--- a/misc.c	Tue Nov 22 15:55:38 2005 +0000
+++ b/misc.c	Tue Nov 22 19:33:29 2005 +0000
@@ -811,7 +811,7 @@
 
 		SlArray(buf, lengthof(buf),
 			/* In those versions the m2 was 8 bits */
-			_sl_version < 5 ? SLE_FILE_U8 | SLE_VAR_U16 : SLE_UINT16
+			CheckSavegameVersion(5) ? SLE_FILE_U8 | SLE_VAR_U16 : SLE_UINT16
 		);
 		for (j = 0; j != lengthof(buf); j++) _m[i++].m2 = buf[j];
 	}

--- a/openttd.c	Tue Nov 22 15:55:38 2005 +0000
+++ b/openttd.c	Tue Nov 22 19:33:29 2005 +0000
@@ -1130,22 +1130,22 @@
 	Player *p;
 
 	// in version 2.1 of the savegame, town owner was unified.
-	if (version <= 0x200) ConvertTownOwner();
+	if (CheckSavegameVersionOldStyle(2, 1)) ConvertTownOwner();
 
 	// from version 4.1 of the savegame, exclusive rights are stored at towns
-	if (version <= 0x400) UpdateExclusiveRights();
+	if (CheckSavegameVersionOldStyle(4, 1)) UpdateExclusiveRights();
 
 	// from version 4.2 of the savegame, currencies are in a different order
-	if (version <= 0x401) UpdateCurrencies();
+	if (CheckSavegameVersionOldStyle(4, 2)) UpdateCurrencies();
 
-	// from version 6.0 of the savegame, signs have an "owner"
-	if (version <= 0x600) UpdateSignOwner();
+	// from version 6.1 of the savegame, signs have an "owner"
+	if (CheckSavegameVersionOldStyle(6, 1)) UpdateSignOwner();
 
 	/* In old version there seems to be a problem that water is owned by
 	    OWNER_NONE, not OWNER_WATER.. I can't replicate it for the current
-	    (0x402) version, so I just check when versions are older, and then
+	    (4.3) version, so I just check when versions are older, and then
 	    walk through the whole map.. */
-	if (version <= 0x402) {
+	if (CheckSavegameVersionOldStyle(4, 3)) {
 		TileIndex tile = TileXY(0, 0);
 		uint w = MapSizeX();
 		uint h = MapSizeY();
@@ -1172,12 +1172,12 @@
 	AfterLoadVehicles();
 
 	// Update all waypoints
-	if (version < 0x0C00) FixOldWaypoints();
+	if (CheckSavegameVersion(12)) FixOldWaypoints();
 
 	UpdateAllWaypointSigns();
 
 	// in version 2.2 of the savegame, we have new airports
-	if (version <= 0x201) UpdateOldAircraft();
+	if (CheckSavegameVersionOldStyle(2, 2)) UpdateOldAircraft();
 
 	UpdateAllStationVirtCoord();
 
@@ -1205,12 +1205,12 @@
 	vp->virtual_width = vp->width << vp->zoom;
 	vp->virtual_height = vp->height << vp->zoom;
 
-	// in version 4.0 of the savegame, is_active was introduced to determine
+	// in version 4.1 of the savegame, is_active was introduced to determine
 	// if a player does exist, rather then checking name_1
-	if (version <= 0x400) CheckIsPlayerActive();
+	if (CheckSavegameVersionOldStyle(4, 1)) CheckIsPlayerActive();
 
-	// the void tiles on the southern border used to belong to a wrong class.
-	if (version <= 0x402) UpdateVoidTiles();
+	// the void tiles on the southern border used to belong to a wrong class (pre 4.3).
+	if (CheckSavegameVersionOldStyle(4, 3)) UpdateVoidTiles();
 
 	// If Load Scenario / New (Scenario) Game is used,
 	//  a player does not exist yet. So create one here.
@@ -1222,10 +1222,13 @@
 	DoZoomInOutWindow(ZOOM_NONE, w); // update button status
 	MarkWholeScreenDirty();
 
-	//In 5.1, Oilrigs have been moved (again)
-	if (version <= 0x500) UpdateOilRig();
+	// In 5.1, Oilrigs have been moved (again)
+	if (CheckSavegameVersionOldStyle(5, 1)) UpdateOilRig();
 
-	if (version <= 0x600) {
+	/* In version 6.1 we put the town index in the map-array. To do this, we need
+	 *  to use m2 (16bit big), so we need to clean m2, and that is where this is
+	 *  all about ;) */
+	if (CheckSavegameVersionOldStyle(6, 1)) {
 		BEGIN_TILE_LOOP(tile, MapSizeX(), MapSizeY(), 0) {
 			if (IsTileType(tile, MP_HOUSE)) {
 				_m[tile].m4 = _m[tile].m2;
@@ -1247,12 +1250,16 @@
 		} END_TILE_LOOP(tile, MapSizeX(), MapSizeY(), 0);
 	}
 
-	if (version < 0x900) {
+	/* From version 9.0, we update the max passengers of a town (was sometimes negative
+	 *  before that. */
+	if (CheckSavegameVersion(9)) {
 		Town *t;
 		FOR_ALL_TOWNS(t) UpdateTownMaxPass(t);
 	}
 
-	if (version < 0xF00) {
+	/* From version 15.0, we moved a semaphore bit from bit 2 to bit 3 in m4, making
+	 *  room for PBS. While doing that, clean some blocks that should be empty, for PBS. */
+	if (CheckSavegameVersion(15)) {
 		BEGIN_TILE_LOOP(tile, MapSizeX(), MapSizeY(), 0) {
 			if (IsTileType(tile, MP_RAILWAY) && HasSignals(tile) && HASBIT(_m[tile].m4, 2)) {
 				CLRBIT(_m[tile].m4, 2);
@@ -1264,7 +1271,9 @@
 		} END_TILE_LOOP(tile, MapSizeX(), MapSizeY(), 0);
 	}
 
-	if (version < 0x1000) {
+	/* From version 16.0, we included autorenew on engines, which are now saved, but
+	 *  of course, we do need to initialize them for older savegames. */
+	if (CheckSavegameVersion(16)) {
 		FOR_ALL_PLAYERS(p) {
 			EngineID i;
 
@@ -1288,7 +1297,7 @@
 	/* In version 16.1 of the savegame, trains became aware of station lengths
 		need to initialized to the invalid state
 		players needs to set renew_keep_length too */
-	if (version < 0x1001) {
+	if (CheckSavegameVersionOldStyle(16, 1)) {
 		Vehicle *v;
 		FOR_ALL_PLAYERS(p) {
 			p->renew_keep_length = false;
@@ -1306,7 +1315,7 @@
 	 * 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) {
+	if (CheckSavegameVersion(17)) {
 		Waypoint *wp;
 
 		FOR_ALL_WAYPOINTS(wp) {

--- a/order_cmd.c	Tue Nov 22 15:55:38 2005 +0000
+++ b/order_cmd.c	Tue Nov 22 19:33:29 2005 +0000
@@ -1129,13 +1129,13 @@
 
 static void Load_ORDR(void)
 {
-	if (_sl_full_version <= 0x501) {
-		/* Version older than 0x502 did not have a ->next pointer. Convert them
+	if (CheckSavegameVersionOldStyle(5, 2)) {
+		/* Version older than 5.2 did not have a ->next pointer. Convert them
 		    (in the old days, the orderlist was 5000 items big) */
 		uint len = SlGetFieldLength();
 		uint i;
 
-		if (_sl_version < 5) {
+		if (CheckSavegameVersion(5)) {
 			/* Pre-version 5 had an other layout for orders
 			    (uint16 instead of uint32) */
 			uint16 orders[5000];
@@ -1151,7 +1151,7 @@
 
 				AssignOrder(GetOrder(i), UnpackVersion4Order(orders[i]));
 			}
-		} else if (_sl_full_version <= 0x501) {
+		} else if (CheckSavegameVersionOldStyle(5, 2)) {
 			uint32 orders[5000];
 
 			len /= sizeof(uint32);

--- a/saveload.c	Tue Nov 22 15:55:38 2005 +0000
+++ b/saveload.c	Tue Nov 22 19:33:29 2005 +0000
@@ -29,14 +29,12 @@
 #include <setjmp.h>
 
 enum {
-	SAVEGAME_MAJOR_VERSION = 17,
-	SAVEGAME_MINOR_VERSION = 1,
+	SAVEGAME_VERSION = 18,
 
-	SAVEGAME_LOADABLE_VERSION = (SAVEGAME_MAJOR_VERSION << 8) + SAVEGAME_MINOR_VERSION
 };
 
-byte   _sl_version;      /// the major savegame version identifier
-uint16 _sl_full_version; /// the full version of the savegame
+uint16 _sl_version;       /// the major savegame version identifier
+byte   _sl_minor_version; /// the minor savegame version, DO NOT USE!
 
 typedef void WriterProc(uint len);
 typedef uint ReaderProc(void);
@@ -1136,7 +1134,7 @@
 {
 	/* After version 4.3 REF_VEHICLE_OLD is saved as REF_VEHICLE,
 	 * and should be loaded like that */
-	if (rt == REF_VEHICLE_OLD && _sl_full_version >= ((4 << 8) | 4))
+	if (rt == REF_VEHICLE_OLD && !CheckSavegameVersionOldStyle(4, 4))
 		rt = REF_VEHICLE;
 
 	/* No need to look up NULL pointers, just return immediately */
@@ -1312,7 +1310,7 @@
 
 	/* We have written our stuff to memory, now write it to file! */
 	hdr[0] = fmt->tag;
-	hdr[1] = TO_BE32((SAVEGAME_MAJOR_VERSION << 16) + (SAVEGAME_MINOR_VERSION << 8));
+	hdr[1] = TO_BE32(SAVEGAME_VERSION << 16);
 	if (fwrite(hdr, sizeof(hdr), 1, _sl.fh) != 1) SlError("file write failed");
 
 	if (!fmt->init_write()) SlError("cannot initialize compressor");
@@ -1426,7 +1424,7 @@
 			return AbortSaveLoad();
 		}
 
-		_sl_version = SAVEGAME_MAJOR_VERSION;
+		_sl_version = SAVEGAME_VERSION;
 
 		BeforeSaveGame();
 		SlSaveChunks();
@@ -1453,23 +1451,27 @@
 				DEBUG(misc, 0) ("Unknown savegame type, trying to load it as the buggy format.");
 				rewind(_sl.fh);
 				_sl_version = version = 0;
-				_sl_full_version = 0;
+				_sl_minor_version = 0;
 				fmt = _saveload_formats + 1; // LZO
 				break;
 			}
 
 			if (fmt->tag == hdr[0]) {
 				// check version number
-				version = TO_BE32(hdr[1]) >> 8;
+				_sl_version = version = TO_BE32(hdr[1]) >> 16;
+				/* Minor is not used anymore from version 18.0, but it is still needed
+				 *  in versions before that (4 cases) which can't be removed easy.
+				 *  Therefor it is loaded, but never saved (or, it saves a 0 in any scenario).
+				 *  So never EVER use this minor version again. -- TrueLight -- 22-11-2005 */
+				_sl_minor_version = (TO_BE32(hdr[1]) >> 8) & 0xFF;
+
+				DEBUG(misc, 1)("[Savegame] Loading savegame version %d\n", _sl_version);
 
 				/* Is the version higher than the current? */
-				if (version > SAVEGAME_LOADABLE_VERSION) {
+				if (_sl_version > SAVEGAME_VERSION) {
 					DEBUG(misc, 0) ("Savegame version invalid.");
 					return AbortSaveLoad();
 				}
-
-				_sl_version = (version >> 8);
-				_sl_full_version = version;
 				break;
 			}
 		}

--- a/saveload.h	Tue Nov 22 15:55:38 2005 +0000
+++ b/saveload.h	Tue Nov 22 19:33:29 2005 +0000
@@ -26,8 +26,8 @@
 typedef struct SaveLoadGlobVarList {
 	void *address;
 	byte conv;
-	byte from_version;
-	byte to_version;
+	uint16 from_version;
+	uint16 to_version;
 } SaveLoadGlobVarList;
 
 typedef struct {
@@ -51,8 +51,8 @@
 } SLRefType;
 
 
-extern byte   _sl_version;      /// the major savegame version identifier
-extern uint16 _sl_full_version; /// the full version of the savegame
+extern uint16 _sl_version;       /// the major savegame version identifier
+extern byte   _sl_minor_version; /// the minor savegame version, DO NOT USE!
 
 
 enum {
@@ -161,6 +161,20 @@
 /* End marker */
 #define SLE_END() {SL_END, 0, 0, 0, 0, 0}
 
+/** Checks if the savegame is below major.minor.
+ */
+static inline bool CheckSavegameVersionOldStyle(uint16 major, byte minor)
+{
+	return (_sl_version < major) || (_sl_version == major && _sl_minor_version < minor);
+}
+
+/** Checks if the savegame is below version.
+ */
+static inline bool CheckSavegameVersion(uint16 version)
+{
+	return _sl_version < version;
+}
+
 void SlSetArrayIndex(uint index);
 int SlIterateArray(void);
 void SlArray(void *array, uint length, VarType conv);

--- a/station_cmd.c	Tue Nov 22 15:55:38 2005 +0000
+++ b/station_cmd.c	Tue Nov 22 19:33:29 2005 +0000
@@ -2982,7 +2982,7 @@
 		SlObject(&st->goods[i], _goods_desc);
 
 		/* In older versions, enroute_from had 0xFF as INVALID_STATION, is now 0xFFFF */
-		if (_sl_full_version < 0x700 && st->goods[i].enroute_from == 0xFF) {
+		if (CheckSavegameVersion(7) && st->goods[i].enroute_from == 0xFF) {
 			st->goods[i].enroute_from = INVALID_STATION;
 		}
 	}
@@ -3022,8 +3022,9 @@
 			st->trainst_h = h;
 		}
 
-		if (_sl_full_version < 0x600) {
-			/* Convert old bus and truck tile to new-ones */
+		/* In older versions, we had just 1 tile for a bus/lorry, now we have more..
+		 *  convert, if needed */
+		if (CheckSavegameVersion(6)) {
 			if (st->bus_tile_obsolete != 0) {
 				st->bus_stops = AllocateRoadStop();
 				if (st->bus_stops == NULL)

--- a/texteff.c	Tue Nov 22 15:55:38 2005 +0000
+++ b/texteff.c	Tue Nov 22 19:33:29 2005 +0000
@@ -364,7 +364,8 @@
 
 static void SaveLoad_ANIT(void)
 {
-	if (_sl_version < 6) {
+	// In pre version 6, we has 16bit per tile, now we have 32bit per tile, convert it ;)
+	if (CheckSavegameVersion(6)) {
 		SlArray(_animated_tile_list, lengthof(_animated_tile_list), SLE_FILE_U16 | SLE_VAR_U32);
 	} else {
 		SlArray(_animated_tile_list, lengthof(_animated_tile_list), SLE_UINT32);

--- a/vehicle.c	Tue Nov 22 15:55:38 2005 +0000
+++ b/vehicle.c	Tue Nov 22 19:33:29 2005 +0000
@@ -2354,10 +2354,10 @@
 		SlObject(v, _veh_descs[SlReadByte()]);
 
 		/* Old savegames used 'last_station_visited = 0xFF' */
-		if (_sl_version < 5 && v->last_station_visited == 0xFF)
+		if (CheckSavegameVersion(5) && v->last_station_visited == 0xFF)
 			v->last_station_visited = INVALID_STATION;
 
-		if (_sl_version < 5) {
+		if (CheckSavegameVersion(5)) {
 			/* Convert the current_order.type (which is a mix of type and flags, because
 			    in those versions, they both were 4 bits big) to type and flags */
 			v->current_order.flags = (v->current_order.type & 0xF0) >> 4;
@@ -2366,7 +2366,7 @@
 	}
 
 	/* Check for shared order-lists (we now use pointers for that) */
-	if (_sl_full_version < 0x502) {
+	if (CheckSavegameVersionOldStyle(5, 2)) {
 		FOR_ALL_VEHICLES(v) {
 			Vehicle *u;
 
@@ -2389,7 +2389,7 @@
 	}
 
 	/* Connect front and rear engines of multiheaded trains and converts subtype to the new format */
-	if (_sl_full_version < 0x1101) {
+	if (CheckSavegameVersionOldStyle(17, 1)) {
 		ConvertOldMultiheadToNew();
 	}
 }