# signal.cpp File Reference

functions related to rail signals updating More...

`#include "stdafx.h"`
`#include "debug.h"`
`#include "station_map.h"`
`#include "tunnelbridge_map.h"`
`#include "vehicle_func.h"`
`#include "vehicle_base.h"`
`#include "functions.h"`

Go to the source code of this file.

## Data Structures

struct | SmallSet< Tdir, items >
| Set containing 'items' items of 'tile and Tdir' No tree structure is used because it would cause slowdowns in most usual cases. More...
struct | SmallSet< Tdir, items >::SSdata
| Element of set. More...

## Enumerations

enum | { SIG_TBU_SIZE = 64, SIG_TBD_SIZE = 256, SIG_GLOB_SIZE = 128, SIG_GLOB_UPDATE = 64 }
| these are the maximums used for updating signal blocks More...
enum | SigFlags { SF_NONE = 0, SF_TRAIN = 1 << 0, SF_EXIT = 1 << 1, SF_EXIT2 = 1 << 2, SF_GREEN = 1 << 3, SF_GREEN2 = 1 << 4, SF_FULL = 1 << 5, SF_PBS = 1 << 6 }
| Current signal block state flags. More...

## Functions

| assert_compile ((int) SIG_GLOB_UPDATE<=(int) SIG_GLOB_SIZE)
static Vehicle * | TrainOnTileEnum (Vehicle *v, void *)
| Check whether there is a train on rail, not in a depot.
static bool | CheckAddToTodoSet (TileIndex t1, DiagDirection d1, TileIndex t2, DiagDirection d2)
| Perform some operations before adding data into Todo set The new and reverse direction is removed from _globset, because we are sure it doesn't need to be checked again Also, remove reverse direction from _tbdset This is the 'core' part so the graph seaching won't enter any tile twice.
static bool | MaybeAddToTodoSet (TileIndex t1, DiagDirection d1, TileIndex t2, DiagDirection d2)
| 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.
static SigFlags | ExploreSegment (Owner owner)
| Search signal block.
static void | UpdateSignalsAroundSegment (SigFlags flags)
| Update signals around segment in _tbuset.
static void | ResetSets ()
| Reset all sets after one set overflowed.
static SigSegState | UpdateSignalsInBuffer (Owner owner)
| Updates blocks in _globset buffer.
void | UpdateSignalsInBuffer ()
| Update signals in buffer Called from 'outside'.
void | AddTrackToSignalBuffer (TileIndex tile, Track track, Owner owner)
| Add track to signal update buffer.
void | AddSideToSignalBuffer (TileIndex tile, DiagDirection side, Owner owner)
| Add side of tile to signal update buffer.
SigSegState | UpdateSignalsOnSegment (TileIndex tile, DiagDirection side, Owner owner)
| Update signals, starting at one side of a tile Will check tile next to this at opposite side too.
void | SetSignalsOnBothDir (TileIndex tile, Track track, Owner owner)
| Update signals at segments that are at both ends of given (existent or non-existent) track.

## Variables

static const TrackBitsByte | _enterdir_to_trackbits [DIAGDIR_END]
| incidating trackbits with given enterdir
static const TrackdirBitsShort | _enterdir_to_trackdirbits [DIAGDIR_END]
| incidating trackdirbits with given enterdir
static SmallSet< Trackdir, SIG_TBU_SIZE > | _tbuset ("_tbuset")
| set of signals that will be updated
static SmallSet< DiagDirection, SIG_TBD_SIZE > | _tbdset ("_tbdset")
| set of open nodes in current signal block
static SmallSet< DiagDirection, SIG_GLOB_SIZE > | _globset ("_globset")
| set of places to be updated in following runs
static Owner | _last_owner = INVALID_OWNER
| last owner whose track was put into _globset

## Detailed Description

functions related to rail signals updating

Definition in file signal.cpp.

## Enumeration Type Documentation

anonymous enum

these are the maximums used for updating signal blocks

Enumerator:

  SIG_TBU_SIZE | number of signals entering to block
  SIG_TBD_SIZE | number of intersections - open nodes in current block
  SIG_GLOB_SIZE | number of open blocks (block can be opened more times until detected)
  SIG_GLOB_UPDATE | how many items need to be in _globset to force update

Definition at line 15 of file signal.cpp.

enum SigFlags

Current signal block state flags.

Enumerator:

  SF_TRAIN | train found in segment
  SF_EXIT | exitsignal found
  SF_EXIT2 | two or more exits found
  SF_GREEN | green exitsignal found
  SF_GREEN2 | two or more green exits found
  SF_FULL | some of buffers was full, do not continue
  SF_PBS | pbs signal found

Definition at line 242 of file signal.cpp.

## Function Documentation

void AddSideToSignalBuffer | ( | TileIndex | tile,
|  | DiagDirection | side,
|  | Owner | owner |
| ) |  |  |

Add side of tile to signal update buffer.

Parameters:

  | tile | tile where we start
  | side | side of tile
  | owner | owner whose signals we will update

Definition at line 611 of file signal.cpp.

References _globset, INVALID_OWNER, SIG_GLOB_UPDATE, and UpdateSignalsInBuffer().

Referenced by CmdBuildBridge(), CmdBuildTrainDepot(), and CmdBuildTunnel().

void AddTrackToSignalBuffer | ( | TileIndex | tile,
|  | Track | track,
|  | Owner | owner |
| ) |  |  |

Add track to signal update buffer.

Parameters:

  | tile | tile where we start
  | track | track at which ends we will update signals
  | owner | owner whose signals we will update

Definition at line 579 of file signal.cpp.

References _globset, DIAGDIR_NE, DIAGDIR_NW, DIAGDIR_SE, DIAGDIR_SW, INVALID_OWNER, SIG_GLOB_UPDATE, and UpdateSignalsInBuffer().

Referenced by CmdBuildRailroadStation(), CmdBuildSingleRail(), CmdBuildSingleSignal(), CmdRemoveFromRailroadStation(), CmdRemoveSingleRail(), CmdRemoveSingleSignal(), RemoveTrainWaypoint(), and SetSignalsOnBothDir().

static bool CheckAddToTodoSet | ( | TileIndex | t1,
|  | DiagDirection | d1,
|  | TileIndex | t2,
|  | DiagDirection | d2 |
| ) |  |  | `[inline, static]`

Perform some operations before adding data into Todo set The new and reverse direction is removed from _globset, because we are sure it doesn't need to be checked again Also, remove reverse direction from _tbdset This is the 'core' part so the graph seaching won't enter any tile twice.

Parameters:

  | t1 | tile we are entering
  | d1 | direction (tile side) we are entering
  | t2 | tile we are leaving
  | d2 | direction (tile side) we are leaving

Returns:
  false iff reverse direction was in Todo set

Definition at line 207 of file signal.cpp.

References _globset, and _tbdset.

Referenced by MaybeAddToTodoSet().

static SigFlags ExploreSegment | ( | Owner | owner | ) | `[static]`

Search signal block.

Parameters:

  | owner | owner whose signals we are updating

Returns:
  SigFlags

Definition at line 262 of file signal.cpp.

References _tbdset, _tbuset, DIAGDIR_BEGIN, DIAGDIR_END, DiagDirToAxis(), FindFirstBit(), GetOtherTunnelBridgeEnd(), GetRailDepotDirection(), GetRailTileType(), GetSignalStateByTrackdir(), GetTileOwner(), GetTileType(), GetTrackBits(), GetTunnelBridgeDirection(), GetTunnelBridgeTransportType(), GetWaypointAxis(), HasSignalOnTrack(), HasSignalOnTrackdir(), HasSignals(), HasVehicleOnPos(), INVALID_DIAGDIR, IsOnewaySignal(), IsRailDepot(), MaybeAddToTodoSet(), MP_RAILWAY, MP_ROAD, MP_STATION, MP_TUNNELBRIDGE, RAIL_TILE_WAYPOINT, ReverseDiagDir(), ReverseTrackdir(), SF_EXIT, SF_EXIT2, SF_FULL, SF_GREEN, SF_GREEN2, SF_PBS, SF_TRAIN, SIGNAL_STATE_GREEN, TileOffsByDiagDir(), TRACK_BIT_HORZ, TRACK_BIT_NONE, TRACK_BIT_VERT, TrackBitsToTrack(), TrainOnTileEnum(), and TRANSPORT_RAIL.

Referenced by UpdateSignalsInBuffer().

static bool MaybeAddToTodoSet | ( | TileIndex | t1,
|  | DiagDirection | d1,
|  | TileIndex | t2,
|  | DiagDirection | d2 |
| ) |  |  | `[inline, static]`

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.

Parameters:

  | t1 | tile we are entering
  | d1 | direction (tile side) we are entering
  | t2 | tile we are leaving
  | d2 | direction (tile side) we are leaving

Returns:
  false iff the Todo buffer would be overrun

Definition at line 233 of file signal.cpp.

References _tbdset, and CheckAddToTodoSet().

Referenced by ExploreSegment().

void SetSignalsOnBothDir | ( | TileIndex | tile,
|  | Track | track,
|  | Owner | owner |
| ) |  |  |

Update signals at segments that are at both ends of given (existent or non-existent) track.

See also:
  UpdateSignalsInBuffer()

Parameters:

  | tile | tile where we start
  | track | track at which ends we will update signals
  | owner | owner whose signals we will update

Definition at line 655 of file signal.cpp.

References _globset, AddTrackToSignalBuffer(), and UpdateSignalsInBuffer().

Referenced by DeleteLastWagon().

static void UpdateSignalsAroundSegment | ( | SigFlags | flags | ) | `[static]`

Update signals around segment in _tbuset.

Parameters:

  | flags | info about segment

Definition at line 409 of file signal.cpp.

References _globset, _tbuset, GetSignalStateByTrackdir(), HasSignalOnTrackdir(), MarkTileDirtyByTile(), ReverseTrackdir(), SetSignalStateByTrackdir(), SF_EXIT, SF_EXIT2, SF_GREEN, SF_GREEN2, SF_TRAIN, SIGNAL_STATE_GREEN, SIGNAL_STATE_RED, SIGTYPE_COMBO, TrackdirToExitdir(), and TrackdirToTrack().

Referenced by UpdateSignalsInBuffer().

static SigSegState UpdateSignalsInBuffer | ( | Owner | owner | ) | `[static]`

Updates blocks in _globset buffer.

Parameters:

  | owner | company whose signals we are updating

Returns:
  state of the first block from _globset

Precondition:
  IsValidCompanyID(owner)

Definition at line 471 of file signal.cpp.

References _globset, _tbdset, _tbuset, ExploreSegment(), GetOtherTunnelBridgeEnd(), GetRailDepotDirection(), GetTileTrackStatus(), GetTileType(), GetTunnelBridgeDirection(), GetTunnelBridgeTransportType(), INVALID_DIAGDIR, IsRailDepot(), MP_RAILWAY, MP_ROAD, MP_STATION, MP_TUNNELBRIDGE, ResetSets(), ReverseDiagDir(), SF_EXIT, SF_FULL, SF_GREEN, SF_PBS, SF_TRAIN, SIGSEG_FREE, SIGSEG_FULL, SIGSEG_PBS, TileOffsByDiagDir(), TRACK_BIT_NONE, TrackStatusToTrackBits(), TRANSPORT_RAIL, and UpdateSignalsAroundSegment().

Referenced by AddSideToSignalBuffer(), AddTrackToSignalBuffer(), DoCommandP(), DoFloodTile(), SetSignalsOnBothDir(), UpdateSignalsInBuffer(), and UpdateSignalsOnSegment().

SigSegState UpdateSignalsOnSegment | ( | TileIndex | tile,
|  | DiagDirection | side,
|  | Owner | owner |
| ) |  |  |

Update signals, starting at one side of a tile Will check tile next to this at opposite side too.

See also:
  UpdateSignalsInBuffer()

Parameters:

  | tile | tile where we start
  | side | side of tile
  | owner | owner whose signals we will update

Returns:
  the state of the signal segment

Definition at line 637 of file signal.cpp.

References _globset, and UpdateSignalsInBuffer().

Referenced by DeleteLastWagon().

## Variable Documentation

const TrackBitsByte _enterdir_to_trackbits[DIAGDIR_END]`[static]`

Initial value:

     {
      {TRACK_BIT_3WAY_NE},
      {TRACK_BIT_3WAY_SE},
      {TRACK_BIT_3WAY_SW},
      {TRACK_BIT_3WAY_NW}
    }

incidating trackbits with given enterdir

Definition at line 26 of file signal.cpp.

const TrackdirBitsShort _enterdir_to_trackdirbits[DIAGDIR_END]`[static]`

Initial value:

     {
      {TRACKDIR_BIT_X_SW | TRACKDIR_BIT_UPPER_W | TRACKDIR_BIT_RIGHT_S},
      {TRACKDIR_BIT_Y_NW | TRACKDIR_BIT_LOWER_W | TRACKDIR_BIT_RIGHT_N},
      {TRACKDIR_BIT_X_NE | TRACKDIR_BIT_LOWER_E | TRACKDIR_BIT_LEFT_N},
      {TRACKDIR_BIT_Y_SE | TRACKDIR_BIT_UPPER_E | TRACKDIR_BIT_LEFT_S}
    }

incidating trackdirbits with given enterdir

Definition at line 34 of file signal.cpp.