--- a/docs/landscape.html	Wed Nov 16 16:16:18 2005 +0000
+++ b/docs/landscape.html	Wed Nov 16 22:20:15 2005 +0000
@@ -146,10 +146,11 @@
 <br>
 <br>
 <li>m1: <a href="#OwnershipInfo">owner</a> of the depot / checkpoint</li>
+<li>m2: For waypoints, index into the array of waypoints.</li>
 <li>m3 bits 0..3 = <a href="#TrackType">track type</a></li>
 <li>m3 bit 4 = use custom sprite (valid only for the checkpoint)</li>
 <li>m3 bit 6 = track on this tile is reserved by pbs</li>
-<li>m4 = custom station id</li>
+<li>m4 bits 0..3 = ground type, as per m2 bits 0..3 for railway tiles.</li>
 </ul>
 </td></tr>
 

--- a/openttd.c	Wed Nov 16 16:16:18 2005 +0000
+++ b/openttd.c	Wed Nov 16 22:20:15 2005 +0000
@@ -1287,6 +1287,43 @@
 		}
 	}
 
+	/* In version 17, ground type is moved from m2 to m4 for depots and
+	 * waypoints to make way for storing the index in m2. The custom graphics
+	 * id which was stored in m4 is now saved as a grf/id reference in the
+	 * waypoint struct. */
+	if (version < 0x1100) {
+		Waypoint *wp;
+
+		FOR_ALL_WAYPOINTS(wp) {
+			if (wp->xy != 0 && wp->deleted == 0) {
+				const StationSpec *spec = NULL;
+
+				if (HASBIT(_m[wp->xy].m3, 4))
+					spec = GetCustomStation(STAT_CLASS_WAYP, _m[wp->xy].m4 + 1);
+
+				if (spec != NULL) {
+					wp->stat_id = _m[wp->xy].m4 + 1;
+					wp->grfid = spec->grfid;
+					wp->localidx = spec->localidx;
+				} else {
+					// No custom graphics set, so set to default.
+					wp->stat_id = 0;
+					wp->grfid = 0;
+					wp->localidx = 0;
+				}
+
+				// Move ground type bits from m2 to m4.
+				_m[wp->xy].m4 = GB(_m[wp->xy].m2, 0, 4);
+				// Store waypoint index in the tile.
+				_m[wp->xy].m2 = wp->index;
+			}
+		}
+	} else {
+		/* As of version 17, we recalculate the custom graphic ID of waypoints
+		 * from the GRF ID / station index. */
+		UpdateAllWaypointCustomGraphics();
+	}
+
 	FOR_ALL_PLAYERS(p) p->avail_railtypes = GetPlayerRailtypes(p->index);
 
 	return true;

--- a/rail_cmd.c	Wed Nov 16 16:16:18 2005 +0000
+++ b/rail_cmd.c	Wed Nov 16 22:20:15 2005 +0000
@@ -1493,7 +1493,8 @@
 
 		if (IsRailWaypoint(ti->tile) && HASBIT(_m[ti->tile].m3, 4)) {
 			// look for customization
-			const StationSpec *stat = GetCustomStation(STAT_CLASS_WAYP, _m[ti->tile].m4 + 1);
+			byte stat_id = GetWaypointByTile(ti->tile)->stat_id;
+			const StationSpec *stat = GetCustomStation(STAT_CLASS_WAYP, stat_id);
 
 			if (stat != NULL) {
 				DrawTileSeqStruct const *seq;
@@ -1535,7 +1536,7 @@
 		// adjust ground tile for desert
 		// (don't adjust for arctic depots, because snow in depots looks weird)
 		// type >= 4 means waypoints
-		if ((_m[ti->tile].m2 & RAIL_MAP2LO_GROUND_MASK) == RAIL_GROUND_ICE_DESERT && (_opt.landscape == LT_DESERT || type >= 4)) {
+		if ((_m[ti->tile].m4 & RAIL_MAP2LO_GROUND_MASK) == RAIL_GROUND_ICE_DESERT && (_opt.landscape == LT_DESERT || type >= 4)) {
 			if (image != SPR_FLAT_GRASS_TILE) {
 				image += rti->snow_offset; // tile with tracks
 			} else {
@@ -1974,7 +1975,7 @@
 	byte new_ground;
 	TrackBits rail;
 
-	old_ground = GB(_m[tile].m2, 0, 4);
+	old_ground = _m[tile].m5 & RAIL_TYPE_SPECIAL ? GB(_m[tile].m4, 0, 4) : GB(_m[tile].m2, 0, 4);
 
 	switch (_opt.landscape) {
 		case LT_HILLY:
@@ -2045,7 +2046,11 @@
 modify_me:;
 	/* tile changed? */
 	if (old_ground != new_ground) {
-		SB(_m[tile].m2, 0, 4, new_ground);
+		if (_m[tile].m5 & RAIL_TYPE_SPECIAL) {
+			SB(_m[tile].m4, 0, 4, new_ground);
+		} else {
+			SB(_m[tile].m2, 0, 4, new_ground);
+		}
 		MarkTileDirtyByTile(tile);
 	}
 }

--- a/saveload.c	Wed Nov 16 16:16:18 2005 +0000
+++ b/saveload.c	Wed Nov 16 22:20:15 2005 +0000
@@ -29,8 +29,8 @@
 #include <setjmp.h>
 
 enum {
-	SAVEGAME_MAJOR_VERSION = 16,
-	SAVEGAME_MINOR_VERSION = 1,
+	SAVEGAME_MAJOR_VERSION = 17,
+	SAVEGAME_MINOR_VERSION = 0,
 
 	SAVEGAME_LOADABLE_VERSION = (SAVEGAME_MAJOR_VERSION << 8) + SAVEGAME_MINOR_VERSION
 };

--- a/waypoint.c	Wed Nov 16 16:16:18 2005 +0000
+++ b/waypoint.c	Wed Nov 16 22:20:15 2005 +0000
@@ -63,19 +63,6 @@
 	return NULL;
 }
 
-/* Fetch a waypoint by tile */
-Waypoint *GetWaypointByTile(TileIndex tile)
-{
-	Waypoint *wp;
-
-	FOR_ALL_WAYPOINTS(wp) {
-		if (wp->xy == tile)
-			return wp;
-	}
-
-	return NULL;
-}
-
 /* Update the sign for the waypoint */
 void UpdateWaypointSign(Waypoint *wp)
 {
@@ -151,6 +138,29 @@
 	return best;
 }
 
+/**
+ * Update waypoint graphics id against saved GRFID/localidx.
+ * This is to ensure the chosen graphics are correct if GRF files are changed.
+ */
+void UpdateAllWaypointCustomGraphics(void)
+{
+	Waypoint *wp;
+
+	FOR_ALL_WAYPOINTS(wp) {
+		uint i;
+
+		if (wp->grfid == 0) continue;
+
+		for (i = 0; i < GetNumCustomStations(STAT_CLASS_WAYP); i++) {
+			const StationSpec *spec = GetCustomStation(STAT_CLASS_WAYP, i);
+			if (spec != NULL && spec->grfid == wp->grfid && spec->localidx == wp->localidx) {
+				wp->stat_id = i;
+				break;
+			}
+		}
+	}
+}
+
 /** Convert existing rail to waypoint. Eg build a waypoint station over
  * piece of rail
  * @param x,y coordinates where waypoint will be built
@@ -198,13 +208,26 @@
 	}
 
 	if (flags & DC_EXEC) {
+		const StationSpec *spec = NULL;
 		bool reserved = PBSTileReserved(tile) != 0;
-		ModifyTile(tile, MP_MAP5, RAIL_TYPE_WAYPOINT | dir);
-		if (p1 > 0) { // waypoint type 0 uses default graphics
-			// custom graphics
-			_m[tile].m3 |= 16;
-			_m[tile].m4 = (p1 - 1) & 0xff;
+		ModifyTile(tile, MP_MAP2 | MP_MAP5, wp->index, RAIL_TYPE_WAYPOINT | dir);
+
+		if (GB(p1, 0, 8) < GetNumCustomStations(STAT_CLASS_WAYP))
+			spec = GetCustomStation(STAT_CLASS_WAYP, GB(p1, 0, 8));
+
+		if (spec != NULL) {
+			SETBIT(_m[tile].m3, 4);
+			wp->stat_id = GB(p1, 0, 8);
+			wp->grfid = spec->grfid;
+			wp->localidx = spec->localidx;
+		} else {
+			// Specified custom graphics do not exist, so use default.
+			CLRBIT(_m[tile].m3, 4);
+			wp->stat_id = 0;
+			wp->grfid = 0;
+			wp->localidx = 0;
 		}
+
 		if (reserved) {
 			PBSReserveTrack(tile, dir);
 		} else {
@@ -280,8 +303,8 @@
 
 		if (justremove) {
 			bool reserved = PBSTileReserved(tile) != 0;
-			ModifyTile(tile, MP_MAP5, 1<<direction);
-			_m[tile].m3 &= ~16;
+			ModifyTile(tile, MP_MAP2_CLEAR | MP_MAP5, 1<<direction);
+			CLRBIT(_m[tile].m3, 4);
 			_m[tile].m4 = 0;
 			if (reserved) {
 				PBSReserveTrack(tile, direction);
@@ -446,8 +469,9 @@
 	SLE_VAR(Waypoint, string, SLE_UINT16),
 	SLE_VAR(Waypoint, deleted, SLE_UINT8),
 
-	SLE_CONDVAR(Waypoint, build_date, SLE_UINT16, 3, 255),
-	SLE_CONDVAR(Waypoint, stat_id, SLE_UINT8, 3, 255),
+	SLE_CONDVAR(Waypoint, build_date, SLE_UINT16,  3, 255),
+	SLE_CONDVAR(Waypoint, localidx,   SLE_UINT8,   3, 255),
+	SLE_CONDVAR(Waypoint, grfid,      SLE_UINT32, 17, 255),
 
 	SLE_END()
 };

--- a/waypoint.h	Wed Nov 16 16:16:18 2005 +0000
+++ b/waypoint.h	Wed Nov 16 22:20:15 2005 +0000
@@ -6,18 +6,21 @@
 #include "pool.h"
 
 struct Waypoint {
-	TileIndex xy;
-	uint16 index;
+	TileIndex xy;      ///< Tile of waypoint
+	uint16 index;      ///< Index of waypoint
 
-	uint16 town_index;
-	byte town_cn;          // The Nth waypoint for this town (consecutive number)
-	StringID string;       // If this is zero, town + town_cn is used for naming
+	uint16 town_index; ///< Town associated with the waypoint
+	byte town_cn;      ///< The Nth waypoint for this town (consecutive number)
+	StringID string;   ///< If this is zero (i.e. no custom name), town + town_cn is used for naming
 
-	ViewportSign sign;
-	uint16 build_date;
-	byte stat_id;
-	uint32 grfid;
-	byte deleted;          // this is a delete counter. when it reaches 0, the waypoint struct is deleted.
+	ViewportSign sign; ///< Dimensions of sign (not saved)
+	uint16 build_date; ///< Date of construction
+
+	byte stat_id;      ///< ID of waypoint within the waypoint class (not saved)
+	uint32 grfid;      ///< ID of GRF file
+	byte localidx;     ///< Index of station within GRF file
+
+	byte deleted;      ///< Delete counter. If greater than 0 then it is decremented until it reaches 0; the waypoint is then is deleted.
 };
 
 enum {
@@ -56,13 +59,24 @@
 	return (_m[tile].m5 & 0xFC) == 0xC4;
 }
 
+/**
+ * Fetch a waypoint by tile
+ * @param tile Tile of waypoint
+ * @return Waypoint
+ */
+static inline Waypoint *GetWaypointByTile(TileIndex tile)
+{
+	assert(IsTileType(tile, MP_RAILWAY) && IsRailWaypoint(tile));
+	return GetWaypoint(_m[tile].m2);
+}
+
 int32 RemoveTrainWaypoint(TileIndex tile, uint32 flags, bool justremove);
 Station *ComposeWaypointStation(TileIndex tile);
-Waypoint *GetWaypointByTile(TileIndex tile);
 void ShowRenameWaypointWindow(const Waypoint *cp);
 void DrawWaypointSprite(int x, int y, int image, RailType railtype);
 void UpdateWaypointSign(Waypoint *cp);
 void FixOldWaypoints(void);
 void UpdateAllWaypointSigns(void);
+void UpdateAllWaypointCustomGraphics(void);
 
 #endif /* WAYPOINT_H */