Store tunnel/bridge signal spacing on tile, adjust spacing to fit length

docs/landscape.html

@@ -1741,6 +1741,7 @@
        <li>m6 bit 6: set = PBS signals, clear = block signals</li>
        <li>m6 bit 1: set = semaphore signals, clear = light signals</li>
        <li>m6 bit 0: set = entrance signal shows green, clear = entrance signal shows red</li>
+       <li>m8 bits 15..12: signal simulation spacing</li>
       </ul>
      </li>
      <li>m5 bit 4: pbs reservation state for railway (tunnel only)</li>

docs/landscape_grid.html

@@ -292,7 +292,7 @@ the array so you can quickly see what is used and what is not.
       <td class="bits"><span class="used" title="Bridge or tunnel bit">O</span><span class="patch" title="Signal simulation mode (rail only)">PP</span><span class="rearrange" title="PBS reservation (rail; a rearrangement can free some of these bits)">X</span> <span class="used" title="Transport type">XX</span> <span class="used" title="Direction of the tunnel/bridge">XX</span></td>
       <td class="bits"><span class="patch" title="PBS mode, exit signal state">PP</span><span class="free">OO OO</span><span class="patch" title="Semaphore/light mode, entrance signal state">PP</span></td>
       <td class="bits" rowspan=4><span class="patch" title="Snow/desert present or rail custom bridge head ground type">PPP</span><span class="rearrange" title="Owner of road (road only; a rearrangement can free some of these bits)">X XXXX</span></td>
-      <td class="bits"><span class="free">O</span><span class="patch" title="Road cached one way state">PPP</span> <span class="used" title="Tram type">XXXX XX</span><span class="rearrange" title="Railway type (rail only; a rearrangement can free some of these bits)">XX XXXX</span></td>
+      <td class="bits"><span class="patch" title="Road cached one way state (road only) or signal simulation spacing (rail only)">PPPP</span> <span class="used" title="Tram type">XXXX XX</span><span class="rearrange" title="Railway type (rail only; a rearrangement can free some of these bits)">XX XXXX</span></td>
     </tr>
     <tr>
       <td>bridge ramp - rail</td>
@@ -300,7 +300,7 @@ the array so you can quickly see what is used and what is not.
       <td class="bits"><span class="free">OO</span><span class="patch" title="Track pieces">PP PPPP</span></td>
       <td class="bits"><span class="used" title="Bridge or tunnel bit">1</span><span class="patch" title="Signal simulation mode">PP</span><span class="free">O</span> <span class="used" title="Transport type">00</span> <span class="used" title="Direction of the tunnel/bridge">XX</span></td>
       <td class="bits"><span class="patch" title="PBS mode, exit signal state">PP</span><span class="used" title="Bridge type: wooden, steel,...">XX XX</span><span class="patch" title="Semaphore/light mode, entrance signal state">PP</span></td>
-      <td class="bits"><span class="free">OOOO</span> <span class="patch" title="Secondary railway type (used for bridge-bypassing track when two parallel tracks on custom bridge head)">PPPP PP</span><span class="rearrange" title="Railway type (a rearrangement can free some of these bits)">XX XXXX</span></td>
+      <td class="bits"><span class="patch" title="Signal simulation spacing">PPPP</span> <span class="patch" title="Secondary railway type (used for bridge-bypassing track when two parallel tracks on custom bridge head)">PPPP PP</span><span class="rearrange" title="Railway type (a rearrangement can free some of these bits)">XX XXXX</span></td>
     </tr>
     <tr>
       <td>bridge ramp - road</td>

src/bridge_map.h

@@ -189,6 +189,7 @@ static inline void MakeRailBridgeRamp(TileIndex t, Owner o, BridgeType bridgetyp
 		SB(_me[t].m6, 0, 2, GB(m6_backup, 0, 2));
 		SB(_me[t].m6, 6, 1, GB(m6_backup, 6, 1));
 		SB(_me[t].m8, 6, 6, GB(m8_backup, 6, 6));
+		SB(_me[t].m8, 12, 4, GB(m8_backup, 12, 4));
 	} else {
 		/* Set bridge head tracks to axial track only. */
 		SB(_m[t].m4, 0, 6, DiagDirToDiagTrackBits(d));

src/lang/english.txt

@@ -1879,6 +1879,7 @@ STR_CONFIG_SETTING_MIN_YEARS_FOR_SHARES_HELPTEXT                :Set the minimum
 STR_CONFIG_SETTING_FEEDER_PAYMENT_SHARE                         :Percentage of leg profit to pay in feeder systems: {STRING2}
 STR_CONFIG_SETTING_FEEDER_PAYMENT_SHARE_HELPTEXT                :Percentage of income given to the intermediate legs in feeder systems, giving more control over the income
 STR_CONFIG_SETTING_SIMULATE_SIGNALS                             :Simulate signals in tunnels, bridges every: {STRING2}
+STR_CONFIG_SETTING_SIMULATE_SIGNALS_HELPTEXT                    :This sets the target signal spacing for newly signalled bridges and tunnels. The actual spacing may slightly differ from this to avoid uneven spacing. Changing this setting does not re-signal existing signalled bridges and tunnels.
 STR_CONFIG_SETTING_SIMULATE_SIGNALS_VALUE                       :{COMMA} tile{P 0 "" s}
 STR_CONFIG_SETTING_DAY_LENGTH_FACTOR                            :Day length factor: {STRING2}
 STR_CONFIG_SETTING_DAY_LENGTH_FACTOR_HELPTEXT                   :Game pace is slowed by this factor

src/rail_cmd.cpp

@@ -1527,8 +1527,11 @@ CommandCost CmdBuildSingleSignal(TileIndex tile, DoCommandFlag flags, uint32 p1,
 			Company * const c = Company::Get(GetTileOwner(tile));
 			std::vector<Train *> re_reserve_trains;
 			if (IsTunnelBridgeWithSignalSimulation(tile)) {
-				c->infrastructure.signal -= GetTunnelBridgeSignalSimulationSignalCount(c, tile, tile_exit);
+				c->infrastructure.signal -= GetTunnelBridgeSignalSimulationSignalCount(tile, tile_exit);
 			} else {
+				uint spacing = GetBestTunnelBridgeSignalSimulationSpacing(GetTileOwner(tile), tile, tile_exit);
+				SetTunnelBridgeSignalSimulationSpacing(tile, spacing);
+				SetTunnelBridgeSignalSimulationSpacing(tile_exit, spacing);
 				for (TileIndex t : { tile, tile_exit }) {
 					if (HasAcrossTunnelBridgeReservation(t)) {
 						Train *re_reserve_train = GetTrainForReservation(t, FindFirstTrack(GetAcrossTunnelBridgeReservationTrackBits(t)));
@@ -1602,7 +1605,7 @@ CommandCost CmdBuildSingleSignal(TileIndex tile, DoCommandFlag flags, uint32 p1,
 			AddSideToSignalBuffer(tile_exit, INVALID_DIAGDIR, GetTileOwner(tile));
 			YapfNotifyTrackLayoutChange(tile, track);
 			YapfNotifyTrackLayoutChange(tile_exit, track);
-			if (IsTunnelBridgeWithSignalSimulation(tile)) c->infrastructure.signal += GetTunnelBridgeSignalSimulationSignalCount(c, tile, tile_exit);
+			if (IsTunnelBridgeWithSignalSimulation(tile)) c->infrastructure.signal += GetTunnelBridgeSignalSimulationSignalCount(tile, tile_exit);
 			DirtyCompanyInfrastructureWindows(GetTileOwner(tile));
 			for (Train *re_reserve_train : re_reserve_trains) {
 				ReReserveTrainPath(re_reserve_train);
@@ -2095,7 +2098,7 @@ CommandCost CmdRemoveSingleSignal(TileIndex tile, DoCommandFlag flags, uint32 p1
 		}
 		if (flags & DC_EXEC) {
 			Company *c = Company::Get(GetTileOwner(tile));
-			c->infrastructure.signal -= GetTunnelBridgeSignalSimulationSignalCount(c, tile, end);
+			c->infrastructure.signal -= GetTunnelBridgeSignalSimulationSignalCount(tile, end);
 			ClearBridgeTunnelSignalSimulation(end, tile);
 			ClearBridgeTunnelSignalSimulation(tile, end);
 			MarkBridgeOrTunnelDirty(tile);

src/saveload/afterload.cpp

@@ -29,6 +29,7 @@
 #include "../station_base.h"
 #include "../waypoint_base.h"
 #include "../roadstop_base.h"
+#include "../tunnelbridge.h"
 #include "../tunnelbridge_map.h"
 #include "../pathfinder/yapf/yapf_cache.h"
 #include "../elrail_func.h"
@@ -3637,6 +3638,22 @@ bool AfterLoadGame()
 			c->settings.simulated_wormhole_signals = _settings_game.construction.old_simulated_wormhole_signals;
 		}
 	}
+	if (SlXvIsFeaturePresent(XSLFI_SIG_TUNNEL_BRIDGE, 1, 8)) {
+		/* spacing made per tunnel/bridge */
+		for (TileIndex t = 0; t < map_size; t++) {
+			if (IsTileType(t, MP_TUNNELBRIDGE) && GetTunnelBridgeTransportType(t) == TRANSPORT_RAIL && IsTunnelBridgeWithSignalSimulation(t)) {
+				DiagDirection dir = GetTunnelBridgeDirection(t);
+				if (dir == DIAGDIR_NE || dir == DIAGDIR_SE) {
+					TileIndex other = GetOtherTunnelBridgeEnd(t);
+					uint spacing = GetBestTunnelBridgeSignalSimulationSpacing(GetTileOwner(t), t, other);
+					SetTunnelBridgeSignalSimulationSpacing(t, spacing);
+					SetTunnelBridgeSignalSimulationSpacing(other, spacing);
+				}
+			}
+		}
+		/* force aspect re-calculation */
+		_extra_aspects = 0;
+	}
 
 	if (SlXvIsFeatureMissing(XSLFI_CUSTOM_BRIDGE_HEADS)) {
 		/* ensure that previously unused custom bridge-head bits are cleared */

src/saveload/extended_ver_sl.cpp

@@ -85,7 +85,7 @@ const SlxiSubChunkInfo _sl_xv_sub_chunk_infos[] = {
 	{ XSLFI_DEPARTURE_BOARDS,       XSCF_IGNORABLE_UNKNOWN,   1,   1, "departure_boards",          nullptr, nullptr, nullptr        },
 	{ XSLFI_TIMETABLES_START_TICKS, XSCF_NULL,                2,   2, "timetable_start_ticks",     nullptr, nullptr, nullptr        },
 	{ XSLFI_TOWN_CARGO_ADJ,         XSCF_IGNORABLE_UNKNOWN,   2,   2, "town_cargo_adj",            nullptr, nullptr, nullptr        },
-	{ XSLFI_SIG_TUNNEL_BRIDGE,      XSCF_NULL,                8,   8, "signal_tunnel_bridge",      nullptr, nullptr, "XBSS"      },
+	{ XSLFI_SIG_TUNNEL_BRIDGE,      XSCF_NULL,                9,   9, "signal_tunnel_bridge",      nullptr, nullptr, "XBSS"      },
 	{ XSLFI_IMPROVED_BREAKDOWNS,    XSCF_NULL,                7,   7, "improved_breakdowns",       nullptr, nullptr, nullptr        },
 	{ XSLFI_CONSIST_BREAKDOWN_FLAG, XSCF_NULL,                1,   1, "consist_breakdown_flag",    nullptr, nullptr, nullptr        },
 	{ XSLFI_TT_WAIT_IN_DEPOT,       XSCF_NULL,                1,   1, "tt_wait_in_depot",          nullptr, nullptr, nullptr        },

src/settings.cpp

@@ -1482,14 +1482,6 @@ static bool InvalidateCompanyWindow(int32 p1)
 	return true;
 }
 
-static bool SimulatedWormholeSignalsChanged(int32 p1)
-{
-	extern void AfterLoadCompanyStats();
-	AfterLoadCompanyStats();
-	MarkWholeScreenDirty();
-	return true;
-}
-
 static bool EnableSingleVehSharedOrderGuiChanged(int32)
 {
 	for (VehicleType type = VEH_BEGIN; type < VEH_COMPANY_END; type++) {

src/table/company_settings.ini

@@ -11,7 +11,6 @@ static bool UpdateIntervalTrains(int32 p1);
 static bool UpdateIntervalRoadVeh(int32 p1);
 static bool UpdateIntervalShips(int32 p1);
 static bool UpdateIntervalAircraft(int32 p1);
-static bool SimulatedWormholeSignalsChanged(int32 p1);
 
 static const SettingDesc _company_settings[] = {
 [post-amble]
@@ -269,8 +268,8 @@ def      = 4
 min      = 1
 max      = 16
 str      = STR_CONFIG_SETTING_SIMULATE_SIGNALS
+strhelp  = STR_CONFIG_SETTING_SIMULATE_SIGNALS_HELPTEXT
 strval   = STR_CONFIG_SETTING_SIMULATE_SIGNALS_VALUE
-proc     = SimulatedWormholeSignalsChanged
 cat      = SC_ADVANCED
 patxname = ""simulated_wormhole_signals""
 

src/tunnelbridge.h

@@ -13,8 +13,9 @@
 #include "map_func.h"
 #include "tile_map.h"
 
-uint GetTunnelBridgeSignalSimulationSpacing(TileIndex tile);
+uint GetTunnelBridgeSignalSimulationSpacingTarget(Owner owner);
-uint GetTunnelBridgeSignalSimulationSignalCount(Company *c, TileIndex begin, TileIndex end);
+uint GetBestTunnelBridgeSignalSimulationSpacing(Owner owner, TileIndex begin, TileIndex end);
+uint GetTunnelBridgeSignalSimulationSignalCount(TileIndex begin, TileIndex end);
 
 /**
  * Calculates the length of a tunnel or a bridge (without end tiles)

src/tunnelbridge_cmd.cpp

@@ -131,9 +131,8 @@ void MarkBridgeOrTunnelDirtyOnReservationChange(TileIndex tile, ViewportMarkDirt
 	}
 }
 
-uint GetTunnelBridgeSignalSimulationSpacing(TileIndex tile)
+uint GetTunnelBridgeSignalSimulationSpacingTarget(Owner owner)
 {
-	Owner owner = GetTileOwner(tile);
 	if (Company::IsValidID(owner)) {
 		return Company::Get(owner)->settings.simulated_wormhole_signals;
 	} else {
@@ -141,16 +140,37 @@ uint GetTunnelBridgeSignalSimulationSpacing(TileIndex tile)
 	}
 }
 
+uint GetBestTunnelBridgeSignalSimulationSpacing(Owner owner, TileIndex begin, TileIndex end)
+{
+	int target = GetTunnelBridgeSignalSimulationSpacingTarget(owner);
+	if (target <= 2) return target;
+	int length = GetTunnelBridgeLength(begin, end);
+	if (target > length || ((length + 1) % target) == 0) return target;
+
+	int lower = target - (target / 4);
+	int upper = std::min<int>(16, target + (target / 3));
+
+	int best_gap = -1;
+	int best_spacing = 0;
+	for (int i = lower; i <= upper; i++) {
+		int gap = length % i;
+		if (gap > best_gap) {
+			best_gap = gap;
+			best_spacing = i;
+		}
+	}
+	return best_spacing;
+}
+
 /**
  * Get number of signals on bridge or tunnel with signal simulation.
- * @param c     Company to use.
  * @param begin The begin of the tunnel or bridge.
  * @param end   The end of the tunnel or bridge.
  * @pre IsTunnelBridgeWithSignalSimulation(begin)
  */
-uint GetTunnelBridgeSignalSimulationSignalCount(Company *c, TileIndex begin, TileIndex end)
+uint GetTunnelBridgeSignalSimulationSignalCount(TileIndex begin, TileIndex end)
 {
-	uint result = 2 + (GetTunnelBridgeLength(begin, end) / c->settings.simulated_wormhole_signals);
+	uint result = 2 + (GetTunnelBridgeLength(begin, end) / GetTunnelBridgeSignalSimulationSpacing(begin));
 	if (IsTunnelBridgeSignalSimulationBidirectional(begin)) result *= 2;
 	return result;
 }
@@ -1254,7 +1274,7 @@ static CommandCost DoClearTunnel(TileIndex tile, DoCommandFlag flags)
 				Company *c = Company::Get(owner);
 				c->infrastructure.rail[GetRailType(tile)] -= len * TUNNELBRIDGE_TRACKBIT_FACTOR;
 				if (IsTunnelBridgeWithSignalSimulation(tile)) { // handle tunnel/bridge signals.
-					c->infrastructure.signal -= GetTunnelBridgeSignalSimulationSignalCount(c, tile, endtile);
+					c->infrastructure.signal -= GetTunnelBridgeSignalSimulationSignalCount(tile, endtile);
 				}
 				DirtyCompanyInfrastructureWindows(owner);
 			}
@@ -2730,9 +2750,9 @@ static void UpdateRailTunnelBridgeInfrastructure(Company *c, TileIndex begin, Ti
 
 		if (IsTunnelBridgeWithSignalSimulation(begin)) {
 			if (add) {
-				c->infrastructure.signal += GetTunnelBridgeSignalSimulationSignalCount(c, begin, end);
+				c->infrastructure.signal += GetTunnelBridgeSignalSimulationSignalCount(begin, end);
 			} else {
-				c->infrastructure.signal -= GetTunnelBridgeSignalSimulationSignalCount(c, begin, end);
+				c->infrastructure.signal -= GetTunnelBridgeSignalSimulationSignalCount(begin, end);
 			}
 		}
 	}

src/tunnelbridge_map.h

@@ -530,6 +530,18 @@ static inline void SetTunnelBridgeExitSignalAspect(TileIndex t, uint8 aspect)
 	SB(_m[t].m3, 3, 3, aspect);
 }
 
+static inline uint GetTunnelBridgeSignalSimulationSpacing(TileIndex t)
+{
+	assert_tile(IsRailTunnelBridgeTile(t), t);
+	return 1 + GB(_me[t].m8, 12, 4);
+}
+
+static inline void SetTunnelBridgeSignalSimulationSpacing(TileIndex t, uint spacing)
+{
+	assert_tile(IsRailTunnelBridgeTile(t), t);
+	SB(_me[t].m8, 12, 4, spacing - 1);
+}
+
 static inline Trackdir GetTunnelBridgeExitTrackdir(TileIndex t, DiagDirection tunnel_bridge_dir)
 {
 	return TrackEnterdirToTrackdir((Track)FIND_FIRST_BIT(GetAcrossTunnelBridgeTrackBits(t)), ReverseDiagDir(tunnel_bridge_dir));