Owner o, LockPart part, DiagDirecti
 	SetTileType(t, MP_WATER);
 	SetTileOwner(t, o);
 	SetWaterClass(t, original_water_class);
+	SetDockingTile(t, false);
 	_m[t].m2 = 0;
 	_m[t].m3 = 0;
 	_m[t].m4 = 0;
diff --git a/src/waypoint_cmd.cpp b/src/waypoint_cmd.cpp
index 76326a3a4..20e600b5e 100644
--- a/src/waypoint_cmd.cpp
+++ b/src/waypoint_cmd.cpp
@@ -332,6 +332,7 @@ CommandCost CmdBuildBuoy(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 		if (wp->town == nullptr) MakeDefaultName(wp);
 
 		MakeBuoy(tile, wp->index, GetWaterClass(tile));
+		CheckForDockingTile(tile);
 		MarkTileDirtyByTile(tile);
 
 		wp->UpdateVirtCoord();