Add NewGRF railtype flag to disable realistic braking for vehs of that type

See: #242

docs/newgrf-additions-nml.html

@@ -40,6 +40,11 @@
 			This flag must only be set if a different sprite is returned when bit 24 of <span class="code">extra_callback_info2</span> is set.
 		</td>
 	</tr>
+	<tr><td>disable_realistic_braking</td><td>0 or 1</td>
+		<td>
+			When this property is set realistic braking is disabled for trains of this railtype even when realistic braking is otherwise in effect.
+		</td>
+	</tr>
 	</table>
 	<h3><a href="https://newgrf-specs.tt-wiki.net/wiki/NML:Roadtypes#Roadtype_properties">Roadtype properties</a></h3>
 	<table>

docs/newgrf-additions.html

@@ -231,6 +231,12 @@
 	The property length is 1 byte. 0 is disabled (default). 1 is enabled.
 	</p>
 	<p>This is indicated by the feature name: <font face="monospace">action0_railtype_restricted_signals</font>, version 1</p>
+	<h4>Disable use of realistic braking with this rail type (mappable property: railtype_disable_realistic_braking)</h4>
+	<p>This applies to <a href="https://newgrf-specs.tt-wiki.net/wiki/Action3/Railtypes#Signal_sprites_.280B.29">Action 2/3 - Railtype custom signal sprites</a>.<br />
+	When this property is set realistic braking is disabled for trains of this railtype even when realistic braking is otherwise in effect.<br />
+	The property length is 1 byte. 0 is realistic braking is not disabled for this railtype. 1 is disable realistic braking for this railtype.
+	</p>
+	<p>This is indicated by the feature name: <font face="monospace">action0_railtype_disable_realistic_braking</font>, version 1</p>
 	<br />
 	<h3><a href="https://newgrf-specs.tt-wiki.net/wiki/Action0/Roadtypes">Action 0 - Roadtypes</a> and <a href="https://newgrf-specs.tt-wiki.net/wiki/Action0/Tramtypes">Action 0 - Tramtypes</a></h3>
 	<h4>Extra road/tram type flags (mappable property: roadtype_extra_flags)</h4>

src/console_cmds.cpp

@@ -2468,7 +2468,7 @@ DEF_CONSOLE_CMD(ConDumpRailTypes)
 			grfid = grf->grfid;
 			grfs.insert(std::pair<uint32, const GRFFile *>(grfid, grf));
 		}
-		IConsolePrintF(CC_DEFAULT, "  %02u %c%c%c%c, Flags: %c%c%c%c%c%c, Ctrl Flags: %c%c, GRF: %08X, %s",
+		IConsolePrintF(CC_DEFAULT, "  %02u %c%c%c%c, Flags: %c%c%c%c%c%c, Ctrl Flags: %c%c%c, GRF: %08X, %s",
 				(uint) rt,
 				rti->label >> 24, rti->label >> 16, rti->label >> 8, rti->label,
 				HasBit(rti->flags, RTF_CATENARY)            ? 'c' : '-',
@@ -2479,6 +2479,7 @@ DEF_CONSOLE_CMD(ConDumpRailTypes)
 				HasBit(rti->flags, RTF_DISALLOW_90DEG)      ? 'd' : '-',
 				HasBit(rti->ctrl_flags, RTCF_PROGSIG)       ? 'p' : '-',
 				HasBit(rti->ctrl_flags, RTCF_RESTRICTEDSIG) ? 'r' : '-',
+				HasBit(rti->ctrl_flags, RTCF_NOREALISTICBRAKING) ? 'b' : '-',
 				BSWAP32(grfid),
 				GetStringPtr(rti->strings.name)
 		);

src/newgrf.cpp

@@ -4377,6 +4377,11 @@ static ChangeInfoResult RailTypeChangeInfo(uint id, int numinfo, int prop, const
 				SB(rti->ctrl_flags, RTCF_RESTRICTEDSIG, 1, (buf->ReadByte() != 0 ? 1 : 0));
 				break;
 
+			case A0RPI_RAILTYPE_DISABLE_REALISTIC_BRAKING:
+				if (MappedPropertyLengthMismatch(buf, 1, mapping_entry)) break;
+				SB(rti->ctrl_flags, RTCF_NOREALISTICBRAKING, 1, (buf->ReadByte() != 0 ? 1 : 0));
+				break;
+
 			default:
 				ret = HandleAction0PropertyDefault(buf, prop);
 				break;
@@ -4459,6 +4464,7 @@ static ChangeInfoResult RailTypeReserveInfo(uint id, int numinfo, int prop, cons
 
 			case A0RPI_RAILTYPE_ENABLE_PROGRAMMABLE_SIGNALS:
 			case A0RPI_RAILTYPE_ENABLE_RESTRICTED_SIGNALS:
+			case A0RPI_RAILTYPE_DISABLE_REALISTIC_BRAKING:
 				buf->Skip(buf->ReadExtendedByte());
 				break;
 
@@ -8403,6 +8409,7 @@ static const GRFFeatureInfo _grf_feature_list[] = {
 	GRFFeatureInfo("action5_programmable_signals", 1),
 	GRFFeatureInfo("action0_railtype_programmable_signals", 1),
 	GRFFeatureInfo("action0_railtype_restricted_signals", 1),
+	GRFFeatureInfo("action0_railtype_disable_realistic_braking", 1),
 	GRFFeatureInfo("action0_roadtype_extra_flags", 1),
 	GRFFeatureInfo(),
 };
@@ -8522,6 +8529,7 @@ static const GRFPropertyMapDefinition _grf_action0_remappable_properties[] = {
 	GRFPropertyMapDefinition(GSF_BRIDGES, A0RPI_BRIDGE_AVAILABILITY_FLAGS, "bridge_availability_flags"),
 	GRFPropertyMapDefinition(GSF_RAILTYPES, A0RPI_RAILTYPE_ENABLE_PROGRAMMABLE_SIGNALS, "railtype_enable_programmable_signals"),
 	GRFPropertyMapDefinition(GSF_RAILTYPES, A0RPI_RAILTYPE_ENABLE_RESTRICTED_SIGNALS, "railtype_enable_restricted_signals"),
+	GRFPropertyMapDefinition(GSF_RAILTYPES, A0RPI_RAILTYPE_DISABLE_REALISTIC_BRAKING, "railtype_disable_realistic_braking"),
 	GRFPropertyMapDefinition(GSF_ROADTYPES, A0RPI_ROADTYPE_EXTRA_FLAGS, "roadtype_extra_flags"),
 	GRFPropertyMapDefinition(GSF_TRAMTYPES, A0RPI_ROADTYPE_EXTRA_FLAGS, "roadtype_extra_flags"),
 	GRFPropertyMapDefinition(),

src/newgrf.h

@@ -117,6 +117,7 @@ enum Action0RemapPropertyIds {
 	A0RPI_BRIDGE_AVAILABILITY_FLAGS,
 	A0RPI_RAILTYPE_ENABLE_PROGRAMMABLE_SIGNALS,
 	A0RPI_RAILTYPE_ENABLE_RESTRICTED_SIGNALS,
+	A0RPI_RAILTYPE_DISABLE_REALISTIC_BRAKING,
 	A0RPI_ROADTYPE_EXTRA_FLAGS,
 };
 

src/rail.h

@@ -43,8 +43,9 @@ DECLARE_ENUM_AS_BIT_SET(RailTypeFlags)
 
 /** Railtype control flags. */
 enum RailTypeCtrlFlags {
-	RTCF_PROGSIG           = 0,                          ///< Custom signal sprites enabled for programmable pre-signals.
+	RTCF_PROGSIG                = 0,                          ///< Custom signal sprites enabled for programmable pre-signals.
-	RTCF_RESTRICTEDSIG     = 1,                          ///< Custom signal sprite flag enabled for restricted signals.
+	RTCF_RESTRICTEDSIG          = 1,                          ///< Custom signal sprite flag enabled for restricted signals.
+	RTCF_NOREALISTICBRAKING     = 2,                          ///< Realistic braking disabled for this track type
 };
 
 struct SpriteGroup;

src/table/newgrf_debug_data.h

@@ -838,9 +838,10 @@ class NIHRailType : public NIHelper {
 					HasBit(info->flags, RTF_ALLOW_90DEG) ? 'a' : '-',
 					HasBit(info->flags, RTF_DISALLOW_90DEG) ? 'd' : '-');
 			print(buffer);
-			seprintf(buffer, lastof(buffer), "  Ctrl flags: %c%c",
+			seprintf(buffer, lastof(buffer), "  Ctrl flags: %c%c%c",
 					HasBit(info->ctrl_flags, RTCF_PROGSIG) ? 'p' : '-',
-					HasBit(info->ctrl_flags, RTCF_RESTRICTEDSIG) ? 'r' : '-');
+					HasBit(info->ctrl_flags, RTCF_RESTRICTEDSIG) ? 'r' : '-',
+					HasBit(info->ctrl_flags, RTCF_NOREALISTICBRAKING) ? 'b' : '-');
 			print(buffer);
 			seprintf(buffer, lastof(buffer), "  Powered: 0x" OTTD_PRINTFHEX64, info->powered_railtypes);
 			print(buffer);

src/train_cmd.cpp

@@ -1073,7 +1073,7 @@ void Train::UpdateAcceleration()
 	assert(weight != 0);
 	this->acceleration = Clamp(power / weight * 4, 1, 255);
 
-	if (_settings_game.vehicle.train_braking_model == TBM_REALISTIC) {
+	if (_settings_game.vehicle.train_braking_model == TBM_REALISTIC && !HasBit(GetRailTypeInfo(this->railtype)->ctrl_flags, RTCF_NOREALISTICBRAKING)) {
 		this->tcache.cached_tflags |= TCF_RL_BRAKING;
 		switch (_settings_game.vehicle.train_acceleration_model) {
 			default: NOT_REACHED();