/**
* Update signals, starting at one side of a tile
* Will check tile next to this at opposite side too
*
* @see UpdateSignalsInBuffer()
* @param tile tile where we start
* @param side side of tile
* @param owner owner whose signals we will update
* @return the state of the signal segment
*/
SigSegState UpdateSignalsOnSegment(TileIndex tile, DiagDirection side, Owner owner)
{
assert(_globset.IsEmpty());
_globset.Add(tile, side);
return UpdateSignalsInBuffer(owner);
}
/**
* Add side of tile to signal update buffer
*
* @param tile tile where we start
* @param side side of tile
* @param owner owner whose signals we will update
*/
void AddSideToSignalBuffer(TileIndex tile, DiagDirection side, Owner owner)
{
/* do not allow signal updates for two companies in one run */
assert(_globset.IsEmpty() || owner == _last_owner);
_last_owner = owner;
_globset.Add(tile, side);
if (_globset.Items() >= SIG_GLOB_UPDATE) {
/* too many items, force update */
UpdateSignalsInBuffer(_last_owner);
_last_owner = INVALID_OWNER;
}
}
/**
* Update signals around segment in _tbuset
*
* @param flags info about segment
*/
static void UpdateSignalsAroundSegment(SigFlags flags)
{
TileIndex tile;
Trackdir trackdir;
while (_tbuset.Get(&tile, &trackdir)) {
assert(HasSignalOnTrackdir(tile, trackdir));
SignalType sig = GetSignalType(tile, TrackdirToTrack(trackdir));
SignalState newstate = SIGNAL_STATE_GREEN;
/* determine whether the new state is red */
if (flags & SF_TRAIN) {
/* train in the segment */
newstate = SIGNAL_STATE_RED;
} else {
/* is it a bidir combo? - then do not count its other signal direction as exit */
if (sig == SIGTYPE_COMBO && HasSignalOnTrackdir(tile, ReverseTrackdir(trackdir))) {
/* at least one more exit */
if ((flags & SF_EXIT2) &&
/* no green exit */
(!(flags & SF_GREEN) ||
/* only one green exit, and it is this one - so all other exits are red */
(!(flags & SF_GREEN2) && GetSignalStateByTrackdir(tile, ReverseTrackdir(trackdir)) == SIGNAL_STATE_GREEN))) {
newstate = SIGNAL_STATE_RED;
}
} else { // entry, at least one exit, no green exit
if (IsPresignalEntry(tile, TrackdirToTrack(trackdir)) && (flags & SF_EXIT) && !(flags & SF_GREEN)) newstate = SIGNAL_STATE_RED;
}
}
/* only when the state changes */
if (newstate != GetSignalStateByTrackdir(tile, trackdir)) {
if (IsPresignalExit(tile, TrackdirToTrack(trackdir))) {
/* for pre-signal exits, add block to the global set */
DiagDirection exitdir = TrackdirToExitdir(ReverseTrackdir(trackdir));
_globset.Add(tile, exitdir); // do not check for full global set, first update all signals
}
SetSignalStateByTrackdir(tile, trackdir, newstate);
MarkTileDirtyByTile(tile);
}
}
}
/**
* Add track to signal update buffer
*
* @param tile tile where we start
* @param track track at which ends we will update signals
* @param owner owner whose signals we will update
*/
void AddTrackToSignalBuffer(TileIndex tile, Track track, Owner owner)
{
static const DiagDirection _search_dir_1[] = {
DIAGDIR_NE, DIAGDIR_SE, DIAGDIR_NE, DIAGDIR_SE, DIAGDIR_SW, DIAGDIR_SE
};
static const DiagDirection _search_dir_2[] = {
DIAGDIR_SW, DIAGDIR_NW, DIAGDIR_NW, DIAGDIR_SW, DIAGDIR_NW, DIAGDIR_NE
};
/* do not allow signal updates for two companies in one run */
assert(_globset.IsEmpty() || owner == _last_owner);
_last_owner = owner;
_globset.Add(tile, _search_dir_1[track]);
_globset.Add(tile, _search_dir_2[track]);
if (_globset.Items() >= SIG_GLOB_UPDATE) {
/* too many items, force update */
UpdateSignalsInBuffer(_last_owner);
_last_owner = INVALID_OWNER;
}
}
/**
* Updates blocks in _globset buffer
*
* @param owner company whose signals we are updating
* @return state of the first block from _globset
* @pre Company::IsValidID(owner)
*/
static SigSegState UpdateSignalsInBuffer(Owner owner)
{
assert(Company::IsValidID(owner));
bool first = true; // first block?
SigSegState state = SIGSEG_FREE; // value to return
TileIndex tile;
DiagDirection dir;
while (_globset.Get(&tile, &dir)) {
assert(_tbuset.IsEmpty());
assert(_tbdset.IsEmpty());
/* After updating signal, data stored are always MP_RAILWAY with signals.
* Other situations happen when data are from outside functions -
* modification of railbits (including both rail building and removal),
* train entering/leaving block, train leaving depot...
*/
switch (GetTileType(tile)) {
case MP_TUNNELBRIDGE:
/* 'optimization assert' - do not try to update signals when it is not needed */
assert(GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL);
assert(dir == INVALID_DIAGDIR || dir == ReverseDiagDir(GetTunnelBridgeDirection(tile)));
_tbdset.Add(tile, INVALID_DIAGDIR); // we can safely start from wormhole centre
_tbdset.Add(GetOtherTunnelBridgeEnd(tile), INVALID_DIAGDIR);
break;
case MP_RAILWAY:
if (IsRailDepot(tile)) {
/* 'optimization assert' do not try to update signals in other cases */
assert(dir == INVALID_DIAGDIR || dir == GetRailDepotDirection(tile));
_tbdset.Add(tile, INVALID_DIAGDIR); // start from depot inside
break;
}
/* FALL THROUGH */
case MP_STATION:
case MP_ROAD:
if ((TrackStatusToTrackBits(GetTileTrackStatus(tile, TRANSPORT_RAIL, 0)) & _enterdir_to_trackbits[dir]) != TRACK_BIT_NONE) {
/* only add to set when there is some 'interesting' track */
_tbdset.Add(tile, dir);
_tbdset.Add(tile + TileOffsByDiagDir(dir), ReverseDiagDir(dir));
break;
}
/* FALL THROUGH */
default:
/* jump to next tile */
tile = tile + TileOffsByDiagDir(dir);
dir = ReverseDiagDir(dir);
if ((TrackStatusToTrackBits(GetTileTrackStatus(tile, TRANSPORT_RAIL, 0)) & _enterdir_to_trackbits[dir]) != TRACK_BIT_NONE) {
_tbdset.Add(tile, dir);
break;
}
/* happens when removing a rail that wasn't connected at one or both sides */
continue; // continue the while() loop
}
assert(!_tbdset.Overflowed()); // it really shouldn't overflow by these one or two items
assert(!_tbdset.IsEmpty()); // it wouldn't hurt anyone, but shouldn't happen too
SigFlags flags = ExploreSegment(owner);
if (first) {
first = false;
/* SIGSEG_FREE is set by default */
if (flags & SF_PBS) {
state = SIGSEG_PBS;
} else if ((flags & SF_TRAIN) || ((flags & SF_EXIT) && !(flags & SF_GREEN)) || (flags & SF_FULL)) {
state = SIGSEG_FULL;
}
}
/* do not do anything when some buffer was full */
if (flags & SF_FULL) {
ResetSets(); // free all sets
break;
}
UpdateSignalsAroundSegment(flags);
}
return state;
}
/**
* Search signal block
*
* @param owner owner whose signals we are updating
* @return SigFlags
*/
static SigFlags ExploreSegment(Owner owner)
{
SigFlags flags = SF_NONE;
TileIndex tile;
DiagDirection enterdir;
while (_tbdset.Get(&tile, &enterdir)) {
TileIndex oldtile = tile; // tile we are leaving
DiagDirection exitdir = enterdir == INVALID_DIAGDIR ? INVALID_DIAGDIR : ReverseDiagDir(enterdir); // expected new exit direction (for straight line)
switch (GetTileType(tile)) {
case MP_RAILWAY: {
if (GetTileOwner(tile) != owner) continue; // do not propagate signals on others' tiles (remove for tracksharing)
if (IsRailDepot(tile)) {
if (enterdir == INVALID_DIAGDIR) { // from 'inside' - train just entered or left the depot
if (!(flags & SF_TRAIN) && HasVehicleOnPos(tile, NULL, &TrainOnTileEnum)) flags |= SF_TRAIN;
exitdir = GetRailDepotDirection(tile);
tile += TileOffsByDiagDir(exitdir);
enterdir = ReverseDiagDir(exitdir);
break;
} else if (enterdir == GetRailDepotDirection(tile)) { // entered a depot
if (!(flags & SF_TRAIN) && HasVehicleOnPos(tile, NULL, &TrainOnTileEnum)) flags |= SF_TRAIN;
continue;
} else {
continue;
}
}
TrackBits tracks = GetTrackBits(tile); // trackbits of tile
TrackBits tracks_masked = (TrackBits)(tracks & _enterdir_to_trackbits[enterdir]); // only incidating trackbits
if (tracks == TRACK_BIT_HORZ || tracks == TRACK_BIT_VERT) { // there is exactly one incidating track, no need to check
tracks = tracks_masked;
/* If no train detected yet, and there is not no train -> there is a train -> set the flag */
if (!(flags & SF_TRAIN) && EnsureNoTrainOnTrackBits(tile, tracks).Failed()) flags |= SF_TRAIN;
} else {
if (tracks_masked == TRACK_BIT_NONE) continue; // no incidating track
if (!(flags & SF_TRAIN) && HasVehicleOnPos(tile, NULL, &TrainOnTileEnum)) flags |= SF_TRAIN;
}
if (HasSignals(tile)) { // there is exactly one track - not zero, because there is exit from this tile
Track track = TrackBitsToTrack(tracks_masked); // mask TRACK_BIT_X and Y too
if (HasSignalOnTrack(tile, track)) { // now check whole track, not trackdir
SignalType sig = GetSignalType(tile, track);
Trackdir trackdir = (Trackdir)FindFirstBit((tracks * 0x101) & _enterdir_to_trackdirbits[enterdir]);
Trackdir reversedir = ReverseTrackdir(trackdir);
/* add (tile, reversetrackdir) to 'to-be-updated' set when there is
* ANY conventional signal in REVERSE direction
* (if it is a presignal EXIT and it changes, it will be added to 'to-be-done' set later) */
if (HasSignalOnTrackdir(tile, reversedir)) {
if (IsPbsSignal(sig)) {
flags |= SF_PBS;
} else if (!_tbuset.Add(tile, reversedir)) {
return flags | SF_FULL;
}
}
if (HasSignalOnTrackdir(tile, trackdir) && !IsOnewaySignal(tile, track)) flags |= SF_PBS;
/* if it is a presignal EXIT in OUR direction and we haven't found 2 green exits yes, do special check */
if (!(flags & SF_GREEN2) && IsPresignalExit(tile, track) && HasSignalOnTrackdir(tile, trackdir)) { // found presignal exit
if (flags & SF_EXIT) flags |= SF_EXIT2; // found two (or more) exits
flags |= SF_EXIT; // found at least one exit - allow for compiler optimizations
if (GetSignalStateByTrackdir(tile, trackdir) == SIGNAL_STATE_GREEN) { // found green presignal exit
if (flags & SF_GREEN) flags |= SF_GREEN2;
flags |= SF_GREEN;
}
}
continue;
}
}
for (DiagDirection dir = DIAGDIR_BEGIN; dir < DIAGDIR_END; dir++) { // test all possible exit directions
if (dir != enterdir && (tracks & _enterdir_to_trackbits[dir])) { // any track incidating?
TileIndex newtile = tile + TileOffsByDiagDir(dir); // new tile to check
DiagDirection newdir = ReverseDiagDir(dir); // direction we are entering from
if (!MaybeAddToTodoSet(newtile, newdir, tile, dir)) return flags | SF_FULL;
}
}
continue; // continue the while() loop
}
case MP_STATION:
if (!HasStationRail(tile)) continue;
if (GetTileOwner(tile) != owner) continue;
if (DiagDirToAxis(enterdir) != GetRailStationAxis(tile)) continue; // different axis
if (IsStationTileBlocked(tile)) continue; // 'eye-candy' station tile
if (!(flags & SF_TRAIN) && HasVehicleOnPos(tile, NULL, &TrainOnTileEnum)) flags |= SF_TRAIN;
tile += TileOffsByDiagDir(exitdir);
break;
case MP_ROAD:
if (!IsLevelCrossing(tile)) continue;
if (GetTileOwner(tile) != owner) continue;
if (DiagDirToAxis(enterdir) == GetCrossingRoadAxis(tile)) continue; // different axis
if (!(flags & SF_TRAIN) && HasVehicleOnPos(tile, NULL, &TrainOnTileEnum)) flags |= SF_TRAIN;
tile += TileOffsByDiagDir(exitdir);
break;
case MP_TUNNELBRIDGE: {
if (GetTileOwner(tile) != owner) continue;
if (GetTunnelBridgeTransportType(tile) != TRANSPORT_RAIL) continue;
DiagDirection dir = GetTunnelBridgeDirection(tile);
if (enterdir == INVALID_DIAGDIR) { // incoming from the wormhole
if (!(flags & SF_TRAIN) && HasVehicleOnPos(tile, NULL, &TrainOnTileEnum)) flags |= SF_TRAIN;
enterdir = dir;
exitdir = ReverseDiagDir(dir);
tile += TileOffsByDiagDir(exitdir); // just skip to next tile
} else { // NOT incoming from the wormhole!
if (ReverseDiagDir(enterdir) != dir) continue;
if (!(flags & SF_TRAIN) && HasVehicleOnPos(tile, NULL, &TrainOnTileEnum)) flags |= SF_TRAIN;
tile = GetOtherTunnelBridgeEnd(tile); // just skip to exit tile
enterdir = INVALID_DIAGDIR;
exitdir = INVALID_DIAGDIR;
}
}
break;
default:
continue; // continue the while() loop
}
if (!MaybeAddToTodoSet(tile, enterdir, oldtile, exitdir)) return flags | SF_FULL;
}
return flags;
}
/**
* Perform some operations before adding data into Todo set
* The new and reverse direction is removed from Global set, because we are sure
* it doesn't need to be checked again
* Also, remove reverse direction from Todo set
* This is the 'core' part so the graph seaching won't enter any tile twice
*
* @param t1 tile we are entering
* @param d1 direction (tile side) we are entering
* @param t2 tile we are leaving
* @param d2 direction (tile side) we are leaving
* @return false iff the Todo buffer would be overrun
*/
static inline bool MaybeAddToTodoSet(TileIndex t1, DiagDirection d1, TileIndex t2, DiagDirection d2)
{
if (!CheckAddToTodoSet(t1, d1, t2, d2)) return true;
return _tbdset.Add(t1, d1);
}
