openttd.c
author KUDr
Sun, 31 Dec 2006 02:53:23 +0000
branchcustombridgeheads
changeset 5611 11da6bafbfb9
parent 5598 166345600ba9
child 5623 ef2a8a524a95
permissions -rw-r--r--
(svn r7687) [cbh] - Fix: trains can now enter the bridge from side. They still can't leave it from side (pathfinder will need to be invoked when the other ramp is entered). Also the code is not very clear and needs review. It is more proof of concept than final solution. I hope that somebody smarter (Celestar) can do it better.
/* $Id$ */

#include "stdafx.h"
#include "string.h"
#include "table/strings.h"
#include "debug.h"
#include "driver.h"
#include "saveload.h"
#include "strings.h"
#include "map.h"
#include "tile.h"
#include "void_map.h"

#define VARDEF
#include "openttd.h"
#include "bridge_map.h"
#include "functions.h"
#include "mixer.h"
#include "spritecache.h"
#include "strings.h"
#include "gfx.h"
#include "gfxinit.h"
#include "gui.h"
#include "station.h"
#include "station_map.h"
#include "town_map.h"
#include "tunnel_map.h"
#include "vehicle.h"
#include "viewport.h"
#include "window.h"
#include "player.h"
#include "command.h"
#include "town.h"
#include "industry.h"
#include "news.h"
#include "engine.h"
#include "sound.h"
#include "economy.h"
#include "fileio.h"
#include "hal.h"
#include "airport.h"
#include "console.h"
#include "screenshot.h"
#include "network.h"
#include "signs.h"
#include "depot.h"
#include "waypoint.h"
#include "ai/ai.h"
#include "train.h"
#include "yapf/yapf.h"
#include "settings.h"
#include "genworld.h"
#include "date.h"
#include "clear_map.h"
#include "fontcache.h"
#include "newgrf_config.h"

#include "bridge_map.h"
#include "clear_map.h"
#include "rail_map.h"
#include "road_map.h"
#include "water_map.h"

#include <stdarg.h>

void CallLandscapeTick(void);
void IncreaseDate(void);
void DoPaletteAnimations(void);
void MusicLoop(void);
void ResetMusic(void);
void InitializeStations(void);
void DeleteAllPlayerStations(void);

extern void SetDifficultyLevel(int mode, GameOptions *gm_opt);
extern void DoStartupNewPlayer(bool is_ai);
extern void ShowOSErrorBox(const char *buf);

/* TODO: usrerror() for errors which are not of an internal nature but
 * caused by the user, i.e. missing files or fatal configuration errors.
 * Post-0.4.0 since Celestar doesn't want this in SVN before. --pasky */

void CDECL error(const char *s, ...)
{
	va_list va;
	char buf[512];

	va_start(va, s);
	vsnprintf(buf, lengthof(buf), s, va);
	va_end(va);

	ShowOSErrorBox(buf);
	if (_video_driver != NULL) _video_driver->stop();

	assert(0);
	exit(1);
}

void CDECL ShowInfoF(const char *str, ...)
{
	va_list va;
	char buf[1024];
	va_start(va, str);
	vsnprintf(buf, lengthof(buf), str, va);
	va_end(va);
	ShowInfo(buf);
}


void *ReadFileToMem(const char *filename, size_t *lenp, size_t maxsize)
{
	FILE *in;
	byte *mem;
	size_t len;

	in = fopen(filename, "rb");
	if (in == NULL) return NULL;

	fseek(in, 0, SEEK_END);
	len = ftell(in);
	fseek(in, 0, SEEK_SET);
	if (len > maxsize || (mem = malloc(len + 1)) == NULL) {
		fclose(in);
		return NULL;
	}
	mem[len] = 0;
	if (fread(mem, len, 1, in) != 1) {
		fclose(in);
		free(mem);
		return NULL;
	}
	fclose(in);

	*lenp = len;
	return mem;
}

static void showhelp(void)
{
	extern const char _openttd_revision[];
	char buf[4096], *p;

	p = buf;

	p += snprintf(p, lengthof(buf), "OpenTTD %s\n", _openttd_revision);
	p = strecpy(p,
		"\n"
		"\n"
		"Command line options:\n"
		"  -v drv              = Set video driver (see below)\n"
		"  -s drv              = Set sound driver (see below)\n"
		"  -m drv              = Set music driver (see below)\n"
		"  -r res              = Set resolution (for instance 800x600)\n"
		"  -h                  = Display this help text\n"
		"  -t year             = Set starting year\n"
		"  -d [[fac=]lvl[,...]]= Debug mode\n"
		"  -e                  = Start Editor\n"
		"  -g [savegame]       = Start new/save game immediately\n"
		"  -G seed             = Set random seed\n"
		"  -n [ip#player:port] = Start networkgame\n"
		"  -D                  = Start dedicated server\n"
#if !defined(__MORPHOS__) && !defined(__AMIGA__) && !defined(WIN32)
		"  -f                  = Fork into the background (dedicated only)\n"
#endif
		"  -i                  = Force to use the DOS palette\n"
		"                          (use this if you see a lot of pink)\n"
		"  -c config_file      = Use 'config_file' instead of 'openttd.cfg'\n"
		"\n",
		lastof(buf)
	);

	p = GetDriverList(p, lastof(buf));

	ShowInfo(buf);
}


typedef struct {
	char *opt;
	int numleft;
	char **argv;
	const char *options;
	char *cont;
} MyGetOptData;

static void MyGetOptInit(MyGetOptData *md, int argc, char **argv, const char *options)
{
	md->cont = NULL;
	md->numleft = argc;
	md->argv = argv;
	md->options = options;
}

static int MyGetOpt(MyGetOptData *md)
{
	char *s,*r,*t;

	s = md->cont;
	if (s != NULL)
		goto md_continue_here;

	for (;;) {
		if (--md->numleft < 0) return -1;

		s = *md->argv++;
		if (*s == '-') {
md_continue_here:;
			s++;
			if (*s != 0) {
				// Found argument, try to locate it in options.
				if (*s == ':' || (r = strchr(md->options, *s)) == NULL) {
					// ERROR!
					return -2;
				}
				if (r[1] == ':') {
					// Item wants an argument. Check if the argument follows, or if it comes as a separate arg.
					if (!*(t = s + 1)) {
						// It comes as a separate arg. Check if out of args?
						if (--md->numleft < 0 || *(t = *md->argv) == '-') {
							// Check if item is optional?
							if (r[2] != ':')
								return -2;
							md->numleft++;
							t = NULL;
						} else {
							md->argv++;
						}
					}
					md->opt = t;
					md->cont = NULL;
					return *s;
				}
				md->opt = NULL;
				md->cont = s;
				return *s;
			}
		} else {
			// This is currently not supported.
			return -2;
		}
	}
}


static void ParseResolution(int res[2], const char *s)
{
	char *t = strchr(s, 'x');
	if (t == NULL) {
		ShowInfoF("Invalid resolution '%s'", s);
		return;
	}

	res[0] = clamp(strtoul(s, NULL, 0), 64, MAX_SCREEN_WIDTH);
	res[1] = clamp(strtoul(t + 1, NULL, 0), 64, MAX_SCREEN_HEIGHT);
}

static void InitializeDynamicVariables(void)
{
	/* Dynamic stuff needs to be initialized somewhere... */
	_town_sort     = NULL;
	_industry_sort = NULL;
}

static void UnInitializeDynamicVariables(void)
{
	/* Dynamic stuff needs to be free'd somewhere... */
	CleanPool(&_Town_pool);
	CleanPool(&_Industry_pool);
	CleanPool(&_Station_pool);
	CleanPool(&_Vehicle_pool);
	CleanPool(&_Sign_pool);
	CleanPool(&_Order_pool);

	free((void*)_town_sort);
	free((void*)_industry_sort);
}

static void UnInitializeGame(void)
{
	UnInitWindowSystem();

	free(_config_file);
}

static void LoadIntroGame(void)
{
	char filename[256];

	_game_mode = GM_MENU;
	CLRBITS(_display_opt, DO_TRANS_BUILDINGS); // don't make buildings transparent in intro
	_opt_ptr = &_opt_newgame;
	ResetGRFConfig(false);

	// Setup main window
	ResetWindowSystem();
	SetupColorsAndInitialWindow();

	// Generate a world.
	snprintf(filename, lengthof(filename), "%sopntitle.dat",  _paths.data_dir);
#if defined SECOND_DATA_DIR
	if (SaveOrLoad(filename, SL_LOAD) != SL_OK) {
		snprintf(filename, lengthof(filename), "%sopntitle.dat",  _paths.second_data_dir);
	}
#endif
	if (SaveOrLoad(filename, SL_LOAD) != SL_OK) {
		GenerateWorld(GW_EMPTY, 64, 64); // if failed loading, make empty world.
		WaitTillGeneratedWorld();
	}

	_pause = 0;
	SetLocalPlayer(0);
	/* Make sure you can't scroll in the menu */
	_scrolling_viewport = 0;
	_cursor.fix_at = false;
	MarkWholeScreenDirty();

	// Play main theme
	if (_music_driver->is_song_playing()) ResetMusic();
}

#if defined(UNIX) && !defined(__MORPHOS__)
extern void DedicatedFork(void);
#endif

int ttd_main(int argc, char *argv[])
{
	MyGetOptData mgo;
	int i;
	const char *optformat;
	char musicdriver[16], sounddriver[16], videodriver[16];
	int resolution[2] = {0,0};
	Year startyear = INVALID_YEAR;
	uint generation_seed = GENERATE_NEW_SEED;
	bool dedicated = false;
	bool network   = false;
	char *network_conn = NULL;

	musicdriver[0] = sounddriver[0] = videodriver[0] = 0;

	_game_mode = GM_MENU;
	_switch_mode = SM_MENU;
	_switch_mode_errorstr = INVALID_STRING_ID;
	_dedicated_forks = false;
	_config_file = NULL;

	// The last param of the following function means this:
	//   a letter means: it accepts that param (e.g.: -h)
	//   a ':' behind it means: it need a param (e.g.: -m<driver>)
	//   a '::' behind it means: it can optional have a param (e.g.: -d<debug>)
	optformat = "m:s:v:hDn::eit:d::r:g::G:c:"
#if !defined(__MORPHOS__) && !defined(__AMIGA__) && !defined(WIN32)
		"f"
#endif
	;

	MyGetOptInit(&mgo, argc-1, argv+1, optformat);
	while ((i = MyGetOpt(&mgo)) != -1) {
		switch (i) {
		case 'm': ttd_strlcpy(musicdriver, mgo.opt, sizeof(musicdriver)); break;
		case 's': ttd_strlcpy(sounddriver, mgo.opt, sizeof(sounddriver)); break;
		case 'v': ttd_strlcpy(videodriver, mgo.opt, sizeof(videodriver)); break;
		case 'D':
			strcpy(musicdriver, "null");
			strcpy(sounddriver, "null");
			strcpy(videodriver, "dedicated");
			dedicated = true;
			break;
		case 'f': _dedicated_forks = true; break;
		case 'n':
			network = true;
			network_conn = mgo.opt; // optional IP parameter, NULL if unset
			break;
		case 'r': ParseResolution(resolution, mgo.opt); break;
		case 't': startyear = atoi(mgo.opt); break;
		case 'd': {
#if defined(WIN32)
				CreateConsole();
#endif
				if (mgo.opt != NULL) SetDebugString(mgo.opt);
			} break;
		case 'e': _switch_mode = SM_EDITOR; break;
		case 'i': _use_dos_palette = true; break;
		case 'g':
			if (mgo.opt != NULL) {
				strcpy(_file_to_saveload.name, mgo.opt);
				_switch_mode = SM_LOAD;
			} else {
				_switch_mode = SM_NEWGAME;
			}
			break;
		case 'G': generation_seed = atoi(mgo.opt); break;
		case 'c': _config_file = strdup(mgo.opt); break;
		case -2:
		case 'h':
			showhelp();
			return 0;
		}
	}

	DeterminePaths();
	CheckExternalFiles();

#if defined(UNIX) && !defined(__MORPHOS__)
	// We must fork here, or we'll end up without some resources we need (like sockets)
	if (_dedicated_forks)
		DedicatedFork();
#endif

	LoadFromConfig();
	CheckConfig();
	LoadFromHighScore();

	// override config?
	if (musicdriver[0]) ttd_strlcpy(_ini_musicdriver, musicdriver, sizeof(_ini_musicdriver));
	if (sounddriver[0]) ttd_strlcpy(_ini_sounddriver, sounddriver, sizeof(_ini_sounddriver));
	if (videodriver[0]) ttd_strlcpy(_ini_videodriver, videodriver, sizeof(_ini_videodriver));
	if (resolution[0]) { _cur_resolution[0] = resolution[0]; _cur_resolution[1] = resolution[1]; }
	if (startyear != INVALID_YEAR) _patches_newgame.starting_year = startyear;
	if (generation_seed != GENERATE_NEW_SEED) _patches_newgame.generation_seed = generation_seed;

	if (_dedicated_forks && !dedicated) _dedicated_forks = false;

	// enumerate language files
	InitializeLanguagePacks();

	// initialize screenshot formats
	InitializeScreenshotFormats();

	// initialize airport state machines
	InitializeAirports();

	/* initialize all variables that are allocated dynamically */
	InitializeDynamicVariables();

	/* start the AI */
	AI_Initialize();

	// Sample catalogue
	DEBUG(misc, 1, "Loading sound effects...");
	MxInitialize(11025);
	SoundInitialize("sample.cat");

	/* Initialize FreeType */
	InitFreeType();

	// This must be done early, since functions use the InvalidateWindow* calls
	InitWindowSystem();

	/* Initialize game palette */
	GfxInitPalettes();

	DEBUG(driver, 1, "Loading drivers...");
	LoadDriver(SOUND_DRIVER, _ini_sounddriver);
	LoadDriver(MUSIC_DRIVER, _ini_musicdriver);
	LoadDriver(VIDEO_DRIVER, _ini_videodriver); // load video last, to prevent an empty window while sound and music loads
	_savegame_sort_order = SORT_BY_DATE | SORT_DESCENDING;

	// restore saved music volume
	_music_driver->set_volume(msf.music_vol);

	NetworkStartUp(); // initialize network-core

	ScanNewGRFFiles();

	_opt_ptr = &_opt_newgame;
	ResetGRFConfig(false);

	/* XXX - ugly hack, if diff_level is 9, it means we got no setting from the config file */
	if (_opt_newgame.diff_level == 9) SetDifficultyLevel(0, &_opt_newgame);

	/* Make sure _patches is filled with _patches_newgame if we switch to a game directly */
	if (_switch_mode != SM_NONE) {
		_opt = _opt_newgame;
		UpdatePatches();
	}

	// initialize the ingame console
	IConsoleInit();
	_cursor.in_window = true;
	InitializeGUI();
	IConsoleCmdExec("exec scripts/autoexec.scr 0");

	GenerateWorld(GW_EMPTY, 64, 64); // Make the viewport initialization happy
	WaitTillGeneratedWorld();

#ifdef ENABLE_NETWORK
	if (network && _network_available) {
		if (network_conn != NULL) {
			const char *port = NULL;
			const char *player = NULL;
			uint16 rport;

			rport = NETWORK_DEFAULT_PORT;
			_network_playas = PLAYER_NEW_COMPANY;

			ParseConnectionString(&player, &port, network_conn);

			if (player != NULL) {
				_network_playas = atoi(player);

				if (_network_playas != PLAYER_SPECTATOR) {
					_network_playas--;
					if (!IsValidPlayer(_network_playas)) return false;
				}
			}
			if (port != NULL) rport = atoi(port);

			LoadIntroGame();
			_switch_mode = SM_NONE;
			NetworkClientConnectGame(network_conn, rport);
		}
	}
#endif /* ENABLE_NETWORK */

	_video_driver->main_loop();

	WaitTillSaved();
	IConsoleFree();

	if (_network_available) NetworkShutDown(); // Shut down the network and close any open connections

	_video_driver->stop();
	_music_driver->stop();
	_sound_driver->stop();

	SaveToConfig();
	SaveToHighScore();

	// uninitialize airport state machines
	UnInitializeAirports();

	/* uninitialize variables that are allocated dynamic */
	UnInitializeDynamicVariables();

	/* stop the AI */
	AI_Uninitialize();

	/* Close all and any open filehandles */
	FioCloseAll();
	UnInitializeGame();

	return 0;
}

void HandleExitGameRequest(void)
{
	if (_game_mode == GM_MENU) { // do not ask to quit on the main screen
		_exit_game = true;
	} else if (_patches.autosave_on_exit) {
		DoExitSave();
		_exit_game = true;
	} else {
		AskExitGame();
	}
}


/** Mutex so that only one thread can communicate with the main program
 * at any given time */
static ThreadMsg _message = MSG_OTTD_NO_MESSAGE;

static inline void OTTD_ReleaseMutex(void) {_message = MSG_OTTD_NO_MESSAGE;}
static inline ThreadMsg OTTD_PollThreadEvent(void) {return _message;}

/** Called by running thread to execute some action in the main game.
 * It will stall as long as the mutex is not freed (handled) by the game */
void OTTD_SendThreadMessage(ThreadMsg msg)
{
	if (_exit_game) return;
	while (_message != MSG_OTTD_NO_MESSAGE) CSleep(10);

	_message = msg;
}


/** Handle the user-messages sent to us
 * @param message message sent
 */
static void ProcessSentMessage(ThreadMsg message)
{
	switch (message) {
		case MSG_OTTD_SAVETHREAD_DONE:  SaveFileDone(); break;
		case MSG_OTTD_SAVETHREAD_ERROR: SaveFileError(); break;
		default: NOT_REACHED();
	}

	OTTD_ReleaseMutex(); // release mutex so that other threads, messages can be handled
}

static void ShowScreenshotResult(bool b)
{
	if (b) {
		SetDParamStr(0, _screenshot_name);
		ShowErrorMessage(INVALID_STRING_ID, STR_031B_SCREENSHOT_SUCCESSFULLY, 0, 0);
	} else {
		ShowErrorMessage(INVALID_STRING_ID, STR_031C_SCREENSHOT_FAILED, 0, 0);
	}

}

static void MakeNewGameDone(void)
{
	/* In a dedicated server, the server does not play */
	if (_network_dedicated) {
		SetLocalPlayer(PLAYER_SPECTATOR);
		return;
	}

	/* Create a single player */
	DoStartupNewPlayer(false);

	SetLocalPlayer(0);
	_current_player = _local_player;
	DoCommandP(0, (_patches.autorenew << 15 ) | (_patches.autorenew_months << 16) | 4, _patches.autorenew_money, NULL, CMD_SET_AUTOREPLACE);

	SettingsDisableElrail(_patches.disable_elrails);

	MarkWholeScreenDirty();
}

static void MakeNewGame(bool from_heightmap)
{
	_game_mode = GM_NORMAL;

	ResetGRFConfig(true);

	GenerateWorldSetCallback(&MakeNewGameDone);
	GenerateWorld(from_heightmap ? GW_HEIGHTMAP : GW_NEWGAME, 1 << _patches.map_x, 1 << _patches.map_y);
}

static void MakeNewEditorWorldDone(void)
{
	SetLocalPlayer(OWNER_NONE);

	MarkWholeScreenDirty();
}

static void MakeNewEditorWorld(void)
{
	_game_mode = GM_EDITOR;

	ResetGRFConfig(true);

	GenerateWorldSetCallback(&MakeNewEditorWorldDone);
	GenerateWorld(GW_EMPTY, 1 << _patches.map_x, 1 << _patches.map_y);
}

void StartupPlayers(void);
void StartupDisasters(void);
extern void StartupEconomy(void);

/**
 * Start Scenario starts a new game based on a scenario.
 * Eg 'New Game' --> select a preset scenario
 * This starts a scenario based on your current difficulty settings
 */
static void StartScenario(void)
{
	_game_mode = GM_NORMAL;

	// invalid type
	if (_file_to_saveload.mode == SL_INVALID) {
		DEBUG(sl, 0, "Savegame is obsolete or invalid format: '%s'", _file_to_saveload.name);
		ShowErrorMessage(INVALID_STRING_ID, STR_4009_GAME_LOAD_FAILED, 0, 0);
		_game_mode = GM_MENU;
		return;
	}

	// Reinitialize windows
	ResetWindowSystem();

	SetupColorsAndInitialWindow();

	ResetGRFConfig(true);

	// Load game
	if (SaveOrLoad(_file_to_saveload.name, _file_to_saveload.mode) != SL_OK) {
		LoadIntroGame();
		ShowErrorMessage(INVALID_STRING_ID, STR_4009_GAME_LOAD_FAILED, 0, 0);
	}

	_opt_ptr = &_opt;
	_opt_ptr->diff = _opt_newgame.diff;
	_opt.diff_level = _opt_newgame.diff_level;

	// Inititalize data
	StartupEconomy();
	StartupPlayers();
	StartupEngines();
	StartupDisasters();

	SetLocalPlayer(0);
	_current_player = _local_player;
	DoCommandP(0, (_patches.autorenew << 15 ) | (_patches.autorenew_months << 16) | 4, _patches.autorenew_money, NULL, CMD_SET_AUTOREPLACE);

	MarkWholeScreenDirty();
}

bool SafeSaveOrLoad(const char *filename, int mode, int newgm)
{
	byte ogm = _game_mode;

	_game_mode = newgm;
	switch (SaveOrLoad(filename, mode)) {
		case SL_OK: return true;

		case SL_REINIT:
			switch (ogm) {
				case GM_MENU:   LoadIntroGame();      break;
				case GM_EDITOR: MakeNewEditorWorld(); break;
				default:        MakeNewGame(false);   break;
			}
			return false;

		default:
			_game_mode = ogm;
			return false;
	}
}

void SwitchMode(int new_mode)
{
#ifdef ENABLE_NETWORK
	// If we are saving something, the network stays in his current state
	if (new_mode != SM_SAVE) {
		// If the network is active, make it not-active
		if (_networking) {
			if (_network_server && (new_mode == SM_LOAD || new_mode == SM_NEWGAME)) {
				NetworkReboot();
				NetworkUDPClose();
			} else {
				NetworkDisconnect();
				NetworkUDPClose();
			}
		}

		// If we are a server, we restart the server
		if (_is_network_server) {
			// But not if we are going to the menu
			if (new_mode != SM_MENU) {
				NetworkServerStart();
			} else {
				// This client no longer wants to be a network-server
				_is_network_server = false;
			}
		}
	}
#endif /* ENABLE_NETWORK */

	switch (new_mode) {
	case SM_EDITOR: /* Switch to scenario editor */
		MakeNewEditorWorld();
		break;

	case SM_NEWGAME: /* New Game --> 'Random game' */
#ifdef ENABLE_NETWORK
		if (_network_server) {
			snprintf(_network_game_info.map_name, lengthof(_network_game_info.map_name), "Random Map");
		}
#endif /* ENABLE_NETWORK */
		MakeNewGame(false);
		break;

	case SM_START_SCENARIO: /* New Game --> Choose one of the preset scenarios */
#ifdef ENABLE_NETWORK
		if (_network_server) {
			snprintf(_network_game_info.map_name, lengthof(_network_game_info.map_name), "%s (Loaded scenario)", _file_to_saveload.title);
		}
#endif /* ENABLE_NETWORK */
		StartScenario();
		break;

	case SM_LOAD: { /* Load game, Play Scenario */
		_opt_ptr = &_opt;
		ResetGRFConfig(true);

		if (!SafeSaveOrLoad(_file_to_saveload.name, _file_to_saveload.mode, GM_NORMAL)) {
			LoadIntroGame();
			ShowErrorMessage(INVALID_STRING_ID, STR_4009_GAME_LOAD_FAILED, 0, 0);
		} else {
			/* Update the local player for a loaded game. It is either always
			 * player #1 (eg 0) or in the case of a dedicated server a spectator */
			SetLocalPlayer(_network_dedicated ? PLAYER_SPECTATOR : 0);
			DoCommandP(0, 0, 0, NULL, CMD_PAUSE); // decrease pause counter (was increased from opening load dialog)
#ifdef ENABLE_NETWORK
			if (_network_server) {
				snprintf(_network_game_info.map_name, lengthof(_network_game_info.map_name), "%s (Loaded game)", _file_to_saveload.title);
			}
#endif /* ENABLE_NETWORK */
		}
		break;
	}

	case SM_START_HEIGHTMAP: /* Load a heightmap and start a new game from it */
#ifdef ENABLE_NETWORK
		if (_network_server) {
			snprintf(_network_game_info.map_name, lengthof(_network_game_info.map_name), "%s (Heightmap)", _file_to_saveload.title);
		}
#endif /* ENABLE_NETWORK */
		MakeNewGame(true);
		break;

	case SM_LOAD_HEIGHTMAP: /* Load heightmap from scenario editor */
		SetLocalPlayer(OWNER_NONE);

		GenerateWorld(GW_HEIGHTMAP, 1 << _patches.map_x, 1 << _patches.map_y);
		MarkWholeScreenDirty();
		break;

	case SM_LOAD_SCENARIO: { /* Load scenario from scenario editor */
		if (SafeSaveOrLoad(_file_to_saveload.name, _file_to_saveload.mode, GM_EDITOR)) {
			Player *p;

			_opt_ptr = &_opt;

			SetLocalPlayer(OWNER_NONE);
			_generating_world = true;
			/* Delete all players */
			FOR_ALL_PLAYERS(p) {
				if (p->is_active) {
					ChangeOwnershipOfPlayerItems(p->index, PLAYER_SPECTATOR);
					p->is_active = false;
				}
			}
			_generating_world = false;
			_patches_newgame.starting_year = _cur_year;
			// delete all stations owned by a player
			DeleteAllPlayerStations();
		} else {
			ShowErrorMessage(INVALID_STRING_ID, STR_4009_GAME_LOAD_FAILED, 0, 0);
		}
		break;
	}

	case SM_MENU: /* Switch to game intro menu */
		LoadIntroGame();
		break;

	case SM_SAVE: /* Save game */
		if (SaveOrLoad(_file_to_saveload.name, SL_SAVE) != SL_OK) {
			ShowErrorMessage(INVALID_STRING_ID, STR_4007_GAME_SAVE_FAILED, 0, 0);
		} else {
			DeleteWindowById(WC_SAVELOAD, 0);
		}
		break;

	case SM_GENRANDLAND: /* Generate random land within scenario editor */
		SetLocalPlayer(OWNER_NONE);
		GenerateWorld(GW_RANDOM, 1 << _patches.map_x, 1 << _patches.map_y);
		// XXX: set date
		MarkWholeScreenDirty();
		break;
	}

	if (_switch_mode_errorstr != INVALID_STRING_ID) {
		ShowErrorMessage(INVALID_STRING_ID, _switch_mode_errorstr, 0, 0);
	}
}


// State controlling game loop.
// The state must not be changed from anywhere
// but here.
// That check is enforced in DoCommand.
void StateGameLoop(void)
{
	// dont execute the state loop during pause
	if (_pause) return;
	if (IsGeneratingWorld()) return;

	if (_game_mode == GM_EDITOR) {
		RunTileLoop();
		CallVehicleTicks();
		CallLandscapeTick();
		CallWindowTickEvent();
		NewsLoop();
	} else {
		// All these actions has to be done from OWNER_NONE
		//  for multiplayer compatibility
		PlayerID p = _current_player;
		_current_player = OWNER_NONE;

		AnimateAnimatedTiles();
		IncreaseDate();
		RunTileLoop();
		CallVehicleTicks();
		CallLandscapeTick();

		AI_RunGameLoop();

		CallWindowTickEvent();
		NewsLoop();
		_current_player = p;
	}
}

static void DoAutosave(void)
{
	char buf[200];

	if (_patches.keep_all_autosave && _local_player != PLAYER_SPECTATOR) {
		const Player *p = GetPlayer(_local_player);
		char* s = buf;

		s += snprintf(buf, lengthof(buf), "%s%s", _paths.autosave_dir, PATHSEP);

		SetDParam(0, p->name_1);
		SetDParam(1, p->name_2);
		SetDParam(2, _date);
		s = GetString(s, STR_4004, lastof(buf));
		strecpy(s, ".sav", lastof(buf));
	} else { /* generate a savegame name and number according to _patches.max_num_autosaves */
		snprintf(buf, lengthof(buf), "%s%sautosave%d.sav", _paths.autosave_dir, PATHSEP, _autosave_ctr);

		_autosave_ctr++;
		if (_autosave_ctr >= _patches.max_num_autosaves) {
			// we reached the limit for numbers of autosaves. We will start over
			_autosave_ctr = 0;
		}
	}

	DEBUG(sl, 2, "Autosaving to '%s'", buf);
	if (SaveOrLoad(buf, SL_SAVE) != SL_OK)
		ShowErrorMessage(INVALID_STRING_ID, STR_AUTOSAVE_FAILED, 0, 0);
}

static void ScrollMainViewport(int x, int y)
{
	if (_game_mode != GM_MENU) {
		Window *w = FindWindowById(WC_MAIN_WINDOW, 0);
		assert(w);

		WP(w,vp_d).scrollpos_x += x << w->viewport->zoom;
		WP(w,vp_d).scrollpos_y += y << w->viewport->zoom;
	}
}

static const int8 scrollamt[16][2] = {
	{ 0,  0},
	{-2,  0}, //  1 : left
	{ 0, -2}, //  2 : up
	{-2, -1}, //  3 : left + up
	{ 2,  0}, //  4 : right
	{ 0,  0}, //  5 : left + right
	{ 2, -1}, //  6 : right + up
	{ 0, -2}, //  7 : left + right + up = up
	{ 0  ,2}, //  8 : down
	{-2  ,1}, //  9 : down+left
	{ 0,  0}, // 10 : impossible
	{-2,  0}, // 11 : left + up + down = left
	{ 2,  1}, // 12 : down+right
	{ 0,  2}, // 13 : left + right + down = down
	{ 0, -2}, // 14 : left + right + up = up
	{ 0,  0}, // 15 : impossible
};

static void HandleKeyScrolling(void)
{
	if (_dirkeys && !_no_scroll) {
		int factor = _shift_pressed ? 50 : 10;
		ScrollMainViewport(scrollamt[_dirkeys][0] * factor, scrollamt[_dirkeys][1] * factor);
	}
}

void GameLoop(void)
{
	ThreadMsg message;

	if ((message = OTTD_PollThreadEvent()) != 0) ProcessSentMessage(message);

	// autosave game?
	if (_do_autosave) {
		_do_autosave = false;
		DoAutosave();
		RedrawAutosave();
	}

	// handle scrolling of the main window
	HandleKeyScrolling();

	// make a screenshot?
	if (IsScreenshotRequested()) ShowScreenshotResult(MakeScreenshot());

	// switch game mode?
	if (_switch_mode != SM_NONE) {
		SwitchMode(_switch_mode);
		_switch_mode = SM_NONE;
	}

	IncreaseSpriteLRU();
	InteractiveRandom();

	if (_scroller_click_timeout > 3) {
		_scroller_click_timeout -= 3;
	} else {
		_scroller_click_timeout = 0;
	}

	_caret_timer += 3;
	_timer_counter += 8;
	CursorTick();

#ifdef ENABLE_NETWORK
	// Check for UDP stuff
	if (_network_available) NetworkUDPGameLoop();

	if (_networking && !IsGeneratingWorld()) {
		// Multiplayer
		NetworkGameLoop();
	} else {
		if (_network_reconnect > 0 && --_network_reconnect == 0) {
			// This means that we want to reconnect to the last host
			// We do this here, because it means that the network is really closed
			NetworkClientConnectGame(_network_last_host, _network_last_port);
		}
		// Singleplayer
		StateGameLoop();
	}
#else
	StateGameLoop();
#endif /* ENABLE_NETWORK */

	if (!_pause && _display_opt & DO_FULL_ANIMATION) DoPaletteAnimations();

	if (!_pause || _cheats.build_in_pause.value) MoveAllTextEffects();

	InputLoop();

	MusicLoop();
}

void BeforeSaveGame(void)
{
	const Window *w = FindWindowById(WC_MAIN_WINDOW, 0);

	if (w != NULL) {
		_saved_scrollpos_x = WP(w, const vp_d).scrollpos_x;
		_saved_scrollpos_y = WP(w, const vp_d).scrollpos_y;
		_saved_scrollpos_zoom = w->viewport->zoom;
	}
}

static void ConvertTownOwner(void)
{
	TileIndex tile;

	for (tile = 0; tile != MapSize(); tile++) {
		switch (GetTileType(tile)) {
			case MP_STREET:
				if (IsLevelCrossing(tile) && GetCrossingRoadOwner(tile) & 0x80) {
					SetCrossingRoadOwner(tile, OWNER_TOWN);
				}
				/* FALLTHROUGH */

			case MP_TUNNEL: case MP_STREET_BRIDGE:
				if (GetTileOwner(tile) & 0x80) SetTileOwner(tile, OWNER_TOWN);
				break;

			default: break;
		}
	}
}

// before savegame version 4, the name of the company determined if it existed
static void CheckIsPlayerActive(void)
{
	Player *p;

	FOR_ALL_PLAYERS(p) {
		if (p->name_1 != 0) p->is_active = true;
	}
}

// since savegame version 4.1, exclusive transport rights are stored at towns
static void UpdateExclusiveRights(void)
{
	Town *t;

	FOR_ALL_TOWNS(t) {
		t->exclusivity = (byte)-1;
	}

	/* FIXME old exclusive rights status is not being imported (stored in s->blocked_months_obsolete)
	 *   could be implemented this way:
	 * 1.) Go through all stations
	 *     Build an array town_blocked[ town_id ][ player_id ]
	 *     that stores if at least one station in that town is blocked for a player
	 * 2.) Go through that array, if you find a town that is not blocked for
	 *     one player, but for all others, then give him exclusivity.
	 */
}

static const byte convert_currency[] = {
	 0,  1, 12,  8,  3,
	10, 14, 19,  4,  5,
	 9, 11, 13,  6, 17,
	16, 22, 21,  7, 15,
	18,  2, 20, };

// since savegame version 4.2 the currencies are arranged differently
static void UpdateCurrencies(void)
{
	_opt.currency = convert_currency[_opt.currency];
}

/* Up to revision 1413 the invisible tiles at the southern border have not been
 * MP_VOID, even though they should have. This is fixed by this function
 */
static void UpdateVoidTiles(void)
{
	uint i;

	for (i = 0; i < MapMaxY(); ++i) MakeVoid(i * MapSizeX() + MapMaxX());
	for (i = 0; i < MapSizeX(); ++i) MakeVoid(MapSizeX() * MapMaxY() + i);
}

// since savegame version 6.0 each sign has an "owner", signs without owner (from old games are set to 255)
static void UpdateSignOwner(void)
{
	Sign *si;

	FOR_ALL_SIGNS(si) si->owner = OWNER_NONE;
}

extern void UpdateOldAircraft( void );
extern void UpdateOilRig( void );


static inline RailType UpdateRailType(RailType rt, RailType min)
{
	return rt >= min ? (RailType)(rt + 1): rt;
}

bool AfterLoadGame(void)
{
	Window *w;
	ViewPort *vp;
	Player *p;

	// in version 2.1 of the savegame, town owner was unified.
	if (CheckSavegameVersionOldStyle(2, 1)) ConvertTownOwner();

	// from version 4.1 of the savegame, exclusive rights are stored at towns
	if (CheckSavegameVersionOldStyle(4, 1)) UpdateExclusiveRights();

	// from version 4.2 of the savegame, currencies are in a different order
	if (CheckSavegameVersionOldStyle(4, 2)) UpdateCurrencies();

	// 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
	    (4.3) version, so I just check when versions are older, and then
	    walk through the whole map.. */
	if (CheckSavegameVersionOldStyle(4, 3)) {
		TileIndex tile = TileXY(0, 0);
		uint w = MapSizeX();
		uint h = MapSizeY();

		BEGIN_TILE_LOOP(tile_cur, w, h, tile)
			if (IsTileType(tile_cur, MP_WATER) && GetTileOwner(tile_cur) >= MAX_PLAYERS)
				SetTileOwner(tile_cur, OWNER_WATER);
		END_TILE_LOOP(tile_cur, w, h, tile)
	}

	// convert road side to my format.
	if (_opt.road_side) _opt.road_side = 1;

	/* Check all NewGRFs are present */
	if (!IsGoodGRFConfigList()) return false;

	/* Update current year
	 * must be done before loading sprites as some newgrfs check it */
	SetDate(_date);

	// Load the sprites
	GfxLoadSprites();
	LoadStringWidthTable();

	/* Connect front and rear engines of multiheaded trains and converts
	 * subtype to the new format */
	if (CheckSavegameVersionOldStyle(17, 1)) ConvertOldMultiheadToNew();

	/* Connect front and rear engines of multiheaded trains */
	ConnectMultiheadedTrains();

	// reinit the landscape variables (landscape might have changed)
	InitializeLandscapeVariables(true);

	// Update all vehicles
	AfterLoadVehicles();

	// Update all waypoints
	if (CheckSavegameVersion(12)) FixOldWaypoints();

	UpdateAllWaypointSigns();

	// in version 2.2 of the savegame, we have new airports
	if (CheckSavegameVersionOldStyle(2, 2)) UpdateOldAircraft();

	UpdateAllStationVirtCoord();

	// Setup town coords
	AfterLoadTown();
	UpdateAllSignVirtCoords();

	// make sure there is a town in the game
	if (_game_mode == GM_NORMAL && !ClosestTownFromTile(0, (uint)-1)) {
		_error_message = STR_NO_TOWN_IN_SCENARIO;
		return false;
	}

	// Initialize windows
	ResetWindowSystem();
	SetupColorsAndInitialWindow();

	w = FindWindowById(WC_MAIN_WINDOW, 0);

	WP(w,vp_d).scrollpos_x = _saved_scrollpos_x;
	WP(w,vp_d).scrollpos_y = _saved_scrollpos_y;

	vp = w->viewport;
	vp->zoom = _saved_scrollpos_zoom;
	vp->virtual_width = vp->width << vp->zoom;
	vp->virtual_height = vp->height << vp->zoom;

	// in version 4.1 of the savegame, is_active was introduced to determine
	// if a player does exist, rather then checking name_1
	if (CheckSavegameVersionOldStyle(4, 1)) CheckIsPlayerActive();

	// 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.
	// 1 exeption: network-games. Those can have 0 players
	//   But this exeption is not true for network_servers!
	if (!_players[0].is_active && (!_networking || (_networking && _network_server)))
		DoStartupNewPlayer(false);

	DoZoomInOutWindow(ZOOM_NONE, w); // update button status
	MarkWholeScreenDirty();

	// In 5.1, Oilrigs have been moved (again)
	if (CheckSavegameVersionOldStyle(5, 1)) UpdateOilRig();

	/* 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) {
			switch (GetTileType(tile)) {
				case MP_HOUSE:
					_m[tile].m4 = _m[tile].m2;
					SetTownIndex(tile, CalcClosestTownFromTile(tile, (uint)-1)->index);
					break;

				case MP_STREET:
					_m[tile].m4 |= (_m[tile].m2 << 4);
					if (IsTileOwner(tile, OWNER_TOWN)) {
						SetTownIndex(tile, CalcClosestTownFromTile(tile, (uint)-1)->index);
					} else {
						SetTownIndex(tile, 0);
					}
					break;

				default: break;
			}
		} END_TILE_LOOP(tile, MapSizeX(), MapSizeY(), 0);
	}

	/* 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);
	}

	/* 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) {
			p->engine_renew_list   = NULL;
			p->engine_renew        = false;
			p->engine_renew_months = -6;
			p->engine_renew_money  = 100000;
		}

		/* When loading a game, _local_player is not yet set to the correct value.
		 * However, in a dedicated server we are a spectator, so nothing needs to
		 * happen. In case we are not a dedicated server, the local player always
		 * becomes player 0, unless we are in the scenario editor where all the
		 * players are 'invalid'.
		 */
		if (!_network_dedicated && IsValidPlayer(0)) {
			p = GetPlayer(0);
			p->engine_renew        = _patches.autorenew;
			p->engine_renew_months = _patches.autorenew_months;
			p->engine_renew_money  = _patches.autorenew_money;
		}
	}

	if (CheckSavegameVersion(42)) {
		TileIndex map_end = MapSize();
		TileIndex tile;

		for (tile = 0; tile != map_end; tile++) {
			if (MayHaveBridgeAbove(tile)) ClearBridgeMiddle(tile);
			if (IsTileType(tile, MP_TUNNEL) && HASBIT(_m[tile].m5, 7)) {
				if (HASBIT(_m[tile].m5, 6)) { // middle part
					Axis axis = (Axis)GB(_m[tile].m5, 0, 1);

					if (HASBIT(_m[tile].m5, 5)) { // transport route under bridge?
						if (GB(_m[tile].m5, 3, 2) == TRANSPORT_RAIL) {
							MakeRailNormal(
								tile,
								GetTileOwner(tile),
								axis == AXIS_X ? TRACK_BIT_Y : TRACK_BIT_X,
								GetRailType(tile)
							);
						} else {
							TownID town = IsTileOwner(tile, OWNER_TOWN) ? ClosestTownFromTile(tile, (uint)-1)->index : 0;

							MakeRoadNormal(
								tile,
								GetTileOwner(tile),
								axis == AXIS_X ? ROAD_Y : ROAD_X,
								town
							);
						}
					} else {
						if (GB(_m[tile].m5, 3, 2) == 0) {
							MakeClear(tile, CLEAR_GRASS, 3);
						} else {
							MakeCanal(tile, GetTileOwner(tile));
						}
					}
					SetBridgeMiddle(tile, axis);
				} else { // ramp
					Axis axis = (Axis)GB(_m[tile].m5, 0, 1);
					uint north_south = GB(_m[tile].m5, 5, 1);
					DiagDirection dir = ReverseDiagDir(XYNSToDiagDir(axis, north_south));
					TransportType type = (TransportType)GB(_m[tile].m5, 1, 2);

					_m[tile].m5 = 1 << 7 | type << 2 | dir;
				}
			}
		}
	}

	/* Divide MP_TUNNELBRIDGE into more tile types */
	if (CheckSavegameVersion(43)) {
		TileIndex tile;

		for (tile = 0; tile != MapSize(); tile++) {
			if (IsTileType(tile, MP_TUNNEL)) {
				if (HASBIT(_m[tile].m5, 7)) { /* Bridge */
					DiagDirection dd = GB(_m[tile].m5, 0, 2);
					SB(_m[tile].m5, 0, 2, 0);
					if (GB(_m[tile].m5, 2, 2) == 0) { /* Railway Bridge */
						SetTileType(tile, MP_RAILWAY_BRIDGE);
						if (dd == DIAGDIR_NE || dd == DIAGDIR_SW) {
							SETBIT(_m[tile].m5, 0);
						} else {
							SETBIT(_m[tile].m5, 1);
						}
					} else {
						SetTileType(tile, MP_STREET_BRIDGE);
					}
					CLRBIT(_m[tile].m5, 7);
					SB(_m[tile].m5, 2, 2, 0);
					SB(_m[tile].m4, 5, 2, dd);
				} else { /* Tunnel */
					SetTileType(tile, MP_TUNNEL);
				}
			}
		}
	}

	if (CheckSavegameVersion(42)) {
		Vehicle* v;
		FOR_ALL_VEHICLES(v) {
			if (v->type != VEH_Train && v->type != VEH_Road) continue;
			if (IsBridgeTile(v->tile)) {
				DiagDirection dir = GetBridgeRampDirection(v->tile);

				if (dir != DirToDiagDir(v->direction)) continue;
				switch (dir) {
					default: NOT_REACHED();
					case DIAGDIR_NE: if ((v->x_pos & 0xF) !=  0)            continue; break;
					case DIAGDIR_SE: if ((v->y_pos & 0xF) != TILE_SIZE - 1) continue; break;
					case DIAGDIR_SW: if ((v->x_pos & 0xF) != TILE_SIZE - 1) continue; break;
					case DIAGDIR_NW: if ((v->y_pos & 0xF) !=  0)            continue; break;
				}
			} else if (v->z_pos > GetSlopeZ(v->x_pos, v->y_pos)) {
				v->tile = GetNorthernBridgeEnd(v->tile);
			} else {
				continue;
			}
			if (v->type == VEH_Train) {
				v->u.rail.track = 0x40;
			} else {
				v->u.road.state = 0xFF;
			}
		}
	}

	/* Elrails got added in rev 24 */
	if (CheckSavegameVersion(24)) {
		Vehicle *v;
		uint i;
		TileIndex t;
		RailType min_rail = RAILTYPE_ELECTRIC;

		for (i = 0; i < lengthof(_engines); i++) {
			Engine *e = GetEngine(i);
			if (e->type == VEH_Train &&
					(e->railtype != RAILTYPE_RAIL || RailVehInfo(i)->engclass == 2)) {
				e->railtype++;
			}
		}

		FOR_ALL_VEHICLES(v) {
			if (v->type == VEH_Train) {
				RailType rt = GetEngine(v->engine_type)->railtype;

				v->u.rail.railtype = rt;
				if (rt == RAILTYPE_ELECTRIC) min_rail = RAILTYPE_RAIL;
			}
		}

		/* .. so we convert the entire map from normal to elrail (so maintain "fairness") */
		for (t = 0; t < MapSize(); t++) {
			switch (GetTileType(t)) {
				case MP_RAILWAY:
					SetRailType(t, UpdateRailType(GetRailType(t), min_rail));
					break;

				case MP_STREET:
					if (IsLevelCrossing(t)) {
						SetRailTypeCrossing(t, UpdateRailType(GetRailTypeCrossing(t), min_rail));
					}
					break;

				case MP_STATION:
					if (IsRailwayStation(t)) {
						SetRailType(t, UpdateRailType(GetRailType(t), min_rail));
					}
					break;

				case MP_TUNNEL:
					if (GetTunnelTransportType(t) == TRANSPORT_RAIL) SetRailType(t, UpdateRailType(GetRailType(t), min_rail));
					break;

				case MP_RAILWAY_BRIDGE:
					SetRailType(t, UpdateRailType(GetRailType(t), min_rail));
					break;

				default:
					break;
			}
		}

		FOR_ALL_VEHICLES(v) {
			if (v->type == VEH_Train && (IsFrontEngine(v) || IsFreeWagon(v))) TrainConsistChanged(v);
		}

	}

	/* In version 16.1 of the savegame a player can decide if trains, which get
	 * replaced, shall keep their old length. In all prior versions, just default
	 * to false */
	if (CheckSavegameVersionOldStyle(16, 1)) {
		FOR_ALL_PLAYERS(p) p->renew_keep_length = false;
	}

	/* 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 (CheckSavegameVersion(17)) {
		Waypoint *wp;

		FOR_ALL_WAYPOINTS(wp) {
			if (wp->deleted == 0) {
				const StationSpec *statspec = NULL;

				if (HASBIT(_m[wp->xy].m3, 4))
					statspec = GetCustomStationSpec(STAT_CLASS_WAYP, _m[wp->xy].m4 + 1);

				if (statspec != NULL) {
					wp->stat_id = _m[wp->xy].m4 + 1;
					wp->grfid = statspec->grfid;
					wp->localidx = statspec->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. */
		AfterLoadWaypoints();
	}

	/* From version 15, we moved a semaphore bit from bit 2 to bit 3 in m4, making
	 *  room for PBS. Now in version 21 move it back :P. */
	if (CheckSavegameVersion(21) && !CheckSavegameVersion(15)) {
		BEGIN_TILE_LOOP(tile, MapSizeX(), MapSizeY(), 0) {
			if (IsTileType(tile, MP_RAILWAY)) {
				if (HasSignals(tile)) {
					// convert PBS signals to combo-signals
					if (HASBIT(_m[tile].m4, 2)) SetSignalType(tile, SIGTYPE_COMBO);

					// move the signal variant back
					SetSignalVariant(tile, HASBIT(_m[tile].m4, 3) ? SIG_SEMAPHORE : SIG_ELECTRIC);
					CLRBIT(_m[tile].m4, 3);
				}

				// Clear PBS reservation on track
				if (!IsTileDepotType(tile, TRANSPORT_RAIL)) {
					SB(_m[tile].m4, 4, 4, 0);
				} else {
					CLRBIT(_m[tile].m3, 6);
				}
			}

			// Clear PBS reservation on crossing
			if (IsTileType(tile, MP_STREET) && IsLevelCrossing(tile))
				CLRBIT(_m[tile].m5, 0);

			// Clear PBS reservation on station
			if (IsTileType(tile, MP_STATION))
				CLRBIT(_m[tile].m3, 6);
		} END_TILE_LOOP(tile, MapSizeX(), MapSizeY(), 0);
	}

	if (CheckSavegameVersion(22))  UpdatePatches();

	if (CheckSavegameVersion(25)) {
		Vehicle *v;
		FOR_ALL_VEHICLES(v) {
			if (v->type == VEH_Road) {
				v->vehstatus &= ~0x40;
				v->u.road.slot = NULL;
				v->u.road.slot_age = 0;
			}
		}
	}

	if (CheckSavegameVersion(26)) {
		Station *st;
		FOR_ALL_STATIONS(st) {
			st->last_vehicle_type = VEH_Invalid;
		}
	}

	YapfNotifyTrackLayoutChange(INVALID_TILE, INVALID_TRACK);

	if (CheckSavegameVersion(34)) FOR_ALL_PLAYERS(p) ResetPlayerLivery(p);

	FOR_ALL_PLAYERS(p) p->avail_railtypes = GetPlayerRailtypes(p->index);

	if (!CheckSavegameVersion(27)) AfterLoadStations();

	{
		/* Set up the engine count for all players */
		Player *players[MAX_PLAYERS];
		int i;
		const Vehicle *v;

		for (i = 0; i < MAX_PLAYERS; i++) players[i] = GetPlayer(i);

		FOR_ALL_VEHICLES(v) {
			if (!IsEngineCountable(v)) continue;
			players[v->owner]->num_engines[v->engine_type]++;
		}
	}

	/* Time starts at 0 instead of 1920.
	 * Account for this in older games by adding an offset */
	if (CheckSavegameVersion(31)) {
		Station *st;
		Waypoint *wp;
		Engine *e;
		Player *player;
		Industry *i;
		Vehicle *v;

		_date += DAYS_TILL_ORIGINAL_BASE_YEAR;
		_cur_year += ORIGINAL_BASE_YEAR;

		FOR_ALL_STATIONS(st)    st->build_date += DAYS_TILL_ORIGINAL_BASE_YEAR;
		FOR_ALL_WAYPOINTS(wp)   wp->build_date += DAYS_TILL_ORIGINAL_BASE_YEAR;
		FOR_ALL_ENGINES(e)      e->intro_date  += DAYS_TILL_ORIGINAL_BASE_YEAR;
		FOR_ALL_PLAYERS(player) player->inaugurated_year += ORIGINAL_BASE_YEAR;
		FOR_ALL_INDUSTRIES(i)   i->last_prod_year        += ORIGINAL_BASE_YEAR;

		FOR_ALL_VEHICLES(v) {
			v->date_of_last_service += DAYS_TILL_ORIGINAL_BASE_YEAR;
			v->build_year += ORIGINAL_BASE_YEAR;
		}
	}

	/* From 32 on we save the industry who made the farmland.
	 *  To give this prettyness to old savegames, we remove all farmfields and
	 *  plant new ones. */
	if (CheckSavegameVersion(32)) {
		Industry *i;

		BEGIN_TILE_LOOP(tile_cur, MapSizeX(), MapSizeY(), 0) {
			if (IsTileType(tile_cur, MP_CLEAR) && IsClearGround(tile_cur, CLEAR_FIELDS)) {
				MakeClear(tile_cur, CLEAR_GRASS, 3);
			}
		} END_TILE_LOOP(tile_cur, MapSizeX(), MapSizeY(), 0)

		FOR_ALL_INDUSTRIES(i) {
			uint j;

			if (i->type == IT_FARM || i->type == IT_FARM_2) {
				for (j = 0; j != 50; j++) PlantRandomFarmField(i);
			}
		}
	}

	/* Setting no refit flags to all orders in savegames from before refit in orders were added */
	if (CheckSavegameVersion(36)) {
		Order *order;
		Vehicle *v;

		FOR_ALL_ORDERS(order) {
			order->refit_cargo   = CT_NO_REFIT;
			order->refit_subtype = CT_NO_REFIT;
		}

		FOR_ALL_VEHICLES(v) {
			v->current_order.refit_cargo   = CT_NO_REFIT;
			v->current_order.refit_subtype = CT_NO_REFIT;
		}
	}

	if (CheckSavegameVersion(37)) {
		ConvertNameArray();
	}

	/* from version 38 we have optional elrails, since we cannot know the
	 * preference of a user, let elrails enabled; it can be disabled manually */
	if (CheckSavegameVersion(38)) {
		_patches.disable_elrails = false; // enable elrails
		/* do the same as when elrails were enabled/disabled manually just now */
		SettingsDisableElrail(_patches.disable_elrails);
	}

	return true;
}

/** Reload all NewGRF files during a running game. This is a cut-down
 * version of AfterLoadGame().
 * XXX - We need to reset the vehicle position hash because with a non-empty
 * hash AfterLoadVehicles() will loop infinitely. We need AfterLoadVehicles()
 * to recalculate vehicle data as some NewGRF vehicle sets could have been
 * removed or added and changed statistics */
void ReloadNewGRFData(void)
{
	/* reload grf data */
	GfxLoadSprites();
	LoadStringWidthTable();
	/* reload vehicles */
	ResetVehiclePosHash();
	AfterLoadVehicles();
	/* update station and waypoint graphics */
	AfterLoadWaypoints();
	AfterLoadStations();
	/* redraw the whole screen */
	MarkWholeScreenDirty();
}