OpenTTD-patches/src/pbs.cpp
2023-05-06 16:19:52 +01:00

1576 lines
61 KiB
C++

/*
* This file is part of OpenTTD.
* OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
* OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
*/
/** @file pbs.cpp PBS support routines */
#include "stdafx.h"
#include "viewport_func.h"
#include "vehicle_func.h"
#include "newgrf_station.h"
#include "pathfinder/follow_track.hpp"
#include "tracerestrict.h"
#include "newgrf_newsignals.h"
#include "safeguards.h"
/**
* Get the reserved trackbits for any tile, regardless of type.
* @param t the tile
* @return the reserved trackbits. TRACK_BIT_NONE on nothing reserved or
* a tile without rail.
*/
TrackBits GetReservedTrackbits(TileIndex t)
{
switch (GetTileType(t)) {
case MP_RAILWAY:
if (IsRailDepot(t)) return GetDepotReservationTrackBits(t);
if (IsPlainRail(t)) return GetRailReservationTrackBits(t);
break;
case MP_ROAD:
if (IsLevelCrossing(t)) return GetCrossingReservationTrackBits(t);
break;
case MP_STATION:
if (HasStationRail(t)) return GetStationReservationTrackBits(t);
break;
case MP_TUNNELBRIDGE:
if (GetTunnelBridgeTransportType(t) == TRANSPORT_RAIL) return GetTunnelBridgeReservationTrackBits(t);
break;
default:
break;
}
return TRACK_BIT_NONE;
}
/**
* Set the reservation for a complete station platform.
* @pre IsRailStationTile(start)
* @param start starting tile of the platform
* @param dir the direction in which to follow the platform
* @param b the state the reservation should be set to
*/
void SetRailStationPlatformReservation(TileIndex start, DiagDirection dir, bool b)
{
TileIndex tile = start;
TileIndexDiff diff = TileOffsByDiagDir(dir);
assert_tile(IsRailStationTile(start), start);
assert_tile(GetRailStationAxis(start) == DiagDirToAxis(dir), start);
do {
SetRailStationReservation(tile, b);
MarkTileDirtyByTile(tile, VMDF_NOT_MAP_MODE);
tile = TILE_ADD(tile, diff);
} while (IsCompatibleTrainStationTile(tile, start));
}
/**
* Try to reserve a specific track on a tile
* This also sets PBS signals to green if reserving through the facing track direction
* @param v the train performing the reservation
* @param tile the tile
* @param t the track
* @param trigger_stations whether to call station randomisation trigger
* @return \c true if reservation was successful, i.e. the track was
* free and didn't cross any other reserved tracks.
*/
bool TryReserveRailTrackdir(const Train *v, TileIndex tile, Trackdir td, bool trigger_stations)
{
bool success = TryReserveRailTrack(tile, TrackdirToTrack(td), trigger_stations);
if (success && HasPbsSignalOnTrackdir(tile, td)) {
SetSignalStateByTrackdir(tile, td, SIGNAL_STATE_GREEN);
MarkSingleSignalDirty(tile, td);
if (_extra_aspects > 0) {
SetSignalAspect(tile, TrackdirToTrack(td), 0);
UpdateAspectDeferredWithVehicle(v, tile, td, true);
}
}
return success;
}
/**
* Try to reserve a specific track on a tile
* @param tile the tile
* @param track the track
* @param trigger_stations whether to call station randomisation trigger
* @return \c true if reservation was successful, i.e. the track was
* free and didn't cross any other reserved tracks.
*/
bool TryReserveRailTrack(TileIndex tile, Track track, bool trigger_stations)
{
assert_msg_tile((TrackdirBitsToTrackBits(GetTileTrackdirBits(tile, TRANSPORT_RAIL, 0)) & TrackToTrackBits(track)) != 0, tile,
"%X, %X, %X", TrackdirBitsToTrackBits(GetTileTrackdirBits(tile, TRANSPORT_RAIL, 0)), track, TrackToTrackBits(track));
if (_settings_client.gui.show_track_reservation) {
/* show the reserved rail if needed */
if (IsTileType(tile, MP_TUNNELBRIDGE)) {
MarkBridgeOrTunnelDirtyOnReservationChange(tile, VMDF_NOT_MAP_MODE);
} else {
MarkTileGroundDirtyByTile(tile, VMDF_NOT_MAP_MODE);
}
}
switch (GetTileType(tile)) {
case MP_RAILWAY:
if (IsPlainRail(tile)) return TryReserveTrack(tile, track);
if (IsRailDepot(tile)) {
if (!HasDepotReservation(tile)) {
SetDepotReservation(tile, true);
MarkTileDirtyByTile(tile, VMDF_NOT_MAP_MODE); // some GRFs change their appearance when tile is reserved
return true;
}
}
break;
case MP_ROAD:
if (IsLevelCrossing(tile) && !HasCrossingReservation(tile)) {
if (_settings_game.vehicle.safer_crossings) {
if (IsCrossingOccupiedByRoadVehicle(tile)) return false;
if (_settings_game.vehicle.adjacent_crossings) {
const Axis axis = GetCrossingRoadAxis(tile);
for (TileIndex t = tile; t < MapSize() && IsLevelCrossingTile(t) && GetCrossingRoadAxis(t) == axis; t = TileAddByDiagDir(t, AxisToDiagDir(GetCrossingRoadAxis(t)))) {
if (IsCrossingOccupiedByRoadVehicle(t)) return false;
}
for (TileIndex t = tile; t < MapSize() && IsLevelCrossingTile(t) && GetCrossingRoadAxis(t) == axis; t = TileAddByDiagDir(t, ReverseDiagDir(AxisToDiagDir(GetCrossingRoadAxis(t))))) {
if (IsCrossingOccupiedByRoadVehicle(t)) return false;
}
}
}
SetCrossingReservation(tile, true);
UpdateLevelCrossing(tile, false);
return true;
}
break;
case MP_STATION:
if (HasStationRail(tile) && !HasStationReservation(tile)) {
SetRailStationReservation(tile, true);
if (trigger_stations && IsRailStation(tile)) TriggerStationRandomisation(nullptr, tile, SRT_PATH_RESERVATION);
MarkTileDirtyByTile(tile, VMDF_NOT_MAP_MODE); // some GRFs need redraw after reserving track
return true;
}
break;
case MP_TUNNELBRIDGE:
if (GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) {
if (IsTunnel(tile) && !HasTunnelReservation(tile)) {
SetTunnelReservation(tile, true);
MarkTileGroundDirtyByTile(tile, VMDF_NOT_MAP_MODE);
return true;
}
if (IsBridge(tile)) {
if (TryReserveRailBridgeHead(tile, track)) {
MarkBridgeOrTunnelDirtyOnReservationChange(tile, VMDF_NOT_MAP_MODE);
return true;
}
}
}
break;
default:
break;
}
return false;
}
/**
* Lift the reservation of a specific trackdir on a tile
* This also sets PBS signals to red if unreserving through the facing track direction
* @param tile the tile
* @param t the track
*/
void UnreserveRailTrackdir(TileIndex tile, Trackdir td)
{
if (HasPbsSignalOnTrackdir(tile, td)) {
SetSignalStateByTrackdir(tile, td, SIGNAL_STATE_RED);
MarkSingleSignalDirty(tile, td);
}
UnreserveRailTrack(tile, TrackdirToTrack(td));
}
/**
* Lift the reservation of a specific track on a tile
* @param tile the tile
* @param t the track
*/
void UnreserveRailTrack(TileIndex tile, Track t)
{
assert_msg_tile(TrackdirBitsToTrackBits(GetTileTrackdirBits(tile, TRANSPORT_RAIL, 0)) & TrackToTrackBits(t), tile, "track: %u", t);
if (_settings_client.gui.show_track_reservation) {
if (IsTileType(tile, MP_TUNNELBRIDGE)) {
MarkBridgeOrTunnelDirtyOnReservationChange(tile, VMDF_NOT_MAP_MODE);
} else {
MarkTileGroundDirtyByTile(tile, VMDF_NOT_MAP_MODE);
}
}
switch (GetTileType(tile)) {
case MP_RAILWAY:
if (IsRailDepot(tile)) {
SetDepotReservation(tile, false);
MarkTileDirtyByTile(tile, VMDF_NOT_MAP_MODE);
break;
}
if (IsPlainRail(tile)) UnreserveTrack(tile, t);
break;
case MP_ROAD:
if (IsLevelCrossing(tile)) {
SetCrossingReservation(tile, false);
UpdateLevelCrossing(tile);
}
break;
case MP_STATION:
if (HasStationRail(tile)) {
SetRailStationReservation(tile, false);
MarkTileDirtyByTile(tile, VMDF_NOT_MAP_MODE);
}
break;
case MP_TUNNELBRIDGE:
if (GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) {
if (IsTunnel(tile)) {
SetTunnelReservation(tile, false);
} else {
UnreserveRailBridgeHeadTrack(tile, t);
}
if (IsTunnelBridgeSignalSimulationExit(tile) && IsTunnelBridgeEffectivelyPBS(tile) && IsTrackAcrossTunnelBridge(tile, t)) {
if (IsTunnelBridgePBS(tile)) {
SetTunnelBridgeExitSignalState(tile, SIGNAL_STATE_RED);
if (_extra_aspects > 0) PropagateAspectChange(tile, GetTunnelBridgeExitTrackdir(tile), 0);
} else {
UpdateSignalsOnSegment(tile, INVALID_DIAGDIR, GetTileOwner(tile));
}
}
MarkBridgeOrTunnelDirtyOnReservationChange(tile, VMDF_NOT_MAP_MODE);
}
break;
default:
break;
}
}
/** Flags for FollowReservation */
enum FollowReservationFlags {
FRF_NONE = 0, ///< No flags
FRF_IGNORE_ONEWAY = 0x01, ///< Ignore one way signals in the opposite direction
FRF_TB_EXIT_FREE = 0x02, ///< Exit of starting tunnel/bridge is free
};
DECLARE_ENUM_AS_BIT_SET(FollowReservationFlags)
static void CheckCurveLookAhead(const Train *v, TrainReservationLookAhead *lookahead, int end_position, int z, RailType rt)
{
/* Coarse filter: remove curves beyond train length */
while (!lookahead->curves.empty() && lookahead->curves.front().position < end_position - v->gcache.cached_total_length) {
lookahead->curves.pop_front();
}
if (lookahead->curves.empty() || v->Next() == nullptr) return;
static const int absolute_max_speed = UINT16_MAX;
int max_speed = absolute_max_speed;
int curvecount[2] = {0, 0};
/* first find the curve speed limit */
int numcurve = 0;
int sum = 0;
int pos = 0;
int lastpos = -1;
const Train *u = v->Next();
int veh_offset = v->CalcNextVehicleOffset();
for (auto iter = lookahead->curves.rbegin(); iter != lookahead->curves.rend(); ++iter) {
const TrainReservationLookAheadCurve &curve = *iter;
int delta = end_position - curve.position;
while (delta >= veh_offset) {
if (u->Next() != nullptr) {
veh_offset += u->CalcNextVehicleOffset();
u = u->Next();
pos++;
} else {
u = nullptr;
break;
}
}
if (u == nullptr) break;
if (curve.dir_diff == DIRDIFF_45LEFT) curvecount[0]++;
if (curve.dir_diff == DIRDIFF_45RIGHT) curvecount[1]++;
if (curve.dir_diff == DIRDIFF_45LEFT || curve.dir_diff == DIRDIFF_45RIGHT) {
if (lastpos != -1) {
numcurve++;
sum += pos - lastpos;
if (pos - lastpos == 1 && max_speed > 88) {
max_speed = 88;
}
}
lastpos = pos;
}
/* if we have a 90 degree turn, fix the speed limit to 60 */
if (curve.dir_diff == DIRDIFF_90LEFT || curve.dir_diff == DIRDIFF_90RIGHT) {
max_speed = 61;
}
}
if (numcurve > 0 && max_speed > 88) {
if (curvecount[0] == 1 && curvecount[1] == 1) {
max_speed = absolute_max_speed;
} else {
sum /= numcurve;
max_speed = 232 - (13 - Clamp(sum, 1, 12)) * (13 - Clamp(sum, 1, 12));
}
}
if (max_speed != absolute_max_speed) {
/* Apply the engine's rail type curve speed advantage, if it slowed by curves */
const RailtypeInfo *rti = GetRailTypeInfo(rt);
max_speed += (max_speed / 2) * rti->curve_speed;
if (v->tcache.cached_tflags & TCF_TILT) {
/* Apply max_speed bonus of 20% for a tilting train */
max_speed += max_speed / 5;
}
lookahead->AddCurveSpeedLimit(max_speed, 4, z);
}
}
static int LookaheadTileHeightForChunnel(int length, int offset)
{
if (offset == 0) return 0;
if (offset < 3) return -1 * (int)TILE_HEIGHT;
if (offset < length - 3) return -2 * (int)TILE_HEIGHT;
if (offset < length) return -1 * (int)TILE_HEIGHT;
return 0;
}
static uint16 ApplyTunnelBridgeLookaheadSignalSpeedRestriction(TileIndex tile, Trackdir trackdir, const Train *v,
uint16 initial_speed_restriction, TrainReservationLookAhead *lookahead, int offset, int16 z)
{
uint16 speed_restriction = initial_speed_restriction;
if (v != nullptr && IsTunnelBridgeRestrictedSignal(tile)) {
if (trackdir == INVALID_TRACKDIR) {
trackdir = GetTunnelBridgeExitTrackdir(tile);
}
const TraceRestrictProgram *prog = GetExistingTraceRestrictProgram(tile, TrackdirToTrack(trackdir));
if (prog && prog->actions_used_flags & TRPAUF_SPEED_RESTRICTION) {
TraceRestrictProgramResult out;
TraceRestrictProgramInput input(tile, trackdir, nullptr, nullptr);
prog->Execute(v, input, out);
if (out.flags & TRPRF_SPEED_RESTRICTION_SET) {
int duration;
if (TrackdirEntersTunnelBridge(tile, trackdir)) {
duration = 4 + (IsDiagonalTrackdir(trackdir) ? 16 : 8);
} else {
duration = 4;
}
lookahead->AddSpeedRestriction(out.speed_restriction, offset, duration, z);
if (out.speed_restriction != 0 && (speed_restriction == 0 || out.speed_restriction < speed_restriction)) {
/* lower of the speed restrictions before or after the signal */
speed_restriction = out.speed_restriction;
}
}
}
}
return speed_restriction;
}
static uint16 GetTrainSpeedLimitForRailtype(const Train *v, RailType rt, TileIndex tile, Track track)
{
uint16 speed = GetRailTypeInfo(rt)->max_speed;
if (v->tcache.cached_tflags & TCF_SPD_RAILTYPE) {
for (const Train *u = v; u != nullptr; u = u->Next()) {
if (u->GetEngine()->callbacks_used & SGCU_CB36_SPEED_RAILTYPE) {
const TileIndex prev_tile = u->tile;
const TrackBits prev_track = u->track;
const_cast<Train *>(u)->tile = tile;
const_cast<Train *>(u)->track = TrackToTrackBits(track);
uint16 cb_speed = GetVehicleProperty(u, PROP_TRAIN_SPEED, speed);
if (cb_speed != 0 && (cb_speed < speed || speed == 0)) speed = cb_speed;
const_cast<Train *>(u)->tile = prev_tile;
const_cast<Train *>(u)->track = prev_track;
}
}
}
return speed;
}
/** Follow a reservation starting from a specific tile to the end. */
static PBSTileInfo FollowReservation(Owner o, RailTypes rts, TileIndex tile, Trackdir trackdir, FollowReservationFlags flags, const Train *v, TrainReservationLookAhead *lookahead)
{
TileIndex start_tile = tile;
Trackdir start_trackdir = trackdir;
bool first_loop = true;
/* Start track not reserved? This can happen if two trains
* are on the same tile. The reservation on the next tile
* is not ours in this case, so exit. */
if (!(flags & FRF_TB_EXIT_FREE) && !HasReservedTracks(tile, TrackToTrackBits(TrackdirToTrack(trackdir)))) return PBSTileInfo(tile, trackdir, false);
RailType rt = INVALID_RAILTYPE;
Direction dir = INVALID_DIR;
int z = 0;
auto update_z = [&](TileIndex t, Trackdir td, bool force) {
if (force || TrackdirToTrack(td) == TRACK_X || TrackdirToTrack(td) == TRACK_Y) {
if (IsBridgeTile(t) && TrackdirToExitdir(td) == GetTunnelBridgeDirection(t)) {
z = GetBridgePixelHeight(t);
} else {
int x = (TileX(t) * TILE_SIZE) + 8;
int y = (TileY(t) * TILE_SIZE) + 8;
if (!IsTunnelTile(tile)) {
switch (TrackdirToExitdir(td)) {
case DIAGDIR_NE: x -= 8; break;
case DIAGDIR_SE: y += 7; break;
case DIAGDIR_SW: x += 7; break;
case DIAGDIR_NW: y -= 8; break;
default: NOT_REACHED();
}
}
z = GetSlopePixelZ(x, y, true);
}
}
};
if (lookahead != nullptr) {
rt = GetRailTypeByTrack(tile, TrackdirToTrack(trackdir));
dir = TrackdirToDirection(trackdir);
update_z(tile, trackdir, true);
}
auto check_rail_type = [&](TileIndex t, Trackdir td, int offset) {
RailType new_rt = GetRailTypeByTrack(t, TrackdirToTrack(td));
if (new_rt != rt) {
uint16 rail_speed = GetTrainSpeedLimitForRailtype(v, new_rt, t, TrackdirToTrack(td));
if (rail_speed > 0) lookahead->AddTrackSpeedLimit(rail_speed, offset, 4, z);
if (GetRailTypeInfo(rt)->curve_speed != GetRailTypeInfo(new_rt)->curve_speed) {
CheckCurveLookAhead(v, lookahead, lookahead->RealEndPosition() + 4 + offset, z, new_rt);
}
rt = new_rt;
}
};
auto check_direction = [&](Direction new_dir, int offset, TileIndex tile) {
if (dir == new_dir) return;
DirDiff dirdiff = DirDifference(dir, new_dir);
int end = lookahead->RealEndPosition() + 4;
lookahead->curves.push_back({ end + offset, dirdiff });
dir = new_dir;
CheckCurveLookAhead(v, lookahead, end + offset, z, rt);
};
/* Do not disallow 90 deg turns as the setting might have changed between reserving and now. */
CFollowTrackRail ft(o, rts);
auto check_tunnel_bridge = [&]() -> bool {
if (IsTunnelBridgeWithSignalSimulation(tile) && TrackdirEntersTunnelBridge(tile, trackdir)) {
if (_settings_game.vehicle.train_braking_model == TBM_REALISTIC && IsTunnelBridgeSignalSimulationEntrance(tile)) {
TileIndex end = GetOtherTunnelBridgeEnd(tile);
if (HasAcrossTunnelBridgeReservation(end) && GetTunnelBridgeExitSignalState(end) == SIGNAL_STATE_GREEN &&
((flags & FRF_TB_EXIT_FREE) || TunnelBridgeIsFree(tile, end, nullptr, TBIFM_ACROSS_ONLY).Succeeded())) {
/* skip far end */
if (lookahead != nullptr) {
lookahead->reservation_end_position += (DistanceManhattan(tile, end) - 1) * TILE_SIZE;
}
Trackdir end_trackdir = GetTunnelBridgeExitTrackdir(end);
if (lookahead != nullptr) {
if ((flags & FRF_TB_EXIT_FREE) && GetTunnelBridgeLength(tile, end) > 1) {
/* middle part of bridge is in wormhole direction */
dir = DiagDirToDir(GetTunnelBridgeDirection(tile));
}
check_direction(TrackdirToDirection(end_trackdir), 0, end);
lookahead->reservation_end_position += (IsDiagonalTrackdir(end_trackdir) ? 16 : 8);
update_z(end, end_trackdir, false);
}
tile = end;
trackdir = end_trackdir;
return true;
}
}
if ((flags & FRF_IGNORE_ONEWAY) && _settings_game.vehicle.train_braking_model == TBM_REALISTIC && IsTunnelBridgeSignalSimulationExit(tile) &&
GetTunnelBridgeExitSignalState(tile) == SIGNAL_STATE_GREEN) {
TileIndex end = GetOtherTunnelBridgeEnd(tile);
if (HasAcrossTunnelBridgeReservation(end) && TunnelBridgeIsFree(tile, end, nullptr, TBIFM_ACROSS_ONLY).Succeeded()) {
/* skip far end */
tile = end;
trackdir = GetTunnelBridgeExitTrackdir(tile);
return true;
}
}
return false;
}
return true;
};
while (check_tunnel_bridge() && ft.Follow(tile, trackdir)) {
flags &= ~FRF_TB_EXIT_FREE;
TrackdirBits reserved = ft.m_new_td_bits & TrackBitsToTrackdirBits(GetReservedTrackbits(ft.m_new_tile));
/* No reservation --> path end found */
if (reserved == TRACKDIR_BIT_NONE) {
if (ft.m_is_station) {
/* Check skipped station tiles as well, maybe our reservation ends inside the station. */
TileIndexDiff diff = TileOffsByDiagDir(ft.m_exitdir);
while (ft.m_tiles_skipped-- > 0) {
ft.m_new_tile -= diff;
if (HasStationReservation(ft.m_new_tile)) {
if (lookahead != nullptr) {
lookahead->AddStation(1 + ft.m_tiles_skipped, GetStationIndex(ft.m_new_tile), z);
lookahead->reservation_end_position += (1 + ft.m_tiles_skipped) * TILE_SIZE;
}
tile = ft.m_new_tile;
trackdir = DiagDirToDiagTrackdir(ft.m_exitdir);
break;
}
}
}
break;
}
/* Can't have more than one reserved trackdir */
Trackdir new_trackdir = FindFirstTrackdir(reserved);
/* One-way signal against us. The reservation can't be ours as it is not
* a safe position from our direction and we can never pass the signal. */
if (!(flags & FRF_IGNORE_ONEWAY) && HasOnewaySignalBlockingTrackdir(ft.m_new_tile, new_trackdir)) break;
tile = ft.m_new_tile;
trackdir = new_trackdir;
if (lookahead != nullptr) {
if (ft.m_tiles_skipped > 0) {
DiagDirection skip_dir = ReverseDiagDir(TrackdirToExitdir(ReverseTrackdir(trackdir)));
check_direction(DiagDirToDir(skip_dir), 0, tile);
}
if (ft.m_is_station) {
if (ft.m_tiles_skipped > 0) {
TileIndexDiff diff = TileOffsByDiagDir(TrackdirToExitdir(trackdir));
TileIndex start = tile - (diff * ft.m_tiles_skipped);
for (int i = 0; i < ft.m_tiles_skipped; i++) {
check_rail_type(start, trackdir, i * TILE_SIZE);
start += diff;
}
}
check_rail_type(tile, trackdir, ft.m_tiles_skipped * TILE_SIZE);
lookahead->AddStation(1 + ft.m_tiles_skipped, GetStationIndex(ft.m_new_tile), z);
} else {
check_rail_type(tile, trackdir, 0);
}
check_direction(TrackdirToDirection(trackdir), ft.m_tiles_skipped * TILE_SIZE, tile);
if (IsTileType(tile, MP_TUNNELBRIDGE) && TrackdirEntersTunnelBridge(tile, trackdir)) {
uint16 bridge_speed = 0;
if (IsBridge(tile)) {
bridge_speed = GetBridgeSpec(GetBridgeType(tile))->speed;
lookahead->AddTrackSpeedLimit(bridge_speed, 0, 8, z);
}
const int start_offset = (IsDiagonalTrackdir(trackdir) ? 16 : 8);
const TileIndex end = GetOtherTunnelBridgeEnd(tile);
const int length = GetTunnelBridgeLength(tile, end);
if (IsTunnelBridgeSignalSimulationEntrance(tile)) {
const int spacing = GetTunnelBridgeSignalSimulationSpacing(tile);
const int signals = length / spacing;
uint16 speed_restriction = ApplyTunnelBridgeLookaheadSignalSpeedRestriction(tile, trackdir, v, lookahead->speed_restriction, lookahead, 0, z);
uint16 signal_speed = GetRailTypeInfo(rt)->max_speed;
if (signal_speed == 0 || (speed_restriction != 0 && speed_restriction < signal_speed)) signal_speed = speed_restriction;
if (signal_speed == 0 || (bridge_speed != 0 && bridge_speed < signal_speed)) signal_speed = bridge_speed;
const uint16 signal_flags = GetTunnelBridgeSignalStyle(tile) << 8;
/* Entrance signal */
lookahead->AddSignal(signal_speed, 0, z, signal_flags);
update_z(tile, trackdir, false);
if (length > 1) {
check_direction(DiagDirToDir(GetTunnelBridgeDirection(tile)), start_offset, tile);
}
bool chunnel = IsTunnel(tile) && Tunnel::GetByTile(tile)->is_chunnel;
/* Middle signals */
int offset = start_offset - TILE_SIZE;
for (int i = 0; i < signals; i++) {
offset += TILE_SIZE * spacing;
lookahead->AddSignal(signal_speed, offset, chunnel ? LookaheadTileHeightForChunnel(length, i * spacing) : z, signal_flags);
}
/* Exit signal */
const int end_offset = start_offset + (TILE_SIZE * length);
uint16 exit_speed_restriction = ApplyTunnelBridgeLookaheadSignalSpeedRestriction(end, INVALID_TRACKDIR, v, lookahead->speed_restriction, lookahead, end_offset, z);
if (exit_speed_restriction != speed_restriction) {
speed_restriction = exit_speed_restriction;
signal_speed = GetRailTypeInfo(rt)->max_speed;
if (signal_speed == 0 || (speed_restriction != 0 && speed_restriction < signal_speed)) signal_speed = speed_restriction;
if (signal_speed == 0 || (bridge_speed != 0 && bridge_speed < signal_speed)) signal_speed = bridge_speed;
}
lookahead->AddSignal(signal_speed, end_offset, z, signal_flags);
lookahead->SetNextExtendPositionIfUnset();
} else {
update_z(tile, trackdir, false);
if (length > 1) {
check_direction(DiagDirToDir(GetTunnelBridgeDirection(tile)), start_offset, tile);
}
}
}
if (IsTileType(tile, MP_RAILWAY) && HasSignalOnTrack(tile, TrackdirToTrack(trackdir))) {
TraceRestrictProgramActionsUsedFlags au_flags;
if (HasSignalOnTrackdir(tile, trackdir)) {
/* Passing through a signal from the front side */
au_flags = TRPAUF_SPEED_RESTRICTION;
} else {
/* Passing through a signal from the rear side */
au_flags = TRPAUF_SPEED_RESTRICTION | TRPAUF_REVERSE;
}
uint16 speed_restriction = lookahead->speed_restriction;
if (v != nullptr) {
const TraceRestrictProgram *prog = GetExistingTraceRestrictProgram(tile, TrackdirToTrack(trackdir));
if (prog && prog->actions_used_flags & au_flags) {
TraceRestrictProgramResult out;
TraceRestrictProgramInput input(tile, trackdir, nullptr, nullptr);
prog->Execute(v, input, out);
if (out.flags & TRPRF_REVERSE && au_flags & TRPAUF_REVERSE) {
lookahead->AddReverse(z);
}
if (out.flags & TRPRF_SPEED_RESTRICTION_SET) {
lookahead->AddSpeedRestriction(out.speed_restriction, 0, 0, z);
if (out.speed_restriction != 0 && (speed_restriction == 0 || out.speed_restriction < speed_restriction)) {
/* lower of the speed restrictions before or after the signal */
speed_restriction = out.speed_restriction;
}
}
}
}
if (!(au_flags & TRPAUF_REVERSE)) {
/* Passing through a signal from the front side */
uint16 signal_speed = GetRailTypeInfo(rt)->max_speed;
if (signal_speed == 0 || (speed_restriction != 0 && speed_restriction < signal_speed)) signal_speed = speed_restriction;
uint8 signal_style = GetSignalStyle(tile, TrackdirToTrack(trackdir));
uint16 signal_flags = signal_style << 8;
if (HasBit(_signal_style_masks.non_aspect_inc, signal_style)) {
SetBit(signal_flags, TRSLAI_NO_ASPECT_INC);
}
if (HasBit(_signal_style_masks.next_only, signal_style)) {
SetBit(signal_flags, TRSLAI_NEXT_ONLY);
}
if (HasBit(_signal_style_masks.combined_normal_shunt, signal_style)) {
SetBit(signal_flags, TRSLAI_COMBINED);
UpdateLookaheadCombinedNormalShuntSignalDeferred(tile, trackdir, lookahead->RealEndPosition());
}
lookahead->AddSignal(signal_speed, 0, z, signal_flags);
lookahead->SetNextExtendPositionIfUnset();
}
}
lookahead->reservation_end_position += (IsDiagonalTrackdir(trackdir) ? 16 : 8) + (ft.m_tiles_skipped * 16);
update_z(tile, trackdir, false);
}
if (first_loop) {
/* Update the start tile after we followed the track the first
* time. This is necessary because the track follower can skip
* tiles (in stations for example) which means that we might
* never visit our original starting tile again. */
start_tile = tile;
start_trackdir = trackdir;
first_loop = false;
} else {
/* Loop encountered? */
if (tile == start_tile && trackdir == start_trackdir) break;
}
/* Depot tile? Can't continue. */
if (IsRailDepotTile(tile)) {
if (lookahead != nullptr) SetBit(lookahead->flags, TRLF_DEPOT_END);
break;
}
/* Non-pbs signal? Reservation can't continue. */
if (IsTileType(tile, MP_RAILWAY) && HasSignalOnTrackdir(tile, trackdir) && !IsPbsSignal(GetSignalType(tile, TrackdirToTrack(trackdir)))) break;
}
if (lookahead != nullptr) lookahead->reservation_end_z = z;
return PBSTileInfo(tile, trackdir, false);
}
/** Follow a reservation starting from a specific tile to the end. */
template <typename T>
static void FollowReservationEnumerate(Owner o, RailTypes rts, TileIndex tile, Trackdir trackdir, FollowReservationFlags flags, T handler)
{
TileIndex start_tile = tile;
Trackdir start_trackdir = trackdir;
bool first_loop = true;
/* Start track not reserved? This can happen if two trains
* are on the same tile. The reservation on the next tile
* is not ours in this case, so exit. */
if (!(flags & FRF_TB_EXIT_FREE) && !HasReservedTracks(tile, TrackToTrackBits(TrackdirToTrack(trackdir)))) return;
if (handler(start_tile, start_trackdir)) return;
/* Do not disallow 90 deg turns as the setting might have changed between reserving and now. */
CFollowTrackRail ft(o, rts);
auto check_tunnel_bridge = [&]() -> bool {
if (IsTunnelBridgeWithSignalSimulation(tile) && TrackdirEntersTunnelBridge(tile, trackdir)) {
if (_settings_game.vehicle.train_braking_model == TBM_REALISTIC && IsTunnelBridgeSignalSimulationEntrance(tile)) {
TileIndex end = GetOtherTunnelBridgeEnd(tile);
if (HasAcrossTunnelBridgeReservation(end) && GetTunnelBridgeExitSignalState(end) == SIGNAL_STATE_GREEN &&
((flags & FRF_TB_EXIT_FREE) || TunnelBridgeIsFree(tile, end, nullptr, TBIFM_ACROSS_ONLY).Succeeded())) {
/* skip far end */
Trackdir end_trackdir = GetTunnelBridgeExitTrackdir(end);
tile = end;
trackdir = end_trackdir;
if (handler(tile, trackdir)) return false;
return true;
}
}
if ((flags & FRF_IGNORE_ONEWAY) && _settings_game.vehicle.train_braking_model == TBM_REALISTIC && IsTunnelBridgeSignalSimulationExit(tile) &&
GetTunnelBridgeExitSignalState(tile) == SIGNAL_STATE_GREEN) {
TileIndex end = GetOtherTunnelBridgeEnd(tile);
if (HasAcrossTunnelBridgeReservation(end) && TunnelBridgeIsFree(tile, end, nullptr, TBIFM_ACROSS_ONLY).Succeeded()) {
/* skip far end */
tile = end;
trackdir = GetTunnelBridgeExitTrackdir(tile);
if (handler(tile, trackdir)) return false;
return true;
}
}
return false;
}
return true;
};
while (check_tunnel_bridge() && ft.Follow(tile, trackdir)) {
flags &= ~FRF_TB_EXIT_FREE;
TrackdirBits reserved = ft.m_new_td_bits & TrackBitsToTrackdirBits(GetReservedTrackbits(ft.m_new_tile));
if (ft.m_is_station) {
/* Check skipped station tiles as well, maybe our reservation ends inside the station. */
TileIndexDiff diff = TileOffsByDiagDir(ft.m_exitdir);
TileIndex t = ft.m_new_tile - (ft.m_tiles_skipped * diff);
while (ft.m_tiles_skipped-- > 0) {
if (HasStationReservation(t)) {
if (handler(t, DiagDirToDiagTrackdir(ft.m_exitdir))) return;
} else {
break;
}
t += diff;
}
}
/* No reservation --> path end found */
if (reserved == TRACKDIR_BIT_NONE) {
break;
}
/* Can't have more than one reserved trackdir */
Trackdir new_trackdir = FindFirstTrackdir(reserved);
/* One-way signal against us. The reservation can't be ours as it is not
* a safe position from our direction and we can never pass the signal. */
if (!(flags & FRF_IGNORE_ONEWAY) && HasOnewaySignalBlockingTrackdir(ft.m_new_tile, new_trackdir)) break;
tile = ft.m_new_tile;
trackdir = new_trackdir;
if (handler(tile, trackdir)) return;
if (first_loop) {
/* Update the start tile after we followed the track the first
* time. This is necessary because the track follower can skip
* tiles (in stations for example) which means that we might
* never visit our original starting tile again. */
start_tile = tile;
start_trackdir = trackdir;
first_loop = false;
} else {
/* Loop encountered? */
if (tile == start_tile && trackdir == start_trackdir) break;
}
/* Depot tile? Can't continue. */
if (IsRailDepotTile(tile)) {
break;
}
/* Non-pbs signal? Reservation can't continue. */
if (IsTileType(tile, MP_RAILWAY) && HasSignalOnTrackdir(tile, trackdir) && !IsPbsSignal(GetSignalType(tile, TrackdirToTrack(trackdir)))) break;
}
}
/**
* Helper struct for finding the best matching vehicle on a specific track.
*/
struct FindTrainOnTrackInfo {
PBSTileInfo res; ///< Information about the track.
Train *best; ///< The currently "best" vehicle we have found.
/** Init the best location to nullptr always! */
FindTrainOnTrackInfo() : best(nullptr) {}
};
/** Callback for Has/FindVehicleOnPos to find a train on a specific track. */
static Vehicle *FindTrainOnTrackEnum(Vehicle *v, void *data)
{
FindTrainOnTrackInfo *info = (FindTrainOnTrackInfo *)data;
if ((v->vehstatus & VS_CRASHED)) return nullptr;
Train *t = Train::From(v);
if (t->track & TRACK_BIT_WORMHOLE) {
/* Do not find trains inside signalled bridge/tunnels.
* Trains on the ramp/entrance itself are found though.
*/
if (IsTileType(info->res.tile, MP_TUNNELBRIDGE) && IsTunnelBridgeWithSignalSimulation(info->res.tile) && info->res.tile != TileVirtXY(t->x_pos, t->y_pos)) {
return nullptr;
}
}
if (t->track & TRACK_BIT_WORMHOLE || HasBit((TrackBits)t->track, TrackdirToTrack(info->res.trackdir))) {
t = t->First();
/* ALWAYS return the lowest ID (anti-desync!) */
if (info->best == nullptr || t->index < info->best->index) info->best = t;
return t;
}
return nullptr;
}
void TrainReservationLookAhead::SetNextExtendPosition()
{
int32 threshold = this->current_position + 24;
for (const TrainReservationLookAheadItem &item : this->items) {
if (item.type == TRLIT_SIGNAL && item.start > threshold) {
this->next_extend_position = item.start - 24;
return;
}
}
this->next_extend_position = this->current_position;
}
bool ValidateLookAhead(const Train *v)
{
TileIndex tile = v->lookahead->reservation_end_tile;
Trackdir trackdir = v->lookahead->reservation_end_trackdir;
if (HasBit(v->lookahead->flags, TRLF_TB_EXIT_FREE)) {
if (!likely(IsRailTunnelBridgeTile(tile) && TrackdirEntersTunnelBridge(tile, trackdir))) {
return false;
}
}
if (HasBit(v->lookahead->flags, TRLF_DEPOT_END) && !IsRailDepotTile(tile)) return false;
TrackdirBits trackdirbits = GetTileTrackdirBits(tile, TRANSPORT_RAIL, 0);
if (!HasTrackdir(trackdirbits, trackdir)) return false;
return true;
}
/**
* Follow a train reservation to the last tile.
*
* @param v the vehicle
* @param train_on_res Is set to a train we might encounter
* @returns The last tile of the reservation or the current train tile if no reservation present.
*/
PBSTileInfo FollowTrainReservation(const Train *v, Vehicle **train_on_res, FollowTrainReservationFlags flags)
{
assert(v->type == VEH_TRAIN);
TileIndex tile;
Trackdir trackdir;
if (!(flags & FTRF_IGNORE_LOOKAHEAD) && _settings_game.vehicle.train_braking_model == TBM_REALISTIC && v->lookahead != nullptr) {
tile = v->lookahead->reservation_end_tile;
trackdir = v->lookahead->reservation_end_trackdir;
if (HasBit(v->lookahead->flags, TRLF_DEPOT_END)) return PBSTileInfo(tile, trackdir, false);
if (HasBit(v->lookahead->flags, TRLF_TB_EXIT_FREE)) {
TileIndex exit_tile = GetOtherTunnelBridgeEnd(tile);
if (IsTunnelBridgeSignalSimulationExit(exit_tile) && GetTunnelBridgeExitSignalState(exit_tile) == SIGNAL_STATE_GREEN && HasAcrossTunnelBridgeReservation(exit_tile)) {
tile = exit_tile;
trackdir = GetTunnelBridgeExitTrackdir(exit_tile);
}
}
} else {
tile = v->tile;
trackdir = v->GetVehicleTrackdir();
}
if (IsRailDepotTile(tile) && !GetDepotReservationTrackBits(tile)) return PBSTileInfo(tile, trackdir, false);
FindTrainOnTrackInfo ftoti;
ftoti.res = FollowReservation(v->owner, GetRailTypeInfo(v->railtype)->all_compatible_railtypes, tile, trackdir, FRF_NONE, v, nullptr);
ftoti.res.okay = (flags & FTRF_OKAY_UNUSED) ? false : IsSafeWaitingPosition(v, ftoti.res.tile, ftoti.res.trackdir, true, _settings_game.pf.forbid_90_deg);
if (train_on_res != nullptr) {
FindVehicleOnPos(ftoti.res.tile, VEH_TRAIN, &ftoti, FindTrainOnTrackEnum);
if (ftoti.best != nullptr) *train_on_res = ftoti.best->First();
if (*train_on_res == nullptr && IsRailStationTile(ftoti.res.tile)) {
/* The target tile is a rail station. The track follower
* has stopped on the last platform tile where we haven't
* found a train. Also check all previous platform tiles
* for a possible train. */
TileIndexDiff diff = TileOffsByDiagDir(TrackdirToExitdir(ReverseTrackdir(ftoti.res.trackdir)));
for (TileIndex st_tile = ftoti.res.tile + diff; *train_on_res == nullptr && IsCompatibleTrainStationTile(st_tile, ftoti.res.tile); st_tile += diff) {
FindVehicleOnPos(st_tile, VEH_TRAIN, &ftoti, FindTrainOnTrackEnum);
if (ftoti.best != nullptr) *train_on_res = ftoti.best->First();
}
}
if (*train_on_res == nullptr && IsTileType(ftoti.res.tile, MP_TUNNELBRIDGE) && IsTrackAcrossTunnelBridge(ftoti.res.tile, TrackdirToTrack(ftoti.res.trackdir)) && !IsTunnelBridgeWithSignalSimulation(ftoti.res.tile)) {
/* The target tile is a bridge/tunnel, also check the other end tile. */
FindVehicleOnPos(GetOtherTunnelBridgeEnd(ftoti.res.tile), VEH_TRAIN, &ftoti, FindTrainOnTrackEnum);
if (ftoti.best != nullptr) *train_on_res = ftoti.best->First();
}
}
return ftoti.res;
}
void ApplyAvailableFreeTunnelBridgeTiles(TrainReservationLookAhead *lookahead, int free_tiles, TileIndex tile, TileIndex end)
{
SB(lookahead->flags, TRLF_TB_EXIT_FREE, 1, free_tiles == INT_MAX ? 1 : 0);
if (free_tiles == INT_MAX) {
/* whole tunnel/bridge is empty */
if (unlikely(end == INVALID_TILE)) end = GetOtherTunnelBridgeEnd(tile);
free_tiles = DistanceManhattan(tile, end) - 1;
} else {
if (free_tiles > 0) {
int spacing = GetTunnelBridgeSignalSimulationSpacing(tile);
free_tiles = (((free_tiles - 1) / spacing) * spacing) - 1;
} else {
free_tiles = -1;
}
}
lookahead->reservation_end_position += ((free_tiles - lookahead->tunnel_bridge_reserved_tiles) * TILE_SIZE);
lookahead->tunnel_bridge_reserved_tiles = free_tiles;
if (HasBit(lookahead->flags, TRLF_CHUNNEL)) {
if (unlikely(end == INVALID_TILE)) end = GetOtherTunnelBridgeEnd(tile);
lookahead->reservation_end_z = LookaheadTileHeightForChunnel(GetTunnelBridgeLength(tile, end), free_tiles + 1);
}
}
void FillLookAheadCurveDataFromTrainPosition(Train *t)
{
TileIndex tile = TileVirtXY(t->x_pos, t->y_pos);
Direction dir = t->direction;
int32 current_pos = t->lookahead->reservation_end_position + 4 - ((dir & 1) ? 16 : 8);
for (Train *u = t->Next(); u != nullptr; u = u->Next()) {
TileIndex cur_tile = TileVirtXY(u->x_pos, u->y_pos);
if (cur_tile == tile) continue;
tile = cur_tile;
if (u->direction != dir) {
DirDiff dirdiff = DirDifference(u->direction, dir);
t->lookahead->curves.push_front({ current_pos, dirdiff });
dir = u->direction;
}
current_pos -= ((dir & 1) ? 16 : 8);
}
}
static int ScanTrainPositionForLookAheadStation(Train *t, TileIndex start_tile)
{
StationID prev = INVALID_STATION;
int offset = 0;
int start_offset_tiles = 0;
TileIndex cur_tile = start_tile;
for (const Train *u = t; u != nullptr; u = u->Next()) {
if (u != t) {
TileIndex u_tile = TileVirtXY(u->x_pos, u->y_pos);
if (u_tile != cur_tile) {
offset += (IsDiagonalTrackdir(u->GetVehicleTrackdir()) ? 16 : 8);
cur_tile = u_tile;
}
}
if (HasStationTileRail(u->tile)) {
StationID current = GetStationIndex(u->tile);
if (current != prev) {
/* Train is in a station, add that to the lookahead */
TileIndex tile = u->tile;
Trackdir trackdir = u->GetVehicleTrackdir();
RailType rt = GetRailTypeByTrack(tile, TrackdirToTrack(trackdir));
int z = GetTileMaxPixelZ(tile);
DiagDirection forward_dir = TrackdirToExitdir(trackdir);
TileIndexDiff diff = TileOffsByDiagDir(forward_dir);
uint forward_length = BaseStation::GetByTile(tile)->GetPlatformLength(tile, forward_dir);
uint reverse_length = BaseStation::GetByTile(tile)->GetPlatformLength(tile, ReverseDiagDir(forward_dir));
if (u == t) {
for (uint i = 1; i < forward_length; i++) {
/* Check for mid platform rail type change */
TileIndex new_tile = tile + (i * diff);
RailType new_rt = GetRailTypeByTrack(new_tile, TrackdirToTrack(trackdir));
if (new_rt != rt) {
uint16 rail_speed = GetTrainSpeedLimitForRailtype(t, new_rt, new_tile, TrackdirToTrack(trackdir));
if (rail_speed > 0) t->lookahead->AddTrackSpeedLimit(rail_speed, (i - 1) * TILE_SIZE, 4, z);
rt = new_rt;
}
}
start_offset_tiles = forward_length - 1;
}
t->lookahead->AddStation(forward_length - 1, current, z);
t->lookahead->items.back().start -= offset + (reverse_length * TILE_SIZE);
t->lookahead->items.back().end -= offset;
prev = current;
}
} else {
prev = INVALID_STATION;
}
if (!HasBit(u->flags, VRF_BEYOND_PLATFORM_END)) break;
}
return start_offset_tiles;
}
void TryCreateLookAheadForTrainInTunnelBridge(Train *t)
{
if (IsTunnelBridgeSignalSimulationExitOnly(t->tile)) return;
DiagDirection tb_dir = GetTunnelBridgeDirection(t->tile);
if (DirToDiagDirAlongAxis(t->direction, DiagDirToAxis(tb_dir)) == tb_dir) {
/* going in the right direction, allocate a new lookahead */
t->lookahead.reset(new TrainReservationLookAhead());
t->lookahead->reservation_end_tile = t->tile;
t->lookahead->reservation_end_trackdir = GetTunnelBridgeEntranceTrackdir(t->tile);
t->lookahead->reservation_end_z = t->z_pos;
t->lookahead->current_position = 0;
t->lookahead->next_extend_position = 0;
t->lookahead->tunnel_bridge_reserved_tiles = DistanceManhattan(t->tile, TileVirtXY(t->x_pos, t->y_pos));
t->lookahead->reservation_end_position = GetTileMarginInFrontOfTrain(t);
t->lookahead->flags = 0;
t->lookahead->speed_restriction = t->speed_restriction;
t->lookahead->cached_zpos = t->CalculateOverallZPos();
t->lookahead->zpos_refresh_remaining = t->GetZPosCacheUpdateInterval();
if (IsTunnel(t->tile) && Tunnel::GetByTile(t->tile)->is_chunnel) SetBit(t->lookahead->flags, TRLF_CHUNNEL);
if (IsTunnelBridgeSignalSimulationEntrance(t->tile)) {
const uint16 bridge_speed = IsBridge(t->tile) ? GetBridgeSpec(GetBridgeType(t->tile))->speed : 0;
const TileIndex end = GetOtherTunnelBridgeEnd(t->tile);
const int length = GetTunnelBridgeLength(t->tile, end);
const int spacing = GetTunnelBridgeSignalSimulationSpacing(t->tile);
const int signals = length / spacing;
const RailType rt = GetRailTypeByTrack(t->tile, TrackdirToTrack(t->lookahead->reservation_end_trackdir));
uint16 signal_speed = GetRailTypeInfo(rt)->max_speed;
if (signal_speed == 0 || (t->speed_restriction != 0 && t->speed_restriction < signal_speed)) signal_speed = t->speed_restriction;
if (signal_speed == 0 || (bridge_speed != 0 && bridge_speed < signal_speed)) signal_speed = bridge_speed;
int z = IsBridge(t->tile) ? GetBridgeHeight(t->tile) : GetTilePixelZ(t->tile);
const uint16 signal_flags = GetTunnelBridgeSignalStyle(t->tile) << 8;
/* Middle signals */
int offset = -(int)TILE_SIZE;
for (int i = 0; i < signals; i++) {
offset += TILE_SIZE * spacing;
t->lookahead->AddSignal(signal_speed, offset, HasBit(t->lookahead->flags, TRLF_CHUNNEL) ? LookaheadTileHeightForChunnel(length, i * spacing) : z, signal_flags);
}
/* Exit signal */
const int end_offset = TILE_SIZE * length;
uint16 exit_speed_restriction = ApplyTunnelBridgeLookaheadSignalSpeedRestriction(end, INVALID_TRACKDIR, t, t->speed_restriction, t->lookahead.get(), end_offset, z);
if (exit_speed_restriction != t->speed_restriction) {
signal_speed = GetRailTypeInfo(rt)->max_speed;
if (signal_speed == 0 || (exit_speed_restriction != 0 && exit_speed_restriction < signal_speed)) signal_speed = exit_speed_restriction;
if (signal_speed == 0 || (bridge_speed != 0 && bridge_speed < signal_speed)) signal_speed = bridge_speed;
}
t->lookahead->AddSignal(signal_speed, end_offset, z, signal_flags);
t->lookahead->SetNextExtendPositionIfUnset();
}
FillLookAheadCurveDataFromTrainPosition(t);
TileIndex end = GetOtherTunnelBridgeEnd(t->tile);
int raw_free_tiles = GetAvailableFreeTilesInSignalledTunnelBridgeWithStartOffset(t->tile, end, t->lookahead->tunnel_bridge_reserved_tiles + 1);
ApplyAvailableFreeTunnelBridgeTiles(t->lookahead.get(), raw_free_tiles, t->tile, end);
ScanTrainPositionForLookAheadStation(t, TileVirtXY(t->x_pos, t->y_pos));
}
}
void SetTrainReservationLookaheadEnd(Train *v)
{
if (_settings_game.vehicle.realistic_braking_aspect_limited != TRBALM_ON || _extra_aspects == 0) {
v->lookahead->lookahead_end_position = v->lookahead->reservation_end_position + 1;
return;
}
if (v->lookahead->lookahead_end_position > v->lookahead->reservation_end_position) return;
int32 threshold = v->lookahead->current_position + 24;
uint8 known_signals_ahead = 1;
bool allow_skip_no_aspect_inc = false;
if (v->IsInDepot()) {
known_signals_ahead = _extra_aspects + 1;
allow_skip_no_aspect_inc = true;
}
for (const TrainReservationLookAheadItem &item : v->lookahead->items) {
if (item.end >= v->lookahead->reservation_end_position) break;
if (item.type == TRLIT_SIGNAL) {
if (HasBit(item.data_aux, TRSLAI_COMBINED_SHUNT)) {
/* Combined normal/shunt in shunt mode */
allow_skip_no_aspect_inc = false;
if (item.start <= threshold) {
known_signals_ahead = 1;
continue;
} else {
if (item.start > v->lookahead->lookahead_end_position) v->lookahead->lookahead_end_position = item.start;
return;
}
}
if (item.start <= threshold) {
/* Signal is within visual range */
uint8 style = item.data_aux >> 8;
uint8 max_aspect = (style == 0) ? _extra_aspects : _new_signal_styles[style - 1].lookahead_extra_aspects;
if (!HasBit(item.data_aux, TRSLAI_NEXT_ONLY)) allow_skip_no_aspect_inc = true;
max_aspect += ((HasBit(item.data_aux, TRSLAI_NO_ASPECT_INC) && allow_skip_no_aspect_inc) ? 1 : 2);
if (max_aspect > known_signals_ahead) known_signals_ahead = max_aspect;
}
if (!HasBit(item.data_aux, TRSLAI_NO_ASPECT_INC) || !allow_skip_no_aspect_inc) {
known_signals_ahead--;
if (known_signals_ahead == 0) {
if (item.start > v->lookahead->lookahead_end_position) v->lookahead->lookahead_end_position = item.start;
return;
}
}
}
}
/* Didn't need to stop at a signal along the reservation */
if (v->lookahead->reservation_end_position >= v->lookahead->lookahead_end_position) {
v->lookahead->lookahead_end_position = v->lookahead->reservation_end_position;
if (known_signals_ahead > 1) v->lookahead->lookahead_end_position++;
}
}
void FillTrainReservationLookAhead(Train *v)
{
TileIndex tile;
Trackdir trackdir;
if (v->lookahead == nullptr && (v->track & TRACK_BIT_WORMHOLE)) {
TryCreateLookAheadForTrainInTunnelBridge(v);
if (v->lookahead == nullptr) return;
}
if (v->lookahead == nullptr) {
v->lookahead.reset(new TrainReservationLookAhead());
v->lookahead->current_position = 0;
v->lookahead->next_extend_position = 0;
/* Special case, if called from TrainController,
* v->tile, v->track and v->direction can be updated to the new tile,
* but v->x_pos and v->y_pos can still use the cordinates on the old tile,
* GetTileMarginInFrontOfTrain could erroneously return -5 if the old and
* new directions don't match. */
v->lookahead->reservation_end_position = std::max(GetTileMarginInFrontOfTrain(v), -4);
v->lookahead->tunnel_bridge_reserved_tiles = 0;
v->lookahead->flags = 0;
v->lookahead->speed_restriction = v->speed_restriction;
v->lookahead->cached_zpos = v->CalculateOverallZPos();
v->lookahead->zpos_refresh_remaining = v->GetZPosCacheUpdateInterval();
FillLookAheadCurveDataFromTrainPosition(v);
tile = v->tile;
trackdir = v->GetVehicleTrackdir();
TileIndex virt_tile = TileVirtXY(v->x_pos, v->y_pos);
if (tile != virt_tile) {
v->lookahead->reservation_end_position += (IsDiagonalDirection(v->direction) ? 16 : 8);
}
int station_offset_tiles = ScanTrainPositionForLookAheadStation(v, tile);
if (station_offset_tiles > 0) {
TileIndexDiff diff = TileOffsByDiagDir(TrackdirToExitdir(trackdir));
tile += station_offset_tiles * diff;
v->lookahead->reservation_end_position += station_offset_tiles * TILE_SIZE;
}
} else {
tile = v->lookahead->reservation_end_tile;
trackdir = v->lookahead->reservation_end_trackdir;
if (IsTunnelBridgeSignalSimulationEntranceTile(tile) && TrackdirEntersTunnelBridge(tile, trackdir)) {
TileIndex end = GetOtherTunnelBridgeEnd(tile);
int raw_free_tiles;
if (HasBit(v->lookahead->flags, TRLF_TB_EXIT_FREE)) {
raw_free_tiles = INT_MAX;
} else {
raw_free_tiles = GetAvailableFreeTilesInSignalledTunnelBridgeWithStartOffset(tile, end, v->lookahead->tunnel_bridge_reserved_tiles + 1);
ApplyAvailableFreeTunnelBridgeTiles(v->lookahead.get(), raw_free_tiles, tile, end);
}
if (!(HasAcrossTunnelBridgeReservation(end) && GetTunnelBridgeExitSignalState(end) == SIGNAL_STATE_GREEN && raw_free_tiles == INT_MAX)) {
/* do not attempt to follow through a signalled tunnel/bridge if it is not empty or the far end is not reserved */
FlushDeferredDetermineCombineNormalShuntMode(v);
SetTrainReservationLookaheadEnd(v);
return;
}
}
}
if (IsRailDepotTile(tile) && !GetDepotReservationTrackBits(tile)) {
FlushDeferredDetermineCombineNormalShuntMode(v);
SetTrainReservationLookaheadEnd(v);
return;
}
FollowReservationFlags flags = FRF_NONE;
if (HasBit(v->lookahead->flags, TRLF_TB_EXIT_FREE)) flags |= FRF_TB_EXIT_FREE;
PBSTileInfo res = FollowReservation(v->owner, GetRailTypeInfo(v->railtype)->all_compatible_railtypes, tile, trackdir, flags, v, v->lookahead.get());
if (IsTunnelBridgeWithSignalSimulation(res.tile) && TrackdirEntersTunnelBridge(res.tile, res.trackdir)) {
SB(v->lookahead->flags, TRLF_CHUNNEL, 1, (IsTunnel(res.tile) && Tunnel::GetByTile(res.tile)->is_chunnel) ? 1 : 0);
if (v->lookahead->current_position < v->lookahead->reservation_end_position - ((int)TILE_SIZE * (1 + v->lookahead->tunnel_bridge_reserved_tiles))) {
/* Vehicle is not itself in this tunnel/bridge, scan how much is available */
TileIndex end = INVALID_TILE;
int free_tiles;
if (GetTunnelBridgeEntranceSignalState(res.tile) == SIGNAL_STATE_GREEN) {
end = GetOtherTunnelBridgeEnd(res.tile);
free_tiles = GetAvailableFreeTilesInSignalledTunnelBridge(res.tile, end, res.tile);
} else {
free_tiles = -1;
}
ApplyAvailableFreeTunnelBridgeTiles(v->lookahead.get(), free_tiles, res.tile, end);
}
} else {
ClrBit(v->lookahead->flags, TRLF_TB_EXIT_FREE);
ClrBit(v->lookahead->flags, TRLF_CHUNNEL);
if (v->lookahead->tunnel_bridge_reserved_tiles != 0) {
v->lookahead->reservation_end_position -= (v->lookahead->tunnel_bridge_reserved_tiles * (int)TILE_SIZE);
v->lookahead->tunnel_bridge_reserved_tiles = 0;
}
}
v->lookahead->reservation_end_tile = res.tile;
v->lookahead->reservation_end_trackdir = res.trackdir;
FlushDeferredDetermineCombineNormalShuntMode(v);
SetTrainReservationLookaheadEnd(v);
}
/**
* Find the train which has reserved a specific path.
*
* @param tile A tile on the path.
* @param track A reserved track on the tile.
* @return The vehicle holding the reservation or nullptr if the path is stray.
*/
Train *GetTrainForReservation(TileIndex tile, Track track)
{
assert_msg_tile(HasReservedTracks(tile, TrackToTrackBits(track)), tile, "track: %u", track);
Trackdir trackdir = TrackToTrackdir(track);
RailTypes rts = GetRailTypeInfo(GetTileRailTypeByTrack(tile, track))->all_compatible_railtypes;
/* Follow the path from tile to both ends, one of the end tiles should
* have a train on it. We need FollowReservation to ignore one-way signals
* here, as one of the two search directions will be the "wrong" way. */
for (int i = 0; i < 2; ++i, trackdir = ReverseTrackdir(trackdir)) {
/* If the tile has a one-way block signal in the current trackdir, skip the
* search in this direction as the reservation can't come from this side.*/
if (HasOnewaySignalBlockingTrackdir(tile, ReverseTrackdir(trackdir)) && !HasPbsSignalOnTrackdir(tile, trackdir)) continue;
FindTrainOnTrackInfo ftoti;
ftoti.res = FollowReservation(GetTileOwner(tile), rts, tile, trackdir, FRF_IGNORE_ONEWAY, nullptr, nullptr);
FindVehicleOnPos(ftoti.res.tile, VEH_TRAIN, &ftoti, FindTrainOnTrackEnum);
if (ftoti.best != nullptr) return ftoti.best;
/* Special case for stations: check the whole platform for a vehicle. */
if (IsRailStationTile(ftoti.res.tile)) {
TileIndexDiff diff = TileOffsByDiagDir(TrackdirToExitdir(ReverseTrackdir(ftoti.res.trackdir)));
for (TileIndex st_tile = ftoti.res.tile + diff; IsCompatibleTrainStationTile(st_tile, ftoti.res.tile); st_tile += diff) {
FindVehicleOnPos(st_tile, VEH_TRAIN, &ftoti, FindTrainOnTrackEnum);
if (ftoti.best != nullptr) return ftoti.best;
}
}
if (IsTileType(ftoti.res.tile, MP_TUNNELBRIDGE) && IsTrackAcrossTunnelBridge(ftoti.res.tile, TrackdirToTrack(ftoti.res.trackdir))) {
if (IsTunnelBridgeWithSignalSimulation(ftoti.res.tile)) {
/* Special case for signalled bridges/tunnels: find best train on bridge/tunnel if exit reserved. */
if (IsTunnelBridgeSignalSimulationExit(ftoti.res.tile) && !(IsTunnelBridgeEffectivelyPBS(ftoti.res.tile) && GetTunnelBridgeExitSignalState(ftoti.res.tile) == SIGNAL_STATE_RED)) {
ftoti.best = GetTrainClosestToTunnelBridgeEnd(ftoti.res.tile, GetOtherTunnelBridgeEnd(ftoti.res.tile));
}
} else {
/* Special case for bridges/tunnels: check the other end as well. */
FindVehicleOnPos(GetOtherTunnelBridgeEnd(ftoti.res.tile), VEH_TRAIN, &ftoti, FindTrainOnTrackEnum);
}
if (ftoti.best != nullptr) return ftoti.best;
}
}
return nullptr;
}
CommandCost CheckTrainReservationPreventsTrackModification(TileIndex tile, Track track)
{
if (_settings_game.vehicle.train_braking_model == TBM_REALISTIC) {
return CheckTrainReservationPreventsTrackModification(GetTrainForReservation(tile, track));
}
return CommandCost();
}
CommandCost CheckTrainReservationPreventsTrackModification(const Train *v)
{
if (_settings_game.vehicle.train_braking_model == TBM_REALISTIC && v != nullptr && v->UsingRealisticBraking() && (v->cur_speed > 0 || !(v->vehstatus & (VS_STOPPED | VS_CRASHED)))) {
return_cmd_error(STR_ERROR_CANNOT_MODIFY_TRACK_TRAIN_APPROACHING);
}
return CommandCost();
}
static Vehicle *TrainInTunnelBridgePreventsTrackModificationEnum(Vehicle *v, void *)
{
if (CheckTrainReservationPreventsTrackModification(Train::From(v)->First()).Failed()) return v;
return nullptr;
}
CommandCost CheckTrainInTunnelBridgePreventsTrackModification(TileIndex start, TileIndex end)
{
if (_settings_game.vehicle.train_braking_model != TBM_REALISTIC) return CommandCost();
if (HasVehicleOnPos(start, VEH_TRAIN, nullptr, &TrainInTunnelBridgePreventsTrackModificationEnum) ||
HasVehicleOnPos(end, VEH_TRAIN, nullptr, &TrainInTunnelBridgePreventsTrackModificationEnum)) {
return_cmd_error(STR_ERROR_CANNOT_MODIFY_TRACK_TRAIN_APPROACHING);
}
return CommandCost();
}
/**
* This is called to retrieve the previous signal, as required
* This is not run all the time as it is somewhat expensive and most restrictions will not test for the previous signal
*/
TileIndex VehiclePosTraceRestrictPreviousSignalCallback(const Train *v, const void *, TraceRestrictPBSEntrySignalAuxField mode)
{
if (mode == TRPESAF_RES_END_TILE) return INVALID_TILE;
TileIndex tile;
Trackdir trackdir;
if (mode == TRPESAF_RES_END && v->lookahead != nullptr) {
tile = v->lookahead->reservation_end_tile;
trackdir = v->lookahead->reservation_end_trackdir;
} else {
if (IsRailDepotTile(v->tile)) {
return v->tile;
}
if (v->track & TRACK_BIT_WORMHOLE && IsTileType(v->tile, MP_TUNNELBRIDGE) && IsTunnelBridgeSignalSimulationExit(v->tile) && IsTunnelBridgeEffectivelyPBS(v->tile)) {
return v->tile;
}
tile = v->tile;
trackdir = v->GetVehicleTrackdir();
}
// scan forwards from vehicle position, for the case that train is waiting at/approaching PBS signal
CFollowTrackRail ft(v);
for (;;) {
if (IsTileType(tile, MP_RAILWAY) && HasSignalOnTrackdir(tile, trackdir)) {
if (HasPbsSignalOnTrackdir(tile, trackdir)) {
// found PBS signal
return tile;
} else {
// wrong type of signal
return INVALID_TILE;
}
}
if (IsTileType(tile, MP_TUNNELBRIDGE) && IsTunnelBridgeSignalSimulationExit(tile) && IsTunnelBridgeEffectivelyPBS(tile) && TrackdirExitsTunnelBridge(tile, trackdir)) {
return tile;
}
// advance to next tile
if (!ft.Follow(tile, trackdir)) {
// ran out of track
return INVALID_TILE;
}
if (KillFirstBit(ft.m_new_td_bits) != TRACKDIR_BIT_NONE) {
// reached a junction tile
return INVALID_TILE;
}
tile = ft.m_new_tile;
trackdir = FindFirstTrackdir(ft.m_new_td_bits);
}
}
/**
* Test whether a train's reservation passes through a given tile.
*/
bool TrainReservationPassesThroughTile(const Train *v, TileIndex search_tile)
{
bool found = false;
FollowReservationEnumerate(v->owner, GetRailTypeInfo(v->railtype)->all_compatible_railtypes, v->tile, v->GetVehicleTrackdir(), FRF_NONE, [&](TileIndex tile, Trackdir trackdir) -> bool {
if (tile == search_tile) {
found = true;
return true;
}
return false;
});
return found;
}
/**
* Determine whether a certain track on a tile is a safe position to end a path.
*
* @param v the vehicle to test for
* @param tile The tile
* @param trackdir The trackdir to test
* @param include_line_end Should end-of-line tiles be considered safe?
* @param forbid_90deg Don't allow trains to make 90 degree turns
* @return True if it is a safe position
*/
bool IsSafeWaitingPosition(const Train *v, TileIndex tile, Trackdir trackdir, bool include_line_end, bool forbid_90deg)
{
if (IsRailDepotTile(tile)) return true;
if (IsTileType(tile, MP_RAILWAY)) {
/* For non-pbs signals, stop on the signal tile. */
if (HasSignalOnTrackdir(tile, trackdir) && !IsPbsSignal(GetSignalType(tile, TrackdirToTrack(trackdir)))) return true;
}
if (IsTunnelBridgeSignalSimulationEntranceTile(tile) && IsTrackAcrossTunnelBridge(tile, TrackdirToTrack(trackdir))) {
return true;
}
/* Check next tile. For performance reasons, we check for 90 degree turns ourself. */
CFollowTrackRail ft(v, GetRailTypeInfo(v->railtype)->all_compatible_railtypes);
/* End of track? */
if (!ft.Follow(tile, trackdir)) {
/* Last tile of a terminus station is a safe position. */
if (include_line_end) return true;
}
/* Check for reachable tracks. */
ft.m_new_td_bits &= DiagdirReachesTrackdirs(ft.m_exitdir);
if (ft.m_tiles_skipped == 0 && Rail90DegTurnDisallowedTilesFromTrackdir(ft.m_old_tile, ft.m_new_tile, ft.m_old_td, forbid_90deg)) ft.m_new_td_bits &= ~TrackdirCrossesTrackdirs(trackdir);
if (ft.m_new_td_bits == TRACKDIR_BIT_NONE) return include_line_end;
if (ft.m_new_td_bits != TRACKDIR_BIT_NONE && KillFirstBit(ft.m_new_td_bits) == TRACKDIR_BIT_NONE) {
Trackdir td = FindFirstTrackdir(ft.m_new_td_bits);
/* PBS signal on next trackdir? Conditionally safe position. */
if (HasPbsSignalOnTrackdir(ft.m_new_tile, td)) {
if (GetSignalType(ft.m_new_tile, TrackdirToTrack(td)) == SIGTYPE_NO_ENTRY) return include_line_end;
if (GetSignalAlwaysReserveThrough(ft.m_new_tile, TrackdirToTrack(td))) return false;
if (IsRestrictedSignal(ft.m_new_tile)) {
const TraceRestrictProgram *prog = GetExistingTraceRestrictProgram(ft.m_new_tile, TrackdirToTrack(td));
if (prog && prog->actions_used_flags & TRPAUF_RESERVE_THROUGH) {
TraceRestrictProgramResult out;
prog->Execute(v, TraceRestrictProgramInput(ft.m_new_tile, td, &VehiclePosTraceRestrictPreviousSignalCallback, nullptr), out);
if (out.flags & TRPRF_RESERVE_THROUGH) {
return false;
}
}
}
return true;
}
/* One-way PBS signal against us? Safe if end-of-line is allowed. */
if (IsTileType(ft.m_new_tile, MP_RAILWAY) && HasSignalOnTrackdir(ft.m_new_tile, ReverseTrackdir(td)) &&
GetSignalType(ft.m_new_tile, TrackdirToTrack(td)) == SIGTYPE_PBS_ONEWAY) {
return include_line_end;
}
if (IsRailTunnelBridgeTile(ft.m_new_tile) &&
IsTrackAcrossTunnelBridge(ft.m_new_tile, TrackdirToTrack(td)) &&
IsTunnelBridgeSignalSimulationExitOnly(ft.m_new_tile) && IsTunnelBridgeEffectivelyPBS(ft.m_new_tile)) {
return include_line_end;
}
}
return false;
}
/**
* Check if a safe position is free.
*
* @param v the vehicle to test for
* @param tile The tile
* @param trackdir The trackdir to test
* @param forbid_90deg Don't allow trains to make 90 degree turns
* @return True if the position is free
*/
bool IsWaitingPositionFree(const Train *v, TileIndex tile, Trackdir trackdir, bool forbid_90deg, PBSWaitingPositionRestrictedSignalInfo *restricted_signal_info)
{
Track track = TrackdirToTrack(trackdir);
TrackBits reserved = GetReservedTrackbits(tile);
/* Tile reserved? Can never be a free waiting position. */
if (TrackOverlapsTracks(reserved, track)) return false;
/* Not reserved and depot or not a pbs signal -> free. */
if (IsRailDepotTile(tile)) return true;
auto pbs_res_end_wait_test = [v, restricted_signal_info](TileIndex t, Trackdir td, bool tunnel_bridge) -> bool {
if (tunnel_bridge ? IsTunnelBridgeRestrictedSignal(t) : IsRestrictedSignal(t)) {
const TraceRestrictProgram *prog = GetExistingTraceRestrictProgram(t, TrackdirToTrack(td));
if (restricted_signal_info && prog) {
restricted_signal_info->tile = t;
restricted_signal_info->trackdir = td;
}
if (prog && prog->actions_used_flags & TRPAUF_PBS_RES_END_WAIT) {
TraceRestrictProgramInput input(t, td, &VehiclePosTraceRestrictPreviousSignalCallback, nullptr);
input.permitted_slot_operations = TRPISP_PBS_RES_END_ACQ_DRY;
TraceRestrictProgramResult out;
prog->Execute(v, input, out);
if (out.flags & TRPRF_PBS_RES_END_WAIT) {
return false;
}
}
}
return true;
};
if (IsTileType(tile, MP_RAILWAY) && HasSignalOnTrackdir(tile, trackdir) && !IsPbsSignal(GetSignalType(tile, track))) {
return pbs_res_end_wait_test(tile, trackdir, false);
}
if (IsTunnelBridgeSignalSimulationEntranceTile(tile) && IsTrackAcrossTunnelBridge(tile, TrackdirToTrack(trackdir))) {
bool free = pbs_res_end_wait_test(tile, trackdir, true);
if (free && IsTunnelBridgeSignalSimulationBidirectional(tile)) {
TileIndex other_end = GetOtherTunnelBridgeEnd(tile);
if (HasAcrossTunnelBridgeReservation(other_end) && GetTunnelBridgeExitSignalState(other_end) == SIGNAL_STATE_RED) return false;
Direction dir = DiagDirToDir(GetTunnelBridgeDirection(other_end));
if (HasVehicleOnPos(other_end, VEH_TRAIN, &dir, [](Vehicle *v, void *data) -> Vehicle * {
DirDiff diff = DirDifference(v->direction, *((Direction *) data));
if (diff == DIRDIFF_SAME) return v;
if (diff == DIRDIFF_45RIGHT || diff == DIRDIFF_45LEFT) {
if (GetAcrossTunnelBridgeTrackBits(v->tile) & Train::From(v)->track) return v;
}
return nullptr;
})) return false;
}
return free;
}
/* Check the next tile, if it's a PBS signal, it has to be free as well. */
CFollowTrackRail ft(v, GetRailTypeInfo(v->railtype)->all_compatible_railtypes);
if (!ft.Follow(tile, trackdir)) return true;
/* Check for reachable tracks. */
ft.m_new_td_bits &= DiagdirReachesTrackdirs(ft.m_exitdir);
if (Rail90DegTurnDisallowedTilesFromTrackdir(ft.m_old_tile, ft.m_new_tile, ft.m_old_td, forbid_90deg)) ft.m_new_td_bits &= ~TrackdirCrossesTrackdirs(trackdir);
if (HasReservedTracks(ft.m_new_tile, TrackdirBitsToTrackBits(ft.m_new_td_bits))) return false;
if (ft.m_new_td_bits != TRACKDIR_BIT_NONE && KillFirstBit(ft.m_new_td_bits) == TRACKDIR_BIT_NONE) {
Trackdir td = FindFirstTrackdir(ft.m_new_td_bits);
/* PBS signal on next trackdir? */
if (HasPbsSignalOnTrackdir(ft.m_new_tile, td)) {
return pbs_res_end_wait_test(ft.m_new_tile, td, false);
}
}
return true;
}