smatz@8238: /* $Id$ */
smatz@8238: 
smatz@8238: /** @file signal.cpp functions related to rail signals updating */
smatz@8238: 
smatz@8238: #include "stdafx.h"
smatz@8238: #include "openttd.h"
smatz@8238: #include "debug.h"
smatz@8238: #include "tile_cmd.h"
smatz@8238: #include "rail_map.h"
smatz@8238: #include "road_map.h"
smatz@8238: #include "station_map.h"
smatz@8238: #include "tunnelbridge_map.h"
smatz@8238: #include "vehicle_func.h"
smatz@8238: #include "train.h"
smatz@8238: #include "newgrf_station.h"
smatz@8238: #include "functions.h"
smatz@8238: #include "track_type.h"
smatz@8238: #include "track_func.h"
smatz@8238: #include "signal_func.h"
rubidium@8254: #include "player_func.h"
smatz@8238: 
smatz@8238: 
smatz@8238: /** these are the maximums used for updating signal blocks */
smatz@8238: enum {
smatz@8306: 	SIG_TBU_SIZE    =  64, ///< number of signals entering to block
smatz@8306: 	SIG_TBD_SIZE    = 256, ///< number of intersections - open nodes in current block
smatz@8306: 	SIG_GLOB_SIZE   = 128, ///< number of open blocks (block can be opened more times until detected)
smatz@8306: 	SIG_GLOB_UPDATE =  64, ///< how many items need to be in _globset to force update
smatz@8238: };
smatz@8238: 
smatz@8337: /* need to typecast to compile with MorphOS */
smatz@8337: assert_compile((int)SIG_GLOB_UPDATE <= (int)SIG_GLOB_SIZE);
smatz@8306: 
smatz@8238: /** incidating trackbits with given enterdir */
smatz@8238: static const TrackBitsByte _enterdir_to_trackbits[DIAGDIR_END] = {
smatz@8238: 	{TRACK_BIT_3WAY_NE},
smatz@8238: 	{TRACK_BIT_3WAY_SE},
smatz@8238: 	{TRACK_BIT_3WAY_SW},
smatz@8238: 	{TRACK_BIT_3WAY_NW}
smatz@8238: };
smatz@8238: 
smatz@8238: /** incidating trackdirbits with given enterdir */
smatz@8238: static const TrackdirBitsShort _enterdir_to_trackdirbits[DIAGDIR_END] = {
smatz@8238: 	{TRACKDIR_BIT_X_SW | TRACKDIR_BIT_UPPER_W | TRACKDIR_BIT_RIGHT_S},
smatz@8238: 	{TRACKDIR_BIT_Y_NW | TRACKDIR_BIT_LOWER_W | TRACKDIR_BIT_RIGHT_N},
smatz@8238: 	{TRACKDIR_BIT_X_NE | TRACKDIR_BIT_LOWER_E | TRACKDIR_BIT_LEFT_N},
smatz@8238: 	{TRACKDIR_BIT_Y_SE | TRACKDIR_BIT_UPPER_E | TRACKDIR_BIT_LEFT_S}
smatz@8238: };
smatz@8238: 
smatz@8238: /**
smatz@8238:  * Set containing 'items' items of 'tile and Tdir'
smatz@8238:  * No tree structure is used because it would cause
smatz@8238:  * slowdowns in most usual cases
smatz@8238:  */
smatz@8238: template <typename Tdir, uint items>
smatz@8238: struct SmallSet {
smatz@8238: private:
smatz@8238: 	uint n;           // actual number of units
smatz@8238: 	bool overflowed;  // did we try to oveflow the set?
smatz@8238: 	const char *name; // name, used for debugging purposes...
smatz@8238: 
smatz@8238: 	/** Element of set */
smatz@8238: 	struct SSdata {
smatz@8238: 		TileIndex tile;
smatz@8238: 		Tdir dir;
smatz@8238: 	} data[items];
smatz@8238: 
smatz@8238: public:
smatz@8238: 	/** Constructor - just set default values and 'name' */
smatz@8238: 	SmallSet(const char *name) : n(0), overflowed(false), name(name) { }
smatz@8238: 
smatz@8238: 	/** Reset variables to default values */
smatz@8238: 	void Reset()
smatz@8238: 	{
smatz@8238: 		this->n = 0;
smatz@8238: 		this->overflowed = false;
smatz@8238: 	}
smatz@8238: 
smatz@8238: 	/**
smatz@8238: 	 * Returns value of 'oveflowed'
smatz@8238: 	 * @return did we try to overflow the set?
smatz@8238: 	 */
smatz@8238: 	bool Overflowed()
smatz@8238: 	{
smatz@8238: 		return this->overflowed;
smatz@8238: 	}
smatz@8238: 
smatz@8238: 	/**
smatz@8238: 	 * Checks for empty set
smatz@8238: 	 * @return is the set empty?
smatz@8238: 	 */
smatz@8238: 	bool IsEmpty()
smatz@8238: 	{
smatz@8238: 		return this->n == 0;
smatz@8238: 	}
smatz@8238: 
smatz@8238: 	/**
smatz@8238: 	 * Checks for full set
smatz@8238: 	 * @return is the set full?
smatz@8238: 	 */
smatz@8238: 	bool IsFull()
smatz@8238: 	{
smatz@8238: 		return this->n == lengthof(data);
smatz@8238: 	}
smatz@8238: 
smatz@8238: 	/**
smatz@8306: 	 * Reads the number of items
smatz@8306: 	 * @return current number of items
smatz@8306: 	 */
smatz@8306: 	uint Items()
smatz@8306: 	{
smatz@8306: 		return this->n;
smatz@8306: 	}
smatz@8306: 
smatz@8306: 
smatz@8306: 	/**
smatz@8238: 	 * Tries to remove first instance of given tile and dir
smatz@8238: 	 * @param tile tile
smatz@8238: 	 * @param dir and dir to remove
smatz@8238: 	 * @return element was found and removed
smatz@8238: 	 */
smatz@8238: 	bool Remove(TileIndex tile, Tdir dir)
smatz@8238: 	{
smatz@8238: 		for (uint i = 0; i < this->n; i++) {
smatz@8238: 			if (this->data[i].tile == tile && this->data[i].dir == dir) {
smatz@8238: 				this->data[i] = this->data[--this->n];
smatz@8238: 				return true;
smatz@8238: 			}
smatz@8238: 		}
smatz@8238: 
smatz@8238: 		return false;
smatz@8238: 	}
smatz@8238: 
smatz@8238: 	/**
smatz@8238: 	 * Tries to find given tile and dir in the set
smatz@8238: 	 * @param tile tile
smatz@8238: 	 * @param dir and dir to find
smatz@8238: 	 * @return true iff the tile & dir elemnt was found
smatz@8238: 	 */
smatz@8238: 	bool IsIn(TileIndex tile, Tdir dir)
smatz@8238: 	{
smatz@8238: 		for (uint i = 0; i < this->n; i++) {
smatz@8238: 			if (this->data[i].tile == tile && this->data[i].dir == dir) return true;
smatz@8238: 		}
smatz@8238: 
smatz@8238: 		return false;
smatz@8238: 	}
smatz@8238: 
smatz@8238: 	/**
smatz@8238: 	 * Adds tile & dir into the set, checks for full set
smatz@8238: 	 * Sets the 'overflowed' flag if the set was full
smatz@8238: 	 * @param tile tile
smatz@8238: 	 * @param dir and dir to add
smatz@8238: 	 * @return true iff the item could be added (set wasn't full)
smatz@8238: 	 */
smatz@8238: 	bool Add(TileIndex tile, Tdir dir)
smatz@8238: 	{
smatz@8238: 		if (this->IsFull()) {
smatz@8238: 			overflowed = true;
smatz@8238: 			DEBUG(misc, 0, "SignalSegment too complex. Set %s is full (maximum %d)", name, items);
smatz@8238: 			return false; // set is full
smatz@8238: 		}
smatz@8238: 
smatz@8238: 		this->data[this->n].tile = tile;
smatz@8238: 		this->data[this->n].dir = dir;
smatz@8238: 		this->n++;
smatz@8238: 
smatz@8238: 		return true;
smatz@8238: 	}
smatz@8238: 
smatz@8238: 	/**
smatz@8238: 	 * Reads the last added element into the set
smatz@8238: 	 * @param tile pointer where tile is written to
smatz@8238: 	 * @param dir pointer where dir is written to
smatz@8238: 	 * @return false iff the set was empty
smatz@8238: 	 */
smatz@8238: 	bool Get(TileIndex *tile, Tdir *dir)
smatz@8238: 	{
smatz@8238: 		if (this->n == 0) return false;
smatz@8238: 
smatz@8238: 		this->n--;
smatz@8238: 		*tile = this->data[this->n].tile;
smatz@8238: 		*dir = this->data[this->n].dir;
smatz@8238: 
smatz@8238: 		return true;
smatz@8238: 	}
smatz@8238: };
smatz@8238: 
smatz@8238: static SmallSet<Trackdir, SIG_TBU_SIZE> _tbuset("_tbuset");         ///< set of signals that will be updated
smatz@8238: static SmallSet<DiagDirection, SIG_TBD_SIZE> _tbdset("_tbdset");    ///< set of open nodes in current signal block
smatz@8238: static SmallSet<DiagDirection, SIG_GLOB_SIZE> _globset("_globset"); ///< set of places to be updated in following runs
smatz@8238: 
smatz@8238: 
smatz@8238: /** Check whether there is a train on rail, not in a depot */
rubidium@9775: static Vehicle *TrainOnTileEnum(Vehicle *v, void *)
smatz@8238: {
smatz@8238: 	if (v->type != VEH_TRAIN || v->u.rail.track == TRACK_BIT_DEPOT) return NULL;
smatz@8238: 
smatz@8238: 	return v;
smatz@8238: }
smatz@8238: 
smatz@8238: 
smatz@8238: /**
smatz@8238:  * Perform some operations before adding data into Todo set
smatz@8238:  * The new and reverse direction is removed from _globset, because we are sure
smatz@8238:  * it doesn't need to be checked again
smatz@8238:  * Also, remove reverse direction from _tbdset
smatz@8238:  * This is the 'core' part so the graph seaching won't enter any tile twice
smatz@8238:  *
smatz@8238:  * @param t1 tile we are entering
smatz@8238:  * @param d1 direction (tile side) we are entering
smatz@8238:  * @param t2 tile we are leaving
smatz@8238:  * @param d2 direction (tile side) we are leaving
smatz@8238:  * @return false iff reverse direction was in Todo set
smatz@8238:  */
smatz@8238: static inline bool CheckAddToTodoSet(TileIndex t1, DiagDirection d1, TileIndex t2, DiagDirection d2)
smatz@8238: {
smatz@8238: 	_globset.Remove(t1, d1); // it can be in Global but not in Todo
smatz@8238: 	_globset.Remove(t2, d2); // remove in all cases
smatz@8238: 
smatz@8238: 	assert(!_tbdset.IsIn(t1, d1)); // it really shouldn't be there already
smatz@8238: 
smatz@8238: 	if (_tbdset.Remove(t2, d2)) return false;
smatz@8238: 
smatz@8238: 	return true;
smatz@8238: }
smatz@8238: 
smatz@8238: 
smatz@8238: /**
smatz@8238:  * Perform some operations before adding data into Todo set
smatz@8238:  * The new and reverse direction is removed from Global set, because we are sure
smatz@8238:  * it doesn't need to be checked again
smatz@8238:  * Also, remove reverse direction from Todo set
smatz@8238:  * This is the 'core' part so the graph seaching won't enter any tile twice
smatz@8238:  *
smatz@8238:  * @param t1 tile we are entering
smatz@8238:  * @param d1 direction (tile side) we are entering
smatz@8238:  * @param t2 tile we are leaving
smatz@8238:  * @param d2 direction (tile side) we are leaving
smatz@8238:  * @return false iff the Todo buffer would be overrun
smatz@8238:  */
smatz@8238: static inline bool MaybeAddToTodoSet(TileIndex t1, DiagDirection d1, TileIndex t2, DiagDirection d2)
smatz@8238: {
smatz@8238: 	if (!CheckAddToTodoSet(t1, d1, t2, d2)) return true;
smatz@8238: 
smatz@8238: 	return _tbdset.Add(t1, d1);
smatz@8238: }
smatz@8238: 
smatz@8238: 
smatz@8238: /** Current signal block state flags */
smatz@8238: enum SigFlags {
smatz@8238: 	SF_NONE   = 0,
smatz@8238: 	SF_TRAIN  = 1 << 0, ///< train found in segment
smatz@8238: 	SF_EXIT   = 1 << 1, ///< exitsignal found
smatz@8238: 	SF_EXIT2  = 1 << 2, ///< two or more exits found
smatz@8238: 	SF_GREEN  = 1 << 3, ///< green exitsignal found
smatz@8238: 	SF_GREEN2 = 1 << 4, ///< two or more green exits found
smatz@8238: 	SF_FULL   = 1 << 5, ///< some of buffers was full, do not continue
rubidium@9791: 	SF_PBS    = 1 << 6, ///< pbs signal found
smatz@8238: };
smatz@8238: 
smatz@8238: DECLARE_ENUM_AS_BIT_SET(SigFlags)
smatz@8238: 
smatz@8238: 
smatz@8238: /**
smatz@8238:  * Search signal block
smatz@8238:  *
smatz@8238:  * @param owner owner whose signals we are updating
smatz@8238:  * @return SigFlags
smatz@8238:  */
smatz@8238: static SigFlags ExploreSegment(Owner owner)
smatz@8238: {
smatz@8238: 	SigFlags flags = SF_NONE;
smatz@8238: 
smatz@8300: 	TileIndex tile;
smatz@8300: 	DiagDirection enterdir;
smatz@8238: 
smatz@8300: 	while (_tbdset.Get(&tile, &enterdir)) {
smatz@8238: 		TileIndex oldtile = tile; // tile we are leaving
smatz@8238: 		DiagDirection exitdir = enterdir == INVALID_DIAGDIR ? INVALID_DIAGDIR : ReverseDiagDir(enterdir); // expected new exit direction (for straight line)
smatz@8238: 
smatz@8238: 		switch (GetTileType(tile)) {
smatz@8238: 			case MP_RAILWAY: {
smatz@8238: 				if (GetTileOwner(tile) != owner) continue; // do not propagate signals on others' tiles (remove for tracksharing)
smatz@8238: 
smatz@8238: 				if (IsRailDepot(tile)) {
smatz@8238: 					if (enterdir == INVALID_DIAGDIR) { // from 'inside' - train just entered or left the depot
rubidium@9775: 						if (!(flags & SF_TRAIN) && VehicleFromPos(tile, NULL, &TrainOnTileEnum) != NULL) flags |= SF_TRAIN;
smatz@8238: 						exitdir = GetRailDepotDirection(tile);
smatz@8238: 						tile += TileOffsByDiagDir(exitdir);
smatz@8238: 						enterdir = ReverseDiagDir(exitdir);
smatz@8238: 						break;
smatz@8238: 					} else if (enterdir == GetRailDepotDirection(tile)) { // entered a depot
rubidium@9775: 						if (!(flags & SF_TRAIN) && VehicleFromPos(tile, NULL, &TrainOnTileEnum) != NULL) flags |= SF_TRAIN;
smatz@8238: 						continue;
smatz@8238: 					} else {
smatz@8238: 						continue;
smatz@8238: 					}
smatz@8238: 				}
smatz@8238: 
smatz@8238: 				if (GetRailTileType(tile) == RAIL_TILE_WAYPOINT) {
smatz@9565: 					if (GetWaypointAxis(tile) != DiagDirToAxis(enterdir)) continue;
rubidium@9775: 					if (!(flags & SF_TRAIN) && VehicleFromPos(tile, NULL, &TrainOnTileEnum) != NULL) flags |= SF_TRAIN;
smatz@8238: 					tile += TileOffsByDiagDir(exitdir);
smatz@8238: 					/* enterdir and exitdir stay the same */
smatz@8238: 					break;
smatz@8238: 				}
smatz@8238: 
smatz@8238: 				TrackBits tracks = GetTrackBits(tile); // trackbits of tile
smatz@8238: 				TrackBits tracks_masked = (TrackBits)(tracks & _enterdir_to_trackbits[enterdir]); // only incidating trackbits
smatz@8238: 
smatz@8238: 				if (tracks == TRACK_BIT_HORZ || tracks == TRACK_BIT_VERT) { // there is exactly one incidating track, no need to check
smatz@8238: 					tracks = tracks_masked;
rubidium@9775: 					if (!(flags & SF_TRAIN) && VehicleFromPos(tile, &tracks, &EnsureNoTrainOnTrackProc) != NULL) flags |= SF_TRAIN;
smatz@8238: 				} else {
smatz@8238: 					if (tracks_masked == TRACK_BIT_NONE) continue; // no incidating track
rubidium@9775: 					if (!(flags & SF_TRAIN) && VehicleFromPos(tile, NULL, &TrainOnTileEnum) != NULL) flags |= SF_TRAIN;
smatz@8238: 				}
smatz@8238: 
smatz@8238: 				if (HasSignals(tile)) { // there is exactly one track - not zero, because there is exit from this tile
smatz@8238: 					Track track = TrackBitsToTrack(tracks_masked); // mask TRACK_BIT_X and Y too
smatz@8238: 					if (HasSignalOnTrack(tile, track)) { // now check whole track, not trackdir
smatz@8238: 						SignalType sig = GetSignalType(tile, track);
smatz@8238: 						Trackdir trackdir = (Trackdir)FindFirstBit((tracks * 0x101) & _enterdir_to_trackdirbits[enterdir]);
smatz@8238: 						Trackdir reversedir = ReverseTrackdir(trackdir);
smatz@8238: 						/* add (tile, reversetrackdir) to 'to-be-updated' set when there is
rubidium@9791: 						 * ANY conventional signal in REVERSE direction
smatz@8238: 						 * (if it is a presignal EXIT and it changes, it will be added to 'to-be-done' set later) */
smatz@8238: 						if (HasSignalOnTrackdir(tile, reversedir)) {
rubidium@9791: 							if (IsPbsSignal(sig)) {
rubidium@9791: 								flags |= SF_PBS;
rubidium@9791: 							} else if (!_tbuset.Add(tile, reversedir)) {
rubidium@9791: 								return flags | SF_FULL;
rubidium@9791: 							}
smatz@8238: 						}
rubidium@9791: 						if (HasSignalOnTrackdir(tile, trackdir) && !IsOnewaySignal(tile, track)) flags |= SF_PBS;
rubidium@9791: 
smatz@8238: 						/* if it is a presignal EXIT in OUR direction and we haven't found 2 green exits yes, do special check */
rubidium@9791: 						if (!(flags & SF_GREEN2) && IsPresignalExit(tile, track) && HasSignalOnTrackdir(tile, trackdir)) { // found presignal exit
smatz@8238: 							if (flags & SF_EXIT) flags |= SF_EXIT2; // found two (or more) exits
smatz@8238: 							flags |= SF_EXIT; // found at least one exit - allow for compiler optimizations
smatz@8238: 							if (GetSignalStateByTrackdir(tile, trackdir) == SIGNAL_STATE_GREEN) { // found green presignal exit
smatz@8238: 								if (flags & SF_GREEN) flags |= SF_GREEN2;
smatz@8238: 								flags |= SF_GREEN;
smatz@8238: 							}
smatz@8238: 						}
rubidium@9791: 
smatz@8238: 						continue;
smatz@8238: 					}
smatz@8238: 				}
smatz@8238: 
smatz@8238: 				for (DiagDirection dir = DIAGDIR_BEGIN; dir < DIAGDIR_END; dir++) { // test all possible exit directions
smatz@8238: 					if (dir != enterdir && tracks & _enterdir_to_trackbits[dir]) { // any track incidating?
smatz@8238: 						TileIndex newtile = tile + TileOffsByDiagDir(dir);  // new tile to check
smatz@8238: 						DiagDirection newdir = ReverseDiagDir(dir); // direction we are entering from
smatz@8238: 						if (!MaybeAddToTodoSet(newtile, newdir, tile, dir)) return flags | SF_FULL;
smatz@8238: 					}
smatz@8238: 				}
smatz@8238: 
smatz@8238: 				continue; // continue the while() loop
smatz@8238: 				}
smatz@8238: 
smatz@8238: 			case MP_STATION:
smatz@8238: 				if (!IsRailwayStation(tile)) continue;
smatz@8238: 				if (GetTileOwner(tile) != owner) continue;
smatz@8238: 				if (DiagDirToAxis(enterdir) != GetRailStationAxis(tile)) continue; // different axis
smatz@8238: 				if (IsStationTileBlocked(tile)) continue; // 'eye-candy' station tile
smatz@8238: 
rubidium@9775: 				if (!(flags & SF_TRAIN) && VehicleFromPos(tile, NULL, &TrainOnTileEnum) != NULL) flags |= SF_TRAIN;
smatz@8238: 				tile += TileOffsByDiagDir(exitdir);
smatz@8238: 				break;
smatz@8238: 
smatz@8238: 			case MP_ROAD:
smatz@8238: 				if (!IsLevelCrossing(tile)) continue;
smatz@8238: 				if (GetTileOwner(tile) != owner) continue;
smatz@8238: 				if (DiagDirToAxis(enterdir) == GetCrossingRoadAxis(tile)) continue; // different axis
smatz@8238: 
rubidium@9775: 				if (!(flags & SF_TRAIN) && VehicleFromPos(tile, NULL, &TrainOnTileEnum) != NULL) flags |= SF_TRAIN;
smatz@8238: 				tile += TileOffsByDiagDir(exitdir);
smatz@8238: 				break;
smatz@8238: 
smatz@8238: 			case MP_TUNNELBRIDGE: {
smatz@8238: 				if (GetTileOwner(tile) != owner) continue;
smatz@8238: 				if (GetTunnelBridgeTransportType(tile) != TRANSPORT_RAIL) continue;
smatz@8238: 				DiagDirection dir = GetTunnelBridgeDirection(tile);
smatz@8238: 
smatz@8238: 				if (enterdir == INVALID_DIAGDIR) { // incoming from the wormhole
rubidium@9775: 					if (!(flags & SF_TRAIN) && VehicleFromPos(tile, NULL, &TrainOnTileEnum) != NULL) flags |= SF_TRAIN;
smatz@8238: 					enterdir = dir;
smatz@8238: 					exitdir = ReverseDiagDir(dir);
smatz@8238: 					tile += TileOffsByDiagDir(exitdir); // just skip to next tile
smatz@8238: 				} else { // NOT incoming from the wormhole!
smatz@8238: 					if (ReverseDiagDir(enterdir) != dir) continue;
rubidium@9775: 					if (!(flags & SF_TRAIN) && VehicleFromPos(tile, NULL, &TrainOnTileEnum) != NULL) flags |= SF_TRAIN;
smatz@8238: 					tile = GetOtherTunnelBridgeEnd(tile); // just skip to exit tile
smatz@8238: 					enterdir = INVALID_DIAGDIR;
smatz@8238: 					exitdir = INVALID_DIAGDIR;
smatz@8238: 				}
smatz@8238: 				}
smatz@8238: 				break;
smatz@8238: 
smatz@8238: 			default:
smatz@8238: 				continue; // continue the while() loop
smatz@8238: 		}
smatz@8238: 
smatz@8238: 		if (!MaybeAddToTodoSet(tile, enterdir, oldtile, exitdir)) return flags | SF_FULL;
smatz@8238: 	}
smatz@8238: 
smatz@8238: 	return flags;
smatz@8238: }
smatz@8238: 
smatz@8238: 
smatz@8238: /**
smatz@8238:  * Update signals around segment in _tbuset
smatz@8238:  *
smatz@8238:  * @param flags info about segment
smatz@8238:  */
smatz@8238: static void UpdateSignalsAroundSegment(SigFlags flags)
smatz@8238: {
smatz@8300: 	TileIndex tile;
smatz@8300: 	Trackdir trackdir;
smatz@8238: 
smatz@8300: 	while (_tbuset.Get(&tile, &trackdir)) {
smatz@8238: 		assert(HasSignalOnTrackdir(tile, trackdir));
smatz@8238: 
smatz@8238: 		SignalType sig = GetSignalType(tile, TrackdirToTrack(trackdir));
smatz@8238: 		SignalState newstate = SIGNAL_STATE_GREEN;
smatz@8238: 
smatz@8238: 		/* determine whether the new state is red */
smatz@8238: 		if (flags & SF_TRAIN) {
smatz@8238: 			/* train in the segment */
smatz@8238: 			newstate = SIGNAL_STATE_RED;
smatz@8238: 		} else {
rubidium@8970: 			/* is it a bidir combo? - then do not count its other signal direction as exit */
smatz@8238: 			if (sig == SIGTYPE_COMBO && HasSignalOnTrackdir(tile, ReverseTrackdir(trackdir))) {
smatz@8238: 				/* at least one more exit */
smatz@8238: 				if (flags & SF_EXIT2 &&
rubidium@8970: 						/* no green exit */
smatz@8238: 						(!(flags & SF_GREEN) ||
smatz@8238: 						/* only one green exit, and it is this one - so all other exits are red */
smatz@8238: 						(!(flags & SF_GREEN2) && GetSignalStateByTrackdir(tile, ReverseTrackdir(trackdir)) == SIGNAL_STATE_GREEN))) {
smatz@8238: 					newstate = SIGNAL_STATE_RED;
smatz@8238: 				}
smatz@8238: 			} else { // entry, at least one exit, no green exit
rubidium@9791: 				if (IsPresignalEntry(tile, TrackdirToTrack(trackdir)) && flags & SF_EXIT && !(flags & SF_GREEN)) newstate = SIGNAL_STATE_RED;
smatz@8238: 			}
smatz@8238: 		}
smatz@8238: 
smatz@8238: 		/* only when the state changes */
smatz@8238: 		if (newstate != GetSignalStateByTrackdir(tile, trackdir)) {
rubidium@9791: 			if (IsPresignalExit(tile, TrackdirToTrack(trackdir))) {
smatz@8238: 				/* for pre-signal exits, add block to the global set */
smatz@8238: 				DiagDirection exitdir = TrackdirToExitdir(ReverseTrackdir(trackdir));
smatz@8238: 				_globset.Add(tile, exitdir); // do not check for full global set, first update all signals
smatz@8238: 			}
smatz@8238: 			SetSignalStateByTrackdir(tile, trackdir, newstate);
smatz@8238: 			MarkTileDirtyByTile(tile);
smatz@8238: 		}
smatz@8238: 	}
smatz@8238: 
smatz@8238: }
smatz@8238: 
smatz@8238: 
smatz@8238: /** Reset all sets after one set overflowed */
smatz@8238: static inline void ResetSets()
smatz@8238: {
smatz@8238: 	_tbuset.Reset();
smatz@8238: 	_tbdset.Reset();
smatz@8238: 	_globset.Reset();
smatz@8238: }
smatz@8238: 
smatz@8238: 
smatz@8238: /**
smatz@8238:  * Updates blocks in _globset buffer
smatz@8238:  *
smatz@8300:  * @param owner player whose signals we are updating
smatz@9323:  * @return state of the first block from _globset
rubidium@9652:  * @pre IsValidPlayerID(owner)
smatz@8238:  */
smatz@9222: static SigSegState UpdateSignalsInBuffer(Owner owner)
smatz@8238: {
rubidium@9652: 	assert(IsValidPlayerID(owner));
smatz@8300: 
smatz@8238: 	bool first = true;  // first block?
smatz@9222: 	SigSegState state = SIGSEG_FREE; // value to return
smatz@8238: 
smatz@8251: 	TileIndex tile;
smatz@8251: 	DiagDirection dir;
smatz@8251: 
smatz@8251: 	while (_globset.Get(&tile, &dir)) {
smatz@8238: 		assert(_tbuset.IsEmpty());
smatz@8238: 		assert(_tbdset.IsEmpty());
smatz@8238: 
smatz@8238: 		/* After updating signal, data stored are always MP_RAILWAY with signals.
smatz@8238: 		 * Other situations happen when data are from outside functions -
smatz@8238: 		 * modification of railbits (including both rail building and removal),
smatz@8238: 		 * train entering/leaving block, train leaving depot...
smatz@8238: 		 */
smatz@8238: 		switch (GetTileType(tile)) {
smatz@8238: 			case MP_TUNNELBRIDGE:
smatz@8238: 				/* 'optimization assert' - do not try to update signals when it is not needed */
smatz@8238: 				assert(GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL);
smatz@8238: 				assert(dir == INVALID_DIAGDIR || dir == ReverseDiagDir(GetTunnelBridgeDirection(tile)));
smatz@8238: 				_tbdset.Add(tile, INVALID_DIAGDIR);  // we can safely start from wormhole centre
smatz@8238: 				_tbdset.Add(GetOtherTunnelBridgeEnd(tile), INVALID_DIAGDIR);
smatz@8238: 				break;
smatz@8238: 
smatz@8238: 			case MP_RAILWAY:
smatz@8238: 				if (IsRailDepot(tile)) {
smatz@8238: 					/* 'optimization assert' do not try to update signals in other cases */
smatz@8238: 					assert(dir == INVALID_DIAGDIR || dir == GetRailDepotDirection(tile));
smatz@8238: 					_tbdset.Add(tile, INVALID_DIAGDIR); // start from depot inside
smatz@8238: 					break;
smatz@8238: 				}
smatz@8238: 				/* FALLTHROUGH */
smatz@8238: 			case MP_STATION:
smatz@8238: 			case MP_ROAD:
frosch@8616: 				if ((TrackStatusToTrackBits(GetTileTrackStatus(tile, TRANSPORT_RAIL, 0)) & _enterdir_to_trackbits[dir]) != TRACK_BIT_NONE) {
rubidium@8970: 					/* only add to set when there is some 'interesting' track */
smatz@8238: 					_tbdset.Add(tile, dir);
smatz@8238: 					_tbdset.Add(tile + TileOffsByDiagDir(dir), ReverseDiagDir(dir));
smatz@8238: 					break;
smatz@8238: 				}
smatz@8238: 				/* FALLTHROUGH */
smatz@8238: 			default:
smatz@8238: 				/* jump to next tile */
smatz@8238: 				tile = tile + TileOffsByDiagDir(dir);
smatz@8238: 				dir = ReverseDiagDir(dir);
frosch@8616: 				if ((TrackStatusToTrackBits(GetTileTrackStatus(tile, TRANSPORT_RAIL, 0)) & _enterdir_to_trackbits[dir]) != TRACK_BIT_NONE) {
smatz@8238: 					_tbdset.Add(tile, dir);
smatz@8238: 					break;
smatz@8238: 				}
smatz@8238: 				/* happens when removing a rail that wasn't connected at one or both sides */
smatz@8238: 				continue; // continue the while() loop
smatz@8238: 		}
smatz@8238: 
smatz@8238: 		assert(!_tbdset.Overflowed()); // it really shouldn't overflow by these one or two items
smatz@8238: 		assert(!_tbdset.IsEmpty()); // it wouldn't hurt anyone, but shouldn't happen too
smatz@8238: 
smatz@8238: 		SigFlags flags = ExploreSegment(owner);
smatz@8238: 
smatz@8238: 		if (first) {
smatz@8238: 			first = false;
rubidium@9818: 			/* SIGSEG_FREE is set by default */
rubidium@9818: 			if (flags & SF_PBS) {
rubidium@9818: 				state = SIGSEG_PBS;
rubidium@9818: 			} else if (flags & SF_TRAIN || (flags & SF_EXIT && !(flags & SF_GREEN)) || flags & SF_FULL) {
smatz@9222: 				state = SIGSEG_FULL;
smatz@9222: 			}
smatz@8238: 		}
smatz@8238: 
smatz@8238: 		/* do not do anything when some buffer was full */
smatz@8246: 		if (flags & SF_FULL) {
smatz@8246: 			ResetSets(); // free all sets
smatz@8246: 			break;
smatz@8246: 		}
smatz@8238: 
smatz@8238: 		UpdateSignalsAroundSegment(flags);
smatz@8238: 	}
smatz@8238: 
smatz@8238: 	return state;
smatz@8238: }
smatz@8238: 
smatz@8238: 
smatz@8306: static Owner _last_owner = INVALID_OWNER; ///< last owner whose track was put into _globset
smatz@8306: 
smatz@8306: 
smatz@8306: /**
smatz@8306:  * Update signals in buffer
smatz@8306:  * Called from 'outside'
smatz@8306:  */
smatz@8306: void UpdateSignalsInBuffer()
smatz@8306: {
smatz@8306: 	if (!_globset.IsEmpty()) {
smatz@8306: 		UpdateSignalsInBuffer(_last_owner);
smatz@8306: 		_last_owner = INVALID_OWNER; // invalidate
smatz@8306: 	}
smatz@8306: }
smatz@8306: 
smatz@8306: 
smatz@8306: /**
smatz@8306:  * Add track to signal update buffer
smatz@8306:  *
smatz@8306:  * @param tile tile where we start
smatz@8306:  * @param track track at which ends we will update signals
smatz@8306:  * @param owner owner whose signals we will update
smatz@8306:  */
smatz@8306: void AddTrackToSignalBuffer(TileIndex tile, Track track, Owner owner)
smatz@8306: {
smatz@8306: 	static const DiagDirection _search_dir_1[] = {
smatz@8306: 		DIAGDIR_NE, DIAGDIR_SE, DIAGDIR_NE, DIAGDIR_SE, DIAGDIR_SW, DIAGDIR_SE
smatz@8306: 	};
smatz@8306: 	static const DiagDirection _search_dir_2[] = {
smatz@8306: 		DIAGDIR_SW, DIAGDIR_NW, DIAGDIR_NW, DIAGDIR_SW, DIAGDIR_NW, DIAGDIR_NE
smatz@8306: 	};
smatz@8306: 
smatz@8306: 	/* do not allow signal updates for two players in one run */
smatz@8306: 	assert(_globset.IsEmpty() || owner == _last_owner);
smatz@8306: 
smatz@8306: 	_last_owner = owner;
smatz@8306: 
smatz@8306: 	_globset.Add(tile, _search_dir_1[track]);
smatz@8306: 	_globset.Add(tile, _search_dir_2[track]);
smatz@8306: 
smatz@8306: 	if (_globset.Items() >= SIG_GLOB_UPDATE) {
smatz@8306: 		/* too many items, force update */
smatz@8306: 		UpdateSignalsInBuffer(_last_owner);
smatz@8306: 		_last_owner = INVALID_OWNER;
smatz@8306: 	}
smatz@8306: }
smatz@8306: 
smatz@8306: 
smatz@8306: /**
smatz@8306:  * Add side of tile to signal update buffer
smatz@8306:  *
smatz@8306:  * @param tile tile where we start
smatz@8306:  * @param side side of tile
smatz@8306:  * @param owner owner whose signals we will update
smatz@8306:  */
smatz@8306: void AddSideToSignalBuffer(TileIndex tile, DiagDirection side, Owner owner)
smatz@8306: {
smatz@8306: 	/* do not allow signal updates for two players in one run */
smatz@8306: 	assert(_globset.IsEmpty() || owner == _last_owner);
smatz@8306: 
smatz@8306: 	_last_owner = owner;
smatz@8306: 
smatz@8306: 	_globset.Add(tile, side);
smatz@8306: 
smatz@8306: 	if (_globset.Items() >= SIG_GLOB_UPDATE) {
smatz@8306: 		/* too many items, force update */
smatz@8306: 		UpdateSignalsInBuffer(_last_owner);
smatz@8306: 		_last_owner = INVALID_OWNER;
smatz@8306: 	}
smatz@8306: }
smatz@8306: 
smatz@8238: /**
smatz@8238:  * Update signals, starting at one side of a tile
smatz@8238:  * Will check tile next to this at opposite side too
smatz@8238:  *
smatz@8238:  * @see UpdateSignalsInBuffer()
smatz@8238:  * @param tile tile where we start
smatz@8238:  * @param side side of tile
smatz@8300:  * @param owner owner whose signals we will update
smatz@9323:  * @return the state of the signal segment
smatz@8238:  */
smatz@9222: SigSegState UpdateSignalsOnSegment(TileIndex tile, DiagDirection side, Owner owner)
smatz@8238: {
smatz@8238: 	assert(_globset.IsEmpty());
smatz@8238: 	_globset.Add(tile, side);
smatz@8238: 
smatz@8300: 	return UpdateSignalsInBuffer(owner);
smatz@8238: }
smatz@8238: 
smatz@8238: 
smatz@8238: /**
smatz@8238:  * Update signals at segments that are at both ends of
smatz@8238:  * given (existent or non-existent) track
smatz@8238:  *
smatz@8238:  * @see UpdateSignalsInBuffer()
smatz@8238:  * @param tile tile where we start
smatz@8238:  * @param track track at which ends we will update signals
smatz@8300:  * @param owner owner whose signals we will update
smatz@8238:  */
smatz@8300: void SetSignalsOnBothDir(TileIndex tile, Track track, Owner owner)
smatz@8238: {
smatz@8238: 	assert(_globset.IsEmpty());
smatz@8238: 
smatz@8306: 	AddTrackToSignalBuffer(tile, track, owner);
smatz@8300: 	UpdateSignalsInBuffer(owner);
smatz@8238: }