C++ SmallSet::Get方法代码示例

/**
 * 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);
		}
	}

}

/**
 * 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;
//.........这里部分代码省略.........