56 files changed, 406 insertions, 314 deletions
diff --git a/Makefile b/Makefile
index d689f512e..bc30364e6 100644
--- a/Makefile
+++ b/Makefile
@@ -647,6 +647,7 @@ SRCS += command.c
 SRCS += console.c
 SRCS += console_cmds.c
 SRCS += currency.c
+SRCS += date.c
 SRCS += debug.c
 SRCS += dedicated.c
 SRCS += depot.c
diff --git a/ai/default/default.c b/ai/default/default.c
index ea1d208f3..752d2cac9 100644
--- a/ai/default/default.c
+++ b/ai/default/default.c
@@ -25,6 +25,7 @@
 #include "../../depot.h"
 #include "../../variables.h"
 #include "../../bridge.h"
+#include "../../date.h"
 #include "default.h"
 
 // remove some day perhaps?
diff --git a/ai/trolly/trolly.c b/ai/trolly/trolly.c
index 26688e965..aec49c9b8 100644
--- a/ai/trolly/trolly.c
+++ b/ai/trolly/trolly.c
@@ -35,6 +35,7 @@
 #include "../../gui.h"
 #include "../../depot.h"
 #include "../../vehicle.h"
+#include "../../date.h"
 #include "../ai.h"
 
 // This function is called after StartUp. It is the init of an AI
diff --git a/aircraft_cmd.c b/aircraft_cmd.c
index b883b51c8..65f8f7205 100644
--- a/aircraft_cmd.c
+++ b/aircraft_cmd.c
@@ -23,6 +23,7 @@
 #include "newgrf_engine.h"
 #include "newgrf_callbacks.h"
 #include "newgrf_text.h"
+#include "date.h"
 
 static bool AirportMove(Vehicle *v, const AirportFTAClass *Airport);
 static bool AirportSetBlocks(Vehicle *v, AirportFTA *current_pos, const AirportFTAClass *Airport);
diff --git a/aircraft_gui.c b/aircraft_gui.c
index 7a683f7fc..72b05f018 100644
--- a/aircraft_gui.c
+++ b/aircraft_gui.c
@@ -23,6 +23,7 @@
 #include "airport.h"
 #include "vehicle_gui.h"
 #include "newgrf_engine.h"
+#include "date.h"
 
 /**
  * Draw the purchase info details of an aircraft at a given location.
diff --git a/airport.c b/airport.c
index 401e3ac5d..e8e5ce2dd 100644
--- a/airport.c
+++ b/airport.c
@@ -8,6 +8,7 @@
 #include "macros.h"
 #include "variables.h"
 #include "airport_movement.h"
+#include "date.h"
 
 static AirportFTAClass *CountryAirport;
 static AirportFTAClass *CityAirport;
diff --git a/console_cmds.c b/console_cmds.c
index 7101961fe..f65854562 100644
--- a/console_cmds.c
+++ b/console_cmds.c
@@ -20,6 +20,7 @@
 #include "station.h"
 #include "strings.h"
 #include "screenshot.h"
+#include "date.h"
 
 #ifdef ENABLE_NETWORK
 	#include "table/strings.h"
diff --git a/currency.c b/currency.c
index 960c56d3a..8ade72211 100644
--- a/currency.c
+++ b/currency.c
@@ -6,6 +6,7 @@
 #include "news.h"
 #include "variables.h"
 #include "table/strings.h"
+#include "date.h"
 
 // exchange rate    prefix
 // |  separator        |     postfix
diff --git a/date.c b/date.c
new file mode 100644
index 000000000..b2feeaff5
--- /dev/null
+++ b/date.c
@@ -0,0 +1,303 @@
+/* $Id$ */
+
+#include "stdafx.h"
+#include "openttd.h"
+#include "date.h"
+#include "variables.h"
+#include "macros.h"
+#include "vehicle.h"
+#include "network.h"
+#include "network_data.h"
+#include "network_server.h"
+#include "functions.h"
+#include "currency.h"
+
+Year      _cur_year;
+Month     _cur_month;
+Date      _date;
+DateFract _date_fract;
+
+
+void SetDate(Date date)
+{
+	YearMonthDay ymd;
+
+	_date = date;
+	ConvertDayToYMD(&ymd, date);
+	_cur_year = ymd.year;
+	_cur_month = ymd.month;
+#ifdef ENABLE_NETWORK
+	_network_last_advertise_frame = 0;
+	_network_need_advertise = true;
+#endif /* ENABLE_NETWORK */
+}
+
+#define M(a, b) ((a << 5) | b)
+static const uint16 _month_date_from_year_day[] = {
+M(0,1),M(0,2),M(0,3),M(0,4),M(0,5),M(0,6),M(0,7),M(0,8),M(0,9),M(0,10),M(0,11),M(0,12),M(0,13),M(0,14),M(0,15),M(0,16),M(0,17),M(0,18),M(0,19),M(0,20),M(0,21),M(0,22),M(0,23),M(0,24),M(0,25),M(0,26),M(0,27),M(0,28),M(0,29),M(0,30),M(0,31),
+M(1,1),M(1,2),M(1,3),M(1,4),M(1,5),M(1,6),M(1,7),M(1,8),M(1,9),M(1,10),M(1,11),M(1,12),M(1,13),M(1,14),M(1,15),M(1,16),M(1,17),M(1,18),M(1,19),M(1,20),M(1,21),M(1,22),M(1,23),M(1,24),M(1,25),M(1,26),M(1,27),M(1,28),M(1,29),
+M(2,1),M(2,2),M(2,3),M(2,4),M(2,5),M(2,6),M(2,7),M(2,8),M(2,9),M(2,10),M(2,11),M(2,12),M(2,13),M(2,14),M(2,15),M(2,16),M(2,17),M(2,18),M(2,19),M(2,20),M(2,21),M(2,22),M(2,23),M(2,24),M(2,25),M(2,26),M(2,27),M(2,28),M(2,29),M(2,30),M(2,31),
+M(3,1),M(3,2),M(3,3),M(3,4),M(3,5),M(3,6),M(3,7),M(3,8),M(3,9),M(3,10),M(3,11),M(3,12),M(3,13),M(3,14),M(3,15),M(3,16),M(3,17),M(3,18),M(3,19),M(3,20),M(3,21),M(3,22),M(3,23),M(3,24),M(3,25),M(3,26),M(3,27),M(3,28),M(3,29),M(3,30),
+M(4,1),M(4,2),M(4,3),M(4,4),M(4,5),M(4,6),M(4,7),M(4,8),M(4,9),M(4,10),M(4,11),M(4,12),M(4,13),M(4,14),M(4,15),M(4,16),M(4,17),M(4,18),M(4,19),M(4,20),M(4,21),M(4,22),M(4,23),M(4,24),M(4,25),M(4,26),M(4,27),M(4,28),M(4,29),M(4,30),M(4,31),
+M(5,1),M(5,2),M(5,3),M(5,4),M(5,5),M(5,6),M(5,7),M(5,8),M(5,9),M(5,10),M(5,11),M(5,12),M(5,13),M(5,14),M(5,15),M(5,16),M(5,17),M(5,18),M(5,19),M(5,20),M(5,21),M(5,22),M(5,23),M(5,24),M(5,25),M(5,26),M(5,27),M(5,28),M(5,29),M(5,30),
+M(6,1),M(6,2),M(6,3),M(6,4),M(6,5),M(6,6),M(6,7),M(6,8),M(6,9),M(6,10),M(6,11),M(6,12),M(6,13),M(6,14),M(6,15),M(6,16),M(6,17),M(6,18),M(6,19),M(6,20),M(6,21),M(6,22),M(6,23),M(6,24),M(6,25),M(6,26),M(6,27),M(6,28),M(6,29),M(6,30),M(6,31),
+M(7,1),M(7,2),M(7,3),M(7,4),M(7,5),M(7,6),M(7,7),M(7,8),M(7,9),M(7,10),M(7,11),M(7,12),M(7,13),M(7,14),M(7,15),M(7,16),M(7,17),M(7,18),M(7,19),M(7,20),M(7,21),M(7,22),M(7,23),M(7,24),M(7,25),M(7,26),M(7,27),M(7,28),M(7,29),M(7,30),M(7,31),
+M(8,1),M(8,2),M(8,3),M(8,4),M(8,5),M(8,6),M(8,7),M(8,8),M(8,9),M(8,10),M(8,11),M(8,12),M(8,13),M(8,14),M(8,15),M(8,16),M(8,17),M(8,18),M(8,19),M(8,20),M(8,21),M(8,22),M(8,23),M(8,24),M(8,25),M(8,26),M(8,27),M(8,28),M(8,29),M(8,30),
+M(9,1),M(9,2),M(9,3),M(9,4),M(9,5),M(9,6),M(9,7),M(9,8),M(9,9),M(9,10),M(9,11),M(9,12),M(9,13),M(9,14),M(9,15),M(9,16),M(9,17),M(9,18),M(9,19),M(9,20),M(9,21),M(9,22),M(9,23),M(9,24),M(9,25),M(9,26),M(9,27),M(9,28),M(9,29),M(9,30),M(9,31),
+M(10,1),M(10,2),M(10,3),M(10,4),M(10,5),M(10,6),M(10,7),M(10,8),M(10,9),M(10,10),M(10,11),M(10,12),M(10,13),M(10,14),M(10,15),M(10,16),M(10,17),M(10,18),M(10,19),M(10,20),M(10,21),M(10,22),M(10,23),M(10,24),M(10,25),M(10,26),M(10,27),M(10,28),M(10,29),M(10,30),
+M(11,1),M(11,2),M(11,3),M(11,4),M(11,5),M(11,6),M(11,7),M(11,8),M(11,9),M(11,10),M(11,11),M(11,12),M(11,13),M(11,14),M(11,15),M(11,16),M(11,17),M(11,18),M(11,19),M(11,20),M(11,21),M(11,22),M(11,23),M(11,24),M(11,25),M(11,26),M(11,27),M(11,28),M(11,29),M(11,30),M(11,31),
+};
+#undef M
+
+enum {
+	ACCUM_JAN = 0,
+	ACCUM_FEB = ACCUM_JAN + 31,
+	ACCUM_MAR = ACCUM_FEB + 29,
+	ACCUM_APR = ACCUM_MAR + 31,
+	ACCUM_MAY = ACCUM_APR + 30,
+	ACCUM_JUN = ACCUM_MAY + 31,
+	ACCUM_JUL = ACCUM_JUN + 30,
+	ACCUM_AUG = ACCUM_JUL + 31,
+	ACCUM_SEP = ACCUM_AUG + 31,
+	ACCUM_OCT = ACCUM_SEP + 30,
+	ACCUM_NOV = ACCUM_OCT + 31,
+	ACCUM_DEC = ACCUM_NOV + 30,
+};
+
+static const uint16 _accum_days_for_month[] = {
+	ACCUM_JAN, ACCUM_FEB, ACCUM_MAR, ACCUM_APR,
+	ACCUM_MAY, ACCUM_JUN, ACCUM_JUL, ACCUM_AUG,
+	ACCUM_SEP, ACCUM_OCT, ACCUM_NOV, ACCUM_DEC,
+};
+
+
+void ConvertDayToYMD(YearMonthDay *ymd, Date date)
+{
+	uint yr  = date / (365 + 365 + 365 + 366);
+	uint rem = date % (365 + 365 + 365 + 366);
+	uint x;
+
+	yr *= 4;
+
+	if (rem >= 366) {
+		rem--;
+		do {
+			rem -= 365;
+			yr++;
+		} while (rem >= 365);
+		if (rem >= 31 + 28) rem++;
+	}
+
+	ymd->year = yr;
+
+	x = _month_date_from_year_day[rem];
+	ymd->month = x >> 5;
+	ymd->day = x & 0x1F;
+}
+
+/**
+ * Converts a tupe of Year, Month and Day to a Date.
+ * @param year  is a number between 0..?
+ * @param month is a number between 0..11
+ * @param day   is a number between 1..31
+ */
+uint ConvertYMDToDay(Year year, Month month, Day day)
+{
+	uint rem;
+
+	/* day in the year */
+	rem = _accum_days_for_month[month] + day - 1;
+
+	/* remove feb 29 from year 1,2,3 */
+	if (year & 3) rem += (year & 3) * 365 + (rem < 31 + 29);
+
+	/* base date. */
+	return (year >> 2) * (365 + 365 + 365 + 366) + rem;
+}
+
+/**
+ * Convert a date on the form:
+ * 1920 - 2090 (MAX_YEAR_END_REAL)
+ * 192001 - 209012
+ * 19200101 - 20901231
+ * or if > 2090 and below 65536, treat it as a daycount.
+ * @return -1 if no conversion was possible
+ */
+Date ConvertIntDate(uint date)
+{
+	Year  year;
+	Month month = 0;
+	Day   day   = 1;
+
+	if (IS_INT_INSIDE(date, 1920, MAX_YEAR_END_REAL + 1)) {
+		year = date - 1920;
+	} else if (IS_INT_INSIDE(date, 192001, 209012 + 1)) {
+		month = date % 100 - 1;
+		year = date / 100 - 1920;
+	} else if (IS_INT_INSIDE(date, 19200101, 20901231 + 1)) {
+		day = date % 100; date /= 100;
+		month = date % 100 - 1;
+		year = date / 100 - 1920;
+	} else if (IS_INT_INSIDE(date, 2091, 65536)) {
+		return date;
+	} else {
+		return (Date)-1;
+	}
+
+	/* invalid ranges? */
+	if (month >= 12 || !IS_INT_INSIDE(day, 1, 31 + 1)) return (Date)-1;
+
+	return ConvertYMDToDay(year, month, day);
+}
+
+
+/** Functions used by the IncreaseDate function */
+
+extern void OnNewDay_Train(Vehicle *v);
+extern void OnNewDay_RoadVeh(Vehicle *v);
+extern void OnNewDay_Aircraft(Vehicle *v);
+extern void OnNewDay_Ship(Vehicle *v);
+static void OnNewDay_EffectVehicle(Vehicle *v) { /* empty */ }
+extern void OnNewDay_DisasterVehicle(Vehicle *v);
+
+typedef void OnNewVehicleDayProc(Vehicle *v);
+
+static OnNewVehicleDayProc * _on_new_vehicle_day_proc[] = {
+	OnNewDay_Train,
+	OnNewDay_RoadVeh,
+	OnNewDay_Ship,
+	OnNewDay_Aircraft,
+	OnNewDay_EffectVehicle,
+	OnNewDay_DisasterVehicle,
+};
+
+extern void WaypointsDailyLoop(void);
+extern void TextMessageDailyLoop(void);
+extern void EnginesDailyLoop(void);
+extern void DisasterDailyLoop(void);
+
+extern void PlayersMonthlyLoop(void);
+extern void EnginesMonthlyLoop(void);
+extern void TownsMonthlyLoop(void);
+extern void IndustryMonthlyLoop(void);
+extern void StationMonthlyLoop(void);
+
+extern void PlayersYearlyLoop(void);
+extern void TrainsYearlyLoop(void);
+extern void RoadVehiclesYearlyLoop(void);
+extern void AircraftYearlyLoop(void);
+extern void ShipsYearlyLoop(void);
+
+extern void ShowEndGameChart(void);
+
+
+static const Month _autosave_months[] = {
+	 0, // never
+	 1, // every month
+	 3, // every 3 months
+	 6, // every 6 months
+	12, // every 12 months
+};
+
+/**
+ * Runs the day_proc for every DAY_TICKS vehicle starting at daytick.
+ */
+static void RunVehicleDayProc(uint daytick)
+{
+	uint total = _vehicle_pool.total_items;
+	uint i;
+
+	for (i = daytick; i < total; i += DAY_TICKS) {
+		Vehicle *v = GetVehicle(i);
+
+		if (v->type != 0) _on_new_vehicle_day_proc[v->type - 0x10](v);
+	}
+}
+
+void IncreaseDate(void)
+{
+	YearMonthDay ymd;
+
+	if (_game_mode == GM_MENU) {
+		_tick_counter++;
+		return;
+	}
+
+	RunVehicleDayProc(_date_fract);
+
+	/* increase day, and check if a new day is there? */
+	_tick_counter++;
+
+	_date_fract++;
+	if (_date_fract < DAY_TICKS) return;
+	_date_fract = 0;
+
+	/* yeah, increase day counter and call various daily loops */
+	_date++;
+
+	TextMessageDailyLoop();
+
+	DisasterDailyLoop();
+	WaypointsDailyLoop();
+
+	if (_game_mode != GM_MENU) {
+		InvalidateWindowWidget(WC_STATUS_BAR, 0, 0);
+		EnginesDailyLoop();
+	}
+
+	/* check if we entered a new month? */
+	ConvertDayToYMD(&ymd, _date);
+	if (ymd.month == _cur_month) return;
+	_cur_month = ymd.month;
+
+	/* yes, call various monthly loops */
+	if (_game_mode != GM_MENU) {
+		if (_opt.autosave != 0 && (_cur_month % _autosave_months[_opt.autosave]) == 0) {
+			_do_autosave = true;
+			RedrawAutosave();
+		}
+
+		PlayersMonthlyLoop();
+		EnginesMonthlyLoop();
+		TownsMonthlyLoop();
+		IndustryMonthlyLoop();
+		StationMonthlyLoop();
+#ifdef ENABLE_NETWORK
+		if (_network_server) NetworkServerMonthlyLoop();
+#endif /* ENABLE_NETWORK */
+	}
+
+	/* check if we entered a new year? */
+	if (ymd.year == _cur_year) return;
+	_cur_year = ymd.year;
+
+	/* yes, call various yearly loops */
+	PlayersYearlyLoop();
+	TrainsYearlyLoop();
+	RoadVehiclesYearlyLoop();
+	AircraftYearlyLoop();
+	ShipsYearlyLoop();
+#ifdef ENABLE_NETWORK
+	if (_network_server) NetworkServerYearlyLoop();
+#endif /* ENABLE_NETWORK */
+
+	/* check if we reached end of the game */
+	if (_cur_year == _patches.ending_date - MAX_YEAR_BEGIN_REAL) {
+			ShowEndGameChart();
+	/* check if we reached the maximum year, decrement dates by a year */
+	} else if (_cur_year == (MAX_YEAR_END + 1)) {
+		Vehicle *v;
+
+		_cur_year = MAX_YEAR_END;
+		_date -= 365;
+		FOR_ALL_VEHICLES(v) {
+			v->date_of_last_service -= 365;
+		}
+
+		/* Because the _date wraps here, and text-messages expire by game-days, we have to clean out
+		 *  all of them if the date is set back, else those messages will hang for ever */
+		InitTextMessage();
+	}
+
+	if (_patches.auto_euro) CheckSwitchToEuro();
+}
diff --git a/date.h b/date.h
new file mode 100644
index 000000000..96fa2799a
--- /dev/null
+++ b/date.h
@@ -0,0 +1,35 @@
+/* $Id$ */
+
+/**
+ * 1 day is 74 ticks; _date_fract used to be uint16 and incremented by 885. On
+ *                    an overflow the new day begun and 65535 / 885 = 74.
+ * 1 tick is approximately 30 ms.
+ * 1 day is thus about 2 seconds (74 * 30 = 2220) on a machine that can run OpenTTD normally
+ */
+#define DAY_TICKS 74
+
+#define MAX_YEAR_BEGIN_REAL 1920
+#define MAX_YEAR_END_REAL 2090
+#define MAX_YEAR_END 170
+
+/* Year and Date are defined elsewhere */
+typedef uint8  Month;
+typedef uint8  Day;
+typedef uint16 DateFract;
+
+typedef struct YearMonthDay {
+	Year  year;
+	Month month;
+	Day   day;
+} YearMonthDay;
+
+extern Year      _cur_year;
+extern Month     _cur_month;
+extern Date      _date;
+extern DateFract _date_fract;
+
+
+void SetDate(Date date);
+void ConvertDayToYMD(YearMonthDay *ymd, Date date);
+uint ConvertYMDToDay(Year year, Month month, Day day);
+Date ConvertIntDate(uint date);
diff --git a/disaster_cmd.c b/disaster_cmd.c
index f34b1446f..931914695 100644
--- a/disaster_cmd.c
+++ b/disaster_cmd.c
@@ -20,6 +20,7 @@
 #include "sound.h"
 #include "variables.h"
 #include "table/sprites.h"
+#include "date.h"
 
 static void DisasterClearSquare(TileIndex tile)
 {
diff --git a/economy.c b/economy.c
index 9794adb29..ab3a3efb6 100644
--- a/economy.c
+++ b/economy.c
@@ -29,6 +29,7 @@
 #include "train.h"
 #include "newgrf_engine.h"
 #include "unmovable.h"
+#include "date.h"
 
 // Score info
 const ScoreInfo _score_info[] = {
diff --git a/engine.c b/engine.c
index 1d66b89ff..3cde8c7f6 100644
--- a/engine.c
+++ b/engine.c
@@ -16,6 +16,7 @@
 #include "variables.h"
 #include "train.h"
 #include "newgrf_cargo.h"
+#include "date.h"
 
 EngineInfo _engine_info[TOTAL_NUM_ENGINES];
 RailVehicleInfo _rail_vehicle_info[NUM_TRAIN_ENGINES];
diff --git a/functions.h b/functions.h
index bc1c6601d..a108d5f83 100644
--- a/functions.h
+++ b/functions.h
@@ -108,7 +108,6 @@ static inline TileIndex RandomTile(void) { return TILE_MASK(Random()); }
 uint32 InteractiveRandom(void); /* Used for random sequences that are not the same on the other end of the multiplayer link */
 uint InteractiveRandomRange(uint max);
 
-void SetDate(uint date);
 /* facedraw.c */
 void DrawPlayerFace(uint32 face, int color, int x, int y);
 
@@ -122,7 +121,6 @@ void InitTextMessage(void);
 void DrawTextMessage(void);
 void CDECL AddTextMessage(uint16 color, uint8 duration, const char *message, ...);
 void UndrawTextMessage(void);
-void TextMessageDailyLoop(void);
 
 bool AddAnimatedTile(TileIndex tile);
 void DeleteAnimatedTile(TileIndex tile);
@@ -163,9 +161,6 @@ char *GetName(int id, char *buff);
 #define AllocateNameUnique(name, skip) RealAllocateName(name, skip, true)
 #define AllocateName(name, skip) RealAllocateName(name, skip, false)
 StringID RealAllocateName(const char *name, byte skip, bool check_double);
-void ConvertDayToYMD(YearMonthDay *ymd, uint16 date);
-uint ConvertYMDToDay(uint year, uint month, uint day);
-uint ConvertIntDate(uint date);
 
 /* misc functions */
 void MarkTileDirty(int x, int y);
@@ -205,7 +200,6 @@ void ShowNetworkNeedGamePassword(void);
 void ShowNetworkNeedCompanyPassword(void);
 int FindFirstBit(uint32 x);
 void ShowHighscoreTable(int difficulty, int8 rank);
-void ShowEndGameChart(void);
 TileIndex AdjustTileCoordRandomly(TileIndex a, byte rng);
 
 void AfterLoadTown(void);
diff --git a/graph_gui.c b/graph_gui.c
index a7c400402..9382d7172 100644
--- a/graph_gui.c
+++ b/graph_gui.c
@@ -14,6 +14,7 @@
 #include "strings.h"
 #include "debug.h"
 #include "variables.h"
+#include "date.h"
 
 static uint _legend_excludebits;
 static uint _legend_cargobits;
diff --git a/industry_cmd.c b/industry_cmd.c
index dfc366c6f..b140be9c9 100644
--- a/industry_cmd.c
+++ b/industry_cmd.c
@@ -22,6 +22,7 @@
 #include "variables.h"
 #include "table/industry_land.h"
 #include "table/build_industry.h"
+#include "date.h"
 
 enum {
 	/* Max industries: 64000 (8 * 8000) */
diff --git a/main_gui.c b/main_gui.c
index 581bfe8e8..f9f81c299 100644
--- a/main_gui.c
+++ b/main_gui.c
@@ -29,14 +29,15 @@
 #include "train.h"
 #include "unmovable_map.h"
 #include "screenshot.h"
+#include "date.h"
 
 #include "network_data.h"
 #include "network_client.h"
 #include "network_server.h"
 
 /* Min/Max date for scenario editor */
-static const uint MinDate = 0;     // 1920-01-01 (MAX_YEAR_BEGIN_REAL)
-static const uint MaxDate = 29220; // 2000-01-01
+static const Date MinDate = 0;     // 1920-01-01 (MAX_YEAR_BEGIN_REAL)
+static const Date MaxDate = 29220; // 2000-01-01
 
 static int _rename_id;
 static int _rename_what;
diff --git a/misc.c b/misc.c
index 71e9e25fa..10e71b412 100644
--- a/misc.c
+++ b/misc.c
@@ -12,14 +12,12 @@
 #include "map.h"
 #include "vehicle.h"
 #include "saveload.h"
-#include "network.h"
-#include "network_data.h"
-#include "network_server.h"
 #include "engine.h"
 #include "vehicle_gui.h"
 #include "variables.h"
 #include "ai/ai.h"
 #include "table/landscape_const.h"
+#include "date.h"
 
 extern void StartupEconomy(void);
 
@@ -76,20 +74,6 @@ uint InteractiveRandomRange(uint max)
 	return GB(InteractiveRandom(), 0, 16) * max >> 16;
 }
 
-void SetDate(uint date)
-{
-	YearMonthDay ymd;
-
-	_date = date;
-	ConvertDayToYMD(&ymd, date);
-	_cur_year = ymd.year;
-	_cur_month = ymd.month;
-#ifdef ENABLE_NETWORK
-	_network_last_advertise_frame = 0;
-	_network_need_advertise = true;
-#endif /* ENABLE_NETWORK */
-}
-
 void InitializeVehicles(void);
 void InitializeWaypoints(void);
 void InitializeDepot(void);
@@ -277,119 +261,6 @@ StringID RealAllocateName(const char *name, byte skip, bool check_double)
 	}
 }
 
-
-#define M(a,b) ((a<<5)|b)
-static const uint16 _month_date_from_year_day[] = {
-M(0,1),M(0,2),M(0,3),M(0,4),M(0,5),M(0,6),M(0,7),M(0,8),M(0,9),M(0,10),M(0,11),M(0,12),M(0,13),M(0,14),M(0,15),M(0,16),M(0,17),M(0,18),M(0,19),M(0,20),M(0,21),M(0,22),M(0,23),M(0,24),M(0,25),M(0,26),M(0,27),M(0,28),M(0,29),M(0,30),M(0,31),
-M(1,1),M(1,2),M(1,3),M(1,4),M(1,5),M(1,6),M(1,7),M(1,8),M(1,9),M(1,10),M(1,11),M(1,12),M(1,13),M(1,14),M(1,15),M(1,16),M(1,17),M(1,18),M(1,19),M(1,20),M(1,21),M(1,22),M(1,23),M(1,24),M(1,25),M(1,26),M(1,27),M(1,28),M(1,29),
-M(2,1),M(2,2),M(2,3),M(2,4),M(2,5),M(2,6),M(2,7),M(2,8),M(2,9),M(2,10),M(2,11),M(2,12),M(2,13),M(2,14),M(2,15),M(2,16),M(2,17),M(2,18),M(2,19),M(2,20),M(2,21),M(2,22),M(2,23),M(2,24),M(2,25),M(2,26),M(2,27),M(2,28),M(2,29),M(2,30),M(2,31),
-M(3,1),M(3,2),M(3,3),M(3,4),M(3,5),M(3,6),M(3,7),M(3,8),M(3,9),M(3,10),M(3,11),M(3,12),M(3,13),M(3,14),M(3,15),M(3,16),M(3,17),M(3,18),M(3,19),M(3,20),M(3,21),M(3,22),M(3,23),M(3,24),M(3,25),M(3,26),M(3,27),M(3,28),M(3,29),M(3,30),
-M(4,1),M(4,2),M(4,3),M(4,4),M(4,5),M(4,6),M(4,7),M(4,8),M(4,9),M(4,10),M(4,11),M(4,12),M(4,13),M(4,14),M(4,15),M(4,16),M(4,17),M(4,18),M(4,19),M(4,20),M(4,21),M(4,22),M(4,23),M(4,24),M(4,25),M(4,26),M(4,27),M(4,28),M(4,29),M(4,30),M(4,31),
-M(5,1),M(5,2),M(5,3),M(5,4),M(5,5),M(5,6),M(5,7),M(5,8),M(5,9),M(5,10),M(5,11),M(5,12),M(5,13),M(5,14),M(5,15),M(5,16),M(5,17),M(5,18),M(5,19),M(5,20),M(5,21),M(5,22),M(5,23),M(5,24),M(5,25),M(5,26),M(5,27),M(5,28),M(5,29),M(5,30),
-M(6,1),M(6,2),M(6,3),M(6,4),M(6,5),M(6,6),M(6,7),M(6,8),M(6,9),M(6,10),M(6,11),M(6,12),M(6,13),M(6,14),M(6,15),M(6,16),M(6,17),M(6,18),M(6,19),M(6,20),M(6,21),M(6,22),M(6,23),M(6,24),M(6,25),M(6,26),M(6,27),M(6,28),M(6,29),M(6,30),M(6,31),
-M(7,1),M(7,2),M(7,3),M(7,4),M(7,5),M(7,6),M(7,7),M(7,8),M(7,9),M(7,10),M(7,11),M(7,12),M(7,13),M(7,14),M(7,15),M(7,16),M(7,17),M(7,18),M(7,19),M(7,20),M(7,21),M(7,22),M(7,23),M(7,24),M(7,25),M(7,26),M(7,27),M(7,28),M(7,29),M(7,30),M(7,31),
-M(8,1),M(8,2),M(8,3),M(8,4),M(8,5),M(8,6),M(8,7),M(8,8),M(8,9),M(8,10),M(8,11),M(8,12),M(8,13),M(8,14),M(8,15),M(8,16),M(8,17),M(8,18),M(8,19),M(8,20),M(8,21),M(8,22),M(8,23),M(8,24),M(8,25),M(8,26),M(8,27),M(8,28),M(8,29),M(8,30),
-M(9,1),M(9,2),M(9,3),M(9,4),M(9,5),M(9,6),M(9,7),M(9,8),M(9,9),M(9,10),M(9,11),M(9,12),M(9,13),M(9,14),M(9,15),M(9,16),M(9,17),M(9,18),M(9,19),M(9,20),M(9,21),M(9,22),M(9,23),M(9,24),M(9,25),M(9,26),M(9,27),M(9,28),M(9,29),M(9,30),M(9,31),
-M(10,1),M(10,2),M(10,3),M(10,4),M(10,5),M(10,6),M(10,7),M(10,8),M(10,9),M(10,10),M(10,11),M(10,12),M(10,13),M(10,14),M(10,15),M(10,16),M(10,17),M(10,18),M(10,19),M(10,20),M(10,21),M(10,22),M(10,23),M(10,24),M(10,25),M(10,26),M(10,27),M(10,28),M(10,29),M(10,30),
-M(11,1),M(11,2),M(11,3),M(11,4),M(11,5),M(11,6),M(11,7),M(11,8),M(11,9),M(11,10),M(11,11),M(11,12),M(11,13),M(11,14),M(11,15),M(11,16),M(11,17),M(11,18),M(11,19),M(11,20),M(11,21),M(11,22),M(11,23),M(11,24),M(11,25),M(11,26),M(11,27),M(11,28),M(11,29),M(11,30),M(11,31),
-};
-#undef M
-
-enum {
-	ACCUM_JAN = 0,
-	ACCUM_FEB = ACCUM_JAN + 31,
-	ACCUM_MAR = ACCUM_FEB + 29,
-	ACCUM_APR = ACCUM_MAR + 31,
-	ACCUM_MAY = ACCUM_APR + 30,
-	ACCUM_JUN = ACCUM_MAY + 31,
-	ACCUM_JUL = ACCUM_JUN + 30,
-	ACCUM_AUG = ACCUM_JUL + 31,
-	ACCUM_SEP = ACCUM_AUG + 31,
-	ACCUM_OCT = ACCUM_SEP + 30,
-	ACCUM_NOV = ACCUM_OCT + 31,
-	ACCUM_DEC = ACCUM_NOV + 30,
-};
-
-static const uint16 _accum_days_for_month[] = {
-	ACCUM_JAN,ACCUM_FEB,ACCUM_MAR,ACCUM_APR,
-	ACCUM_MAY,ACCUM_JUN,ACCUM_JUL,ACCUM_AUG,
-	ACCUM_SEP,ACCUM_OCT,ACCUM_NOV,ACCUM_DEC,
-};
-
-
-void ConvertDayToYMD(YearMonthDay *ymd, uint16 date)
-{
-	uint yr = date / (365+365+365+366);
-	uint rem = date % (365+365+365+366);
-	uint x;
-
-	yr *= 4;
-
-	if (rem >= 366) {
-		rem--;
-		do {
-			rem -= 365;
-			yr++;
-		} while (rem >= 365);
-		if (rem >= 31+28) rem++;
-	}
-
-	ymd->year = yr;
-
-	x = _month_date_from_year_day[rem];
-	ymd->month = x >> 5;
-	ymd->day = x & 0x1F;
-}
-
-// year is a number between 0..?
-// month is a number between 0..11
-// day is a number between 1..31
-uint ConvertYMDToDay(uint year, uint month, uint day)
-{
-	uint rem;
-
-	// day in the year
-	rem = _accum_days_for_month[month] + day - 1;
-
-	// remove feb 29 from year 1,2,3
-	if (year & 3) rem += (year & 3) * 365 + (rem < 31+29);
-
-	// base date.
-	return (year >> 2) * (365+365+365+366) + rem;
-}
-
-// convert a date on the form
-// 1920 - 2090 (MAX_YEAR_END_REAL)
-// 192001 - 209012
-// 19200101 - 20901231
-// or if > 2090 and below 65536, treat it as a daycount
-// returns -1 if no conversion was possible
-uint ConvertIntDate(uint date)
-{
-	uint year, month = 0, day = 1;
-
-	if (IS_INT_INSIDE(date, 1920, MAX_YEAR_END_REAL + 1)) {
-		year = date - 1920;
-	} else if (IS_INT_INSIDE(date, 192001, 209012+1)) {
-		month = date % 100 - 1;
-		year = date / 100 - 1920;
-	} else if (IS_INT_INSIDE(date, 19200101, 20901231+1)) {
-		day = date % 100; date /= 100;
-		month = date % 100 - 1;
-		year = date / 100 - 1920;
-	} else if (IS_INT_INSIDE(date, 2091, 65536)) {
-		return date;
-	} else {
-		return (uint)-1;
-	}
-
-	// invalid ranges?
-	if (month >= 12 || !IS_INT_INSIDE(day, 1, 31+1)) return (uint)-1;
-
-	return ConvertYMDToDay(year, month, day);
-}
-
-
 // Calculate constants that depend on the landscape type.
 void InitializeLandscapeVariables(bool only_constants)
 {
@@ -422,156 +293,6 @@ void InitializeLandscapeVariables(bool only_constants)
 }
 
 
-void OnNewDay_Train(Vehicle *v);
-void OnNewDay_RoadVeh(Vehicle *v);
-void OnNewDay_Aircraft(Vehicle *v);
-void OnNewDay_Ship(Vehicle *v);
-static void OnNewDay_EffectVehicle(Vehicle *v) { /* empty */ }
-void OnNewDay_DisasterVehicle(Vehicle *v);
-
-typedef void OnNewVehicleDayProc(Vehicle *v);
-
-static OnNewVehicleDayProc * _on_new_vehicle_day_proc[] = {
-	OnNewDay_Train,
-	OnNewDay_RoadVeh,
-	OnNewDay_Ship,
-	OnNewDay_Aircraft,
-	OnNewDay_EffectVehicle,
-	OnNewDay_DisasterVehicle,
-};
-
-void EnginesDailyLoop(void);
-void DisasterDailyLoop(void);
-void PlayersMonthlyLoop(void);
-void EnginesMonthlyLoop(void);
-void TownsMonthlyLoop(void);
-void IndustryMonthlyLoop(void);
-void StationMonthlyLoop(void);
-
-void PlayersYearlyLoop(void);
-void TrainsYearlyLoop(void);
-void RoadVehiclesYearlyLoop(void);
-void AircraftYearlyLoop(void);
-void ShipsYearlyLoop(void);
-
-void WaypointsDailyLoop(void);
-
-
-static const uint16 _autosave_months[] = {
-	0, // never
-	0xFFF, // every month
-	0x249, // every 3 months
-	0x041, // every 6 months
-	0x001, // every 12 months
-};
-
-/**
- * Runs the day_proc for every DAY_TICKS vehicle starting at daytick.
- */
-static void RunVehicleDayProc(uint daytick)
-{
-	uint total = _vehicle_pool.total_items;
-	uint i;
-
-	for (i = daytick; i < total; i += DAY_TICKS) {
-		Vehicle* v = GetVehicle(i);
-
-		if (v->type != 0) _on_new_vehicle_day_proc[v->type - 0x10](v);
-	}
-}
-
-void IncreaseDate(void)
-{
-	YearMonthDay ymd;
-
-	if (_game_mode == GM_MENU) {
-		_tick_counter++;
-		return;
-	}
-
-	RunVehicleDayProc(_date_fract);
-
-	/* increase day, and check if a new day is there? */
-	_tick_counter++;
-
-	_date_fract++;
-	if (_date_fract < DAY_TICKS) return;
-	_date_fract = 0;
-
-	/* yeah, increse day counter and call various daily loops */
-	_date++;
-
-	TextMessageDailyLoop();
-
-	DisasterDailyLoop();
-	WaypointsDailyLoop();
-
-	if (_game_mode != GM_MENU) {
-		InvalidateWindowWidget(WC_STATUS_BAR, 0, 0);
-		EnginesDailyLoop();
-	}
-
-	/* check if we entered a new month? */
-	ConvertDayToYMD(&ymd, _date);
-	if ((byte)ymd.month == _cur_month)
-		return;
-	_cur_month = ymd.month;
-
-	/* yes, call various monthly loops */
-	if (_game_mode != GM_MENU) {
-		if (HASBIT(_autosave_months[_opt.autosave], _cur_month)) {
-			_do_autosave = true;
-			RedrawAutosave();
-		}
-
-		PlayersMonthlyLoop();
-		EnginesMonthlyLoop();
-		TownsMonthlyLoop();
-		IndustryMonthlyLoop();
-		StationMonthlyLoop();
-#ifdef ENABLE_NETWORK
-		if (_network_server) NetworkServerMonthlyLoop();
-#endif /* ENABLE_NETWORK */
-	}
-
-	/* check if we entered a new year? */
-	if ((byte)ymd.year == _cur_year)
-		return;
-	_cur_year = ymd.year;
-
-	/* yes, call various yearly loops */
-
-	PlayersYearlyLoop();
-	TrainsYearlyLoop();
-	RoadVehiclesYearlyLoop();
-	AircraftYearlyLoop();
-	ShipsYearlyLoop();
-#ifdef ENABLE_NETWORK
-	if (_network_server) NetworkServerYearlyLoop();
-#endif /* ENABLE_NETWORK */
-
-	/* check if we reached end of the game (31 dec 2050) */
-	if (_cur_year == _patches.ending_date - MAX_YEAR_BEGIN_REAL) {
-			ShowEndGameChart();
-	/* check if we reached 2090 (MAX_YEAR_END_REAL), that's the maximum year. */
-	} else if (_cur_year == (MAX_YEAR_END + 1)) {
-		Vehicle* v;
-
-		_cur_year = MAX_YEAR_END;
-		_date = 62093;
-		FOR_ALL_VEHICLES(v) {
-			v->date_of_last_service -= 365; // 1 year is 365 days long
-		}
-
-		/* Because the _date wraps here, and text-messages expire by game-days, we have to clean out
-		 *  all of them if the date is set back, else those messages will hang for ever */
-		InitTextMessage();
-	}
-
-	if (_patches.auto_euro) CheckSwitchToEuro();
-
-	/* XXX: check if year 2050 was reached */
-}
 
 int FindFirstBit(uint32 value)
 {
diff --git a/misc_gui.c b/misc_gui.c
index dd8af7368..8a7c4954e 100644
--- a/misc_gui.c
+++ b/misc_gui.c
@@ -26,6 +26,7 @@
 #include "variables.h"
 #include "vehicle.h"
 #include "train.h"
+#include "date.h"
 
 #include "fios.h"
 /* Variables to display file lists */
diff --git a/network.c b/network.c
index d08ce3c97..31743ebb6 100644
--- a/network.c
+++ b/network.c
@@ -10,6 +10,7 @@
 #include "network_data.h"
 #include "command.h"
 #include "variables.h"
+#include "date.h"
 
 #if defined(WITH_REV)
 	extern const char _openttd_revision[];
diff --git a/network_client.c b/network_client.c
index e1390568e..4a02ee2a3 100644
--- a/network_client.c
+++ b/network_client.c
@@ -5,6 +5,7 @@
 #include "string.h"
 #include "strings.h"
 #include "network_data.h"
+#include "date.h"
 
 #ifdef ENABLE_NETWORK
 
diff --git a/network_gui.c b/network_gui.c
index 24e42ff12..dd804e6e3 100644
--- a/network_gui.c
+++ b/network_gui.c
@@ -6,6 +6,7 @@
 #include "strings.h"
 #include "table/sprites.h"
 #include "network.h"
+#include "date.h"
 
 #include "fios.h"
 
diff --git a/network_server.c b/network_server.c
index 11b648d8d..aea5f1fde 100644
--- a/network_server.c
+++ b/network_server.c
@@ -6,6 +6,7 @@
 #include "strings.h"
 #include "network_data.h"
 #include "train.h"
+#include "date.h"
 
 #ifdef ENABLE_NETWORK
 
diff --git a/network_udp.c b/network_udp.c
index 1422d9fe4..de811c722 100644
--- a/network_udp.c
+++ b/network_udp.c
@@ -4,6 +4,7 @@
 #include "debug.h"
 #include "string.h"
 #include "network_data.h"
+#include "date.h"
 
 #ifdef ENABLE_NETWORK
 
diff --git a/newgrf_engine.c b/newgrf_engine.c
index cc05de4ea..a2ed35cac 100644
--- a/newgrf_engine.c
+++ b/newgrf_engine.c
@@ -16,6 +16,7 @@
 #include "newgrf_station.h"
 #include "newgrf_spritegroup.h"
 #include "newgrf_cargo.h"
+#include "date.h"
 
 
 
diff --git a/newgrf_spritegroup.c b/newgrf_spritegroup.c
index 0e3225de4..9dd45e6fc 100644
--- a/newgrf_spritegroup.c
+++ b/newgrf_spritegroup.c
@@ -6,6 +6,7 @@
 #include "macros.h"
 #include "pool.h"
 #include "newgrf_spritegroup.h"
+#include "date.h"
 
 enum {
 	SPRITEGROUP_POOL_BLOCK_SIZE_BITS = 4, /* (1 << 4) == 16 items */
diff --git a/newgrf_station.c b/newgrf_station.c
index b3f76648c..0c602f646 100644
--- a/newgrf_station.c
+++ b/newgrf_station.c
@@ -15,6 +15,7 @@
 #include "newgrf_callbacks.h"
 #include "newgrf_station.h"
 #include "newgrf_spritegroup.h"
+#include "date.h"
 
 static StationClass station_classes[STAT_CLASS_MAX];
 
diff --git a/news_gui.c b/news_gui.c
index 4258c3256..d3e4b83f4 100644
--- a/news_gui.c
+++ b/news_gui.c
@@ -14,6 +14,7 @@
 #include "vehicle.h"
 #include "sound.h"
 #include "variables.h"
+#include "date.h"
 
 /* News system
 News system is realized as a FIFO queue (in an array)
diff --git a/oldloader.c b/oldloader.c
index 439801d8d..6f634ac92 100644
--- a/oldloader.c
+++ b/oldloader.c
@@ -18,6 +18,7 @@
 #include "depot.h"
 #include "network.h"
 #include "ai/ai.h"
+#include "date.h"
 
 enum {
 	HEADER_SIZE = 49,
diff --git a/openttd.c b/openttd.c
index 99951ed92..005e2a59d 100644
--- a/openttd.c
+++ b/openttd.c
@@ -48,6 +48,7 @@
 #include "train.h"
 #include "yapf/yapf.h"
 #include "settings.h"
+#include "date.h"
 
 #include <stdarg.h>
 
diff --git a/openttd.h b/openttd.h
index 18fa5b449..b7287dd38 100644
--- a/openttd.h
+++ b/openttd.h
@@ -30,23 +30,6 @@ typedef struct SortStruct {
 	byte		owner;
 } SortStruct;
 
-typedef struct YearMonthDay {
-	int year, month, day;
-} YearMonthDay;
-
-/* --- 1 Day is 74 ticks ---
-* The game's internal structure is dictated by ticks. The date counter (date_fract) is an integer of
-* uint16 type, so it can have a max value of 65536. Every tick this variable (date_fract) is
-* increased by 885. When it overflows, the new day loop is called.
-* * this that means 1 day is : 65536 / 885 = 74 ticks
-* * 1 tick is approximately 27ms.
-* * 1 day is thus about 2 seconds (74*27 = 1998) on a machine that can run OpenTTD normally
-*/
-#define DAY_TICKS 74
-#define MAX_YEAR_BEGIN_REAL 1920
-#define MAX_YEAR_END_REAL 2090
-#define MAX_YEAR_END 170
-
 #include "map.h"
 #include "slope.h"
 
@@ -78,6 +61,9 @@ typedef uint16 UnitID;   ///< All unitnumber stuff is of this type (or anyway, s
 typedef uint32 WindowNumber;
 typedef byte WindowClass;
 
+typedef uint8  Year;
+typedef uint32 Date;
+
 
 enum GameModes {
 	GM_MENU,
diff --git a/openttd.vcproj b/openttd.vcproj
index 107c9a446..a06fd11f7 100644
--- a/openttd.vcproj
+++ b/openttd.vcproj
@@ -184,6 +184,9 @@
 				RelativePath=".\currency.c">
 			</File>
 			<File
+				RelativePath=".\date.c">
+			</File>
+			<File
 				RelativePath=".\debug.c">
 			</File>
 			<File
@@ -431,6 +434,9 @@
 				RelativePath=".\currency.h">
 			</File>
 			<File
+				RelativePath=".\date.h">
+			</File>
+			<File
 				RelativePath=".\debug.h">
 			</File>
 			<File
diff --git a/openttd_vs80.vcproj b/openttd_vs80.vcproj
index f4aa47d35..62f548aab 100644
--- a/openttd_vs80.vcproj
+++ b/openttd_vs80.vcproj
@@ -477,6 +477,10 @@
 				>
 			</File>
 			<File
+				RelativePath=".\date.c"
+				>
+			</File>
+			<File
 				RelativePath=".\debug.c"
 				>
 			</File>
@@ -864,6 +868,10 @@
 				>
 			</File>
 			<File
+				RelativePath=".\date.h"
+				>
+			</File>
+			<File
 				RelativePath=".\debug.h"
 				>
 			</File>
diff --git a/player_gui.c b/player_gui.c
index ed1b46c15..ba978dd53 100644
--- a/player_gui.c
+++ b/player_gui.c
@@ -16,6 +16,7 @@
 #include "network.h"
 #include "variables.h"
 #include "train.h"
+#include "date.h"
 
 #ifdef ENABLE_NETWORK
 #include "network_data.h"
diff --git a/players.c b/players.c
index 9276f9119..9dbf83542 100644
--- a/players.c
+++ b/players.c
@@ -25,6 +25,7 @@
 #include "variables.h"
 #include "engine.h"
 #include "ai/ai.h"
+#include "date.h"
 
 static const SpriteID cheeks_table[4] = {
 	0x325, 0x326,
diff --git a/roadveh_cmd.c b/roadveh_cmd.c
index e36e0ec5f..53cddb281 100644
--- a/roadveh_cmd.c
+++ b/roadveh_cmd.c
@@ -27,6 +27,7 @@
 #include "newgrf_engine.h"
 #include "newgrf_text.h"
 #include "yapf/yapf.h"
+#include "date.h"
 
 static const uint16 _roadveh_images[63] = {
 	0xCD4, 0xCDC, 0xCE4, 0xCEC, 0xCF4, 0xCFC, 0xD0C, 0xD14,
diff --git a/roadveh_gui.c b/roadveh_gui.c
index 18b4a0720..1716c3556 100644
--- a/roadveh_gui.c
+++ b/roadveh_gui.c
@@ -20,6 +20,7 @@
 #include "depot.h"
 #include "vehicle_gui.h"
 #include "newgrf_engine.h"
+#include "date.h"
 
 /**
  * Draw the purchase info details of road vehicle at a given location.
diff --git a/screenshot.c b/screenshot.c
index 8c20fcc92..1acb9d468 100644
--- a/screenshot.c
+++ b/screenshot.c
@@ -12,6 +12,7 @@
 #include "player.h"
 #include "screenshot.h"
 #include "variables.h"
+#include "date.h"
 
 char _screenshot_format_name[8];
 uint _num_screenshot_formats;
diff --git a/settings.c b/settings.c
index 848d8d699..92cdffbea 100644
--- a/settings.c
+++ b/settings.c
@@ -36,6 +36,7 @@
 #include "npf.h"
 #include "yapf/yapf.h"
 #include "newgrf.h"
+#include "date.h"
 
 /** The patch values that are used for new games and/or modified in config file */
 Patches _patches_newgame;
diff --git a/settings_gui.c b/settings_gui.c
index c93833c16..146aa6e18 100644
--- a/settings_gui.c
+++ b/settings_gui.c
@@ -20,6 +20,7 @@
 #include "variables.h"
 #include "settings.h"
 #include "vehicle.h"
+#include "date.h"
 
 static uint32 _difficulty_click_a;
 static uint32 _difficulty_click_b;
diff --git a/ship_cmd.c b/ship_cmd.c
index 7b5737559..ac0492925 100644
--- a/ship_cmd.c
+++ b/ship_cmd.c
@@ -25,6 +25,7 @@
 #include "debug.h"
 #include "newgrf_callbacks.h"
 #include "newgrf_text.h"
+#include "date.h"
 
 static const uint16 _ship_sprites[] = {0x0E5D, 0x0E55, 0x0E65, 0x0E6D};
 static const byte _ship_sometracks[4] = {0x19, 0x16, 0x25, 0x2A};
diff --git a/ship_gui.c b/ship_gui.c
index a3b4ac3d3..96e2db62d 100644
--- a/ship_gui.c
+++ b/ship_gui.c
@@ -20,6 +20,7 @@
 #include "depot.h"
 #include "vehicle_gui.h"
 #include "newgrf_engine.h"
+#include "date.h"
 
 /**
  * Draw the purchase info details of a ship at a given location.
diff --git a/station_cmd.c b/station_cmd.c
index 305364df6..64503fb7f 100644
--- a/station_cmd.c
+++ b/station_cmd.c
@@ -32,6 +32,7 @@
 #include "newgrf_callbacks.h"
 #include "newgrf_station.h"
 #include "yapf/yapf.h"
+#include "date.h"
 
 enum {
 	/* Max stations: 64000 (64 * 1000) */
diff --git a/station_gui.c b/station_gui.c
index 9aad2b710..91f9a56f0 100644
--- a/station_gui.c
+++ b/station_gui.c
@@ -16,6 +16,7 @@
 #include "command.h"
 #include "variables.h"
 #include "vehicle_gui.h"
+#include "date.h"
 
 typedef int CDECL StationSortListingTypeFunction(const void*, const void*);
 
diff --git a/strings.c b/strings.c
index a0434e74b..a0d762878 100644
--- a/strings.c
+++ b/strings.c
@@ -19,6 +19,7 @@
 #include "newgrf_text.h"
 #include "table/landscape_const.h"
 #include "music.h"
+#include "date.h"
 
 #ifdef WIN32
 /* for opendir/readdir/closedir */
diff --git a/subsidy_gui.c b/subsidy_gui.c
index 018980fd9..edb6ede75 100644
--- a/subsidy_gui.c
+++ b/subsidy_gui.c
@@ -12,6 +12,7 @@
 #include "gfx.h"
 #include "economy.h"
 #include "variables.h"
+#include "date.h"
 
 static void HandleSubsidyClick(int y)
 {
diff --git a/texteff.c b/texteff.c
index 34c1d4641..74f421612 100644
--- a/texteff.c
+++ b/texteff.c
@@ -13,6 +13,7 @@
 #include "variables.h"
 #include "table/sprites.h"
 #include <stdarg.h> /* va_list */
+#include "date.h"
 
 typedef struct TextEffect {
 	StringID string_id;
diff --git a/town_cmd.c b/town_cmd.c
index f87f1917c..e0c3c41d4 100644
--- a/town_cmd.c
+++ b/town_cmd.c
@@ -26,6 +26,7 @@
 #include "water_map.h"
 #include "variables.h"
 #include "bridge.h"
+#include "date.h"
 #include "table/town_land.h"
 
 enum {
diff --git a/train_cmd.c b/train_cmd.c
index d2a34decc..8d711befb 100644
--- a/train_cmd.c
+++ b/train_cmd.c
@@ -30,6 +30,7 @@
 #include "newgrf_text.h"
 #include "direction.h"
 #include "yapf/yapf.h"
+#include "date.h"
 
 static bool TrainCheckIfLineEnds(Vehicle *v);
 static void TrainController(Vehicle *v);
diff --git a/train_gui.c b/train_gui.c
index 376556071..4b6091702 100644
--- a/train_gui.c
+++ b/train_gui.c
@@ -21,6 +21,7 @@
 #include "depot.h"
 #include "train.h"
 #include "newgrf_engine.h"
+#include "date.h"
 
 /**
  * Draw the purchase info details of train engine at a given location.
diff --git a/tunnelbridge_cmd.c b/tunnelbridge_cmd.c
index ebb5a2083..00c8f33a1 100644
--- a/tunnelbridge_cmd.c
+++ b/tunnelbridge_cmd.c
@@ -27,6 +27,7 @@
 #include "train.h"
 #include "water_map.h"
 #include "yapf/yapf.h"
+#include "date.h"
 
 #include "table/bridge_land.h"
 
diff --git a/variables.h b/variables.h
index b47108f36..f0c06d6a1 100644
--- a/variables.h
+++ b/variables.h
@@ -39,10 +39,6 @@ VARDEF GameOptions _opt_newgame;
 // Pointer to one of the two _opt OR _opt_newgame structs
 VARDEF GameOptions *_opt_ptr;
 
-// Current date
-VARDEF uint16 _date;
-VARDEF uint16 _date_fract;
-
 // Amount of game ticks
 VARDEF uint16 _tick_counter;
 
@@ -257,10 +253,6 @@ VARDEF Paths _path;
 VARDEF int _timer_counter;
 
 
-// NOSAVE: can be determined from _date
-VARDEF byte _cur_year;
-VARDEF byte _cur_month;
-
 VARDEF uint32 _frame_counter;
 
 VARDEF bool _is_old_ai_player; // current player is an oldAI player? (enables a lot of cheats..)
diff --git a/vehicle.c b/vehicle.c
index c2628e0d2..9dcdc29be 100644
--- a/vehicle.c
+++ b/vehicle.c
@@ -31,6 +31,7 @@
 #include "water_map.h"
 #include "network.h"
 #include "yapf/yapf.h"
+#include "date.h"
 
 #define INVALID_COORD (-0x8000)
 #define GEN_HASH(x, y) ((GB((y), 6, 6) << 6) + GB((x), 7, 6))
diff --git a/vehicle_gui.c b/vehicle_gui.c
index 743b4e810..8b24a5653 100644
--- a/vehicle_gui.c
+++ b/vehicle_gui.c
@@ -22,6 +22,7 @@
 #include "newgrf_callbacks.h"
 #include "newgrf_engine.h"
 #include "newgrf_text.h"
+#include "date.h"
 
 Sorting _sorting;
 
diff --git a/waypoint.c b/waypoint.c
index 9a44b6e9f..4d0b9a519 100644
--- a/waypoint.c
+++ b/waypoint.c
@@ -18,6 +18,7 @@
 #include "table/strings.h"
 #include "vehicle.h"
 #include "yapf/yapf.h"
+#include "date.h"
 
 enum {
 	/* Max waypoints: 64000 (8 * 8000) */
diff --git a/yapf/yapf.hpp b/yapf/yapf.hpp
index 50ae497ad..a35140be8 100644
--- a/yapf/yapf.hpp
+++ b/yapf/yapf.hpp
@@ -16,7 +16,7 @@ EXTERN_C_BEGIN
 #include "../station.h"
 #include "../station_map.h"
 #include "../vehicle.h"
-#include "../variables.h"
+#include "../date.h"
 #include "../functions.h"
 #include "yapf.h"
 #include "../pathfind.h"