(svn r8231) -Fix (r8125): MP desync caused by calling Random() from station constructor. This was wrong because station constructor is called also when loading savegame and when player tries to build station when it is not sure that it will succeed (thanks Rubidium)
authorKUDr
Thu, 18 Jan 2007 09:34:44 +0000
changeset 5721 fa4e587f59f5
parent 5720 33faabcca1dd
child 5722 62abdb0d0662
(svn r8231) -Fix (r8125): MP desync caused by calling Random() from station constructor. This was wrong because station constructor is called also when loading savegame and when player tries to build station when it is not sure that it will succeed (thanks Rubidium)
src/station.cpp
src/station.h
src/station_cmd.cpp
--- a/src/station.cpp	Wed Jan 17 23:25:19 2007 +0000
+++ b/src/station.cpp	Thu Jan 18 09:34:44 2007 +0000
@@ -50,7 +50,7 @@
 
 	last_vehicle_type = VEH_Invalid;
 
-	random_bits = Random();
+	random_bits = 0; // Random() must be called when station is really built (DC_EXEC)
 	waiting_triggers = 0;
 }
 
@@ -105,6 +105,19 @@
 {
 }
 
+/** Called when new facility is built on the station. If it is the first facility
+	* it initializes also 'xy' and 'random_bits' members */
+void Station::AddFacility(byte new_facility_bit, TileIndex facil_xy)
+{
+	if (facilities == 0) {
+		xy = facil_xy;
+		random_bits = Random();
+	}
+	facilities |= new_facility_bit;
+	owner = _current_player;
+	build_date = _date;
+}
+
 void Station::MarkDirty() const
 {
 	if (sign.width_1 != 0) {
--- a/src/station.h	Wed Jan 17 23:25:19 2007 +0000
+++ b/src/station.h	Thu Jan 18 09:34:44 2007 +0000
@@ -159,6 +159,7 @@
 	void* operator new (size_t size, int st_idx);
 	void operator delete(void *p, int st_idx);
 
+	void AddFacility(byte new_facility_bit, TileIndex facil_xy);
 	void MarkDirty() const;
 	void MarkTilesDirty() const;
 	bool TileBelongsToRailStation(TileIndex tile) const;
--- a/src/station_cmd.cpp	Wed Jan 17 23:25:19 2007 +0000
+++ b/src/station_cmd.cpp	Thu Jan 18 09:34:44 2007 +0000
@@ -1000,15 +1000,11 @@
 		if (CmdFailed(ret)) return ret;
 
 		st->train_tile = finalvalues[0];
-		if (!st->facilities) st->xy = finalvalues[0];
-		st->facilities |= FACIL_TRAIN;
-		st->owner = _current_player;
+		st->AddFacility(FACIL_TRAIN, finalvalues[0]);
 
 		st->trainst_w = finalvalues[1];
 		st->trainst_h = finalvalues[2];
 
-		st->build_date = _date;
-
 		st->rect.BeforeAddRect(tile_org, w_org, h_org, StationRect::ADD_TRY);
 
 		tile_delta = (axis == AXIS_X ? TileDiffXY(1, 0) : TileDiffXY(0, 1));
@@ -1415,11 +1411,7 @@
 
 		//initialize an empty station
 		road_stop->prev = prev;
-		if (!st->facilities) st->xy = tile;
-		st->facilities |= (type) ? FACIL_TRUCK_STOP : FACIL_BUS_STOP;
-		st->owner = _current_player;
-
-		st->build_date = _date;
+		st->AddFacility((type) ? FACIL_TRUCK_STOP : FACIL_BUS_STOP, tile);
 
 		st->rect.BeforeAddTile(tile, StationRect::ADD_TRY);
 
@@ -1674,15 +1666,11 @@
 	cost += _price.build_airport * w * h;
 
 	if (flags & DC_EXEC) {
-		st->owner = _current_player;
 		st->airport_tile = tile;
-		if (!st->facilities) st->xy = tile;
-		st->facilities |= FACIL_AIRPORT;
+		st->AddFacility(FACIL_AIRPORT, tile);
 		st->airport_type = (byte)p1;
 		st->airport_flags = 0;
 
-		st->build_date = _date;
-
 		st->rect.BeforeAddRect(tile, w, h, StationRect::ADD_TRY);
 
 		/* if airport was demolished while planes were en-route to it, the
@@ -1953,11 +1941,7 @@
 
 	if (flags & DC_EXEC) {
 		st->dock_tile = tile;
-		if (!st->facilities) st->xy = tile;
-		st->facilities |= FACIL_DOCK;
-		st->owner = _current_player;
-
-		st->build_date = _date;
+		st->AddFacility(FACIL_DOCK, tile);
 
 		st->rect.BeforeAddRect(tile, _dock_w_chk[direction], _dock_h_chk[direction], StationRect::ADD_TRY);