NewGRF: Only extend value of road stops variable 68 if feature tested for

docs/newgrf-roadstops.html

@@ -341,7 +341,9 @@
 	<tr><th>Bits</th><th>Meaning</th></tr>
 	<tr><td>0 - 7</td><td>
 		If the tile is defined in the current GRF, this is the lower 8 bits of the setID used in the definition. Otherwise, the content is undefined.<br />
-		Note that if this GRF has any road stop setIDs greater than 255, bits 24 - 31 need to be used as well.
+		Note that if this GRF has any road stop setIDs greater than 255, bits 24 - 31 need to be used as well.<br />
+		<br />
+		If the <font face="monospace">road_stops</font> feature is not tested for, this is the entire setID, clamped to the range 0..255.
 	</td></tr>
 	<tr><td>8 - 9</td><td>
 		0 - The tile uses original TTD graphics<br />
@@ -367,7 +369,9 @@
 	<tr><td>24 - 31</td><td>
 		If the tile is defined in the current GRF, this is the upper 8 bits of the setID used in the definition. Otherwise, the content is undefined.<br />
 		This can be ignored if this GRF does not have any road stop setIDs greater than 255 (does not define more than 256 road stop types).<br />
-		This requires <font face="monospace">road_stops</font>, version 7.
+		This requires <font face="monospace">road_stops</font>, version 7.<br />
+		<br />
+		If the <font face="monospace">road_stops</font> feature is not tested for, this is set to 0.
 	</td></tr>
 	</table>
 	<br />

src/newgrf.cpp

@@ -5973,6 +5973,11 @@ static void NewSpriteGroup(ByteReader *buf)
 					}
 				}
 
+				if (info.scope_feature == GSF_ROADSTOPS && HasBit(_cur.grffile->observed_feature_tests, GFTOF_ROAD_STOPS)) {
+					if (adjust.variable == 0x68) adjust.variable = A2VRI_ROADSTOP_INFO_NEARBY_TILES_EXT;
+					if (adjust.variable == 0x7B && adjust.parameter == 0x68) adjust.parameter = A2VRI_ROADSTOP_INFO_NEARBY_TILES_EXT;
+				}
+
 				if (adjust.type != DSGA_TYPE_NONE) {
 					adjust.add_val    = buf->ReadVarSize(varsize);
 					adjust.divmod_val = buf->ReadVarSize(varsize);

src/newgrf_extension.cpp

@@ -60,7 +60,7 @@ extern const GRFFeatureInfo _grf_feature_list[] = {
 	GRFFeatureInfo("action0_object_edge_foundation_mode", 2),
 	GRFFeatureInfo("action0_object_flood_resistant", 1),
 	GRFFeatureInfo("action0_object_viewport_map_tile_type", 1),
-	GRFFeatureInfo("road_stops", 9),
+	GRFFeatureInfo("road_stops", 9, GFTOF_ROAD_STOPS),
 	GRFFeatureInfo("new_landscape", 2),
 	GRFFeatureInfo("more_objects_per_grf", 1, GFTOF_MORE_OBJECTS_PER_GRF),
 	GRFFeatureInfo("more_action2_ids", 1, GFTOF_MORE_ACTION2_IDS),

src/newgrf_extension.h

@@ -79,6 +79,7 @@ enum Action2VariableRemapIds {
 	A2VRI_OBJECT_FOUNDATION_SLOPE = 0x100,
 	A2VRI_OBJECT_FOUNDATION_SLOPE_CHANGE,
 	A2VRI_VEHICLE_CURRENT_SPEED_SCALED,
+	A2VRI_ROADSTOP_INFO_NEARBY_TILES_EXT,
 	A2VRI_ROADSTOP_INFO_NEARBY_TILES_V2,
 	A2VRI_RAILTYPE_SIGNAL_RESTRICTION_INFO,
 	A2VRI_RAILTYPE_SIGNAL_CONTEXT,
@@ -105,6 +106,7 @@ enum GRFFeatureTestObservationFlag : uint8 {
 	GFTOF_TOWN_ZONE_CALLBACK,
 	GFTOF_MORE_VARACTION2_TYPES,
 	GFTOF_MULTI_PART_SHIPS,
+	GFTOF_ROAD_STOPS,
 
 	GFTOF_INVALID = 0xFF,
 };

src/newgrf_optimiser.cpp

@@ -94,6 +94,8 @@ static bool IsExpensiveRoadStopsVariable(uint16 variable)
 		case 0x68:
 		case 0x6A:
 		case 0x6B:
+		case A2VRI_ROADSTOP_INFO_NEARBY_TILES_EXT:
+		case A2VRI_ROADSTOP_INFO_NEARBY_TILES_V2:
 			return true;
 
 		default:

src/newgrf_roadstop.cpp

@@ -67,7 +67,7 @@ uint32 RoadStopScopeResolver::GetTriggers() const
 	return this->st == nullptr ? 0 : this->st->waiting_triggers;
 }
 
-uint32 RoadStopScopeResolver::GetNearbyRoadStopsInfo(uint32 parameter, bool v2) const
+uint32 RoadStopScopeResolver::GetNearbyRoadStopsInfo(uint32 parameter, RoadStopScopeResolver::NearbyRoadStopInfoMode mode) const
 {
 	if (this->tile == INVALID_TILE) return 0xFFFFFFFF;
 	TileIndex nearby_tile = GetNearbyTile(parameter, this->tile);
@@ -93,10 +93,16 @@ uint32 RoadStopScopeResolver::GetNearbyRoadStopsInfo(uint32 parameter, bool v2)
 		res |= (GetDriveThroughStopDisallowedRoadDirections(nearby_tile) << 21);
 	}
 
-	if (v2) {
-		return (res << 8) | localidx;
-	} else {
-		return res | (localidx & 0xFF) | ((localidx & 0xFF00) << 16);
+	switch (mode) {
+		case NearbyRoadStopInfoMode::Standard:
+		default:
+			return res | std::min<uint16>(localidx, 0xFF);
+
+		case NearbyRoadStopInfoMode::Extended:
+			return res | (localidx & 0xFF) | ((localidx & 0xFF00) << 16);
+
+		case NearbyRoadStopInfoMode::V2:
+			return (res << 8) | localidx;
 	}
 }
 
@@ -191,12 +197,17 @@ uint32 RoadStopScopeResolver::GetVariable(uint16 variable, uint32 parameter, Get
 
 		/* Road stop info of nearby tiles */
 		case 0x68: {
-			return this->GetNearbyRoadStopsInfo(parameter, false);
+			return this->GetNearbyRoadStopsInfo(parameter, NearbyRoadStopInfoMode::Standard);
+		}
+
+		/* Road stop info of nearby tiles: extended */
+		case A2VRI_ROADSTOP_INFO_NEARBY_TILES_EXT: {
+			return this->GetNearbyRoadStopsInfo(parameter,  NearbyRoadStopInfoMode::Extended);
 		}
 
 		/* Road stop info of nearby tiles: v2 */
 		case A2VRI_ROADSTOP_INFO_NEARBY_TILES_V2: {
-			return this->GetNearbyRoadStopsInfo(parameter, true);
+			return this->GetNearbyRoadStopsInfo(parameter,  NearbyRoadStopInfoMode::V2);
 		}
 
 		/* GRFID of nearby road stop tiles */

src/newgrf_roadstop.h

@@ -102,7 +102,12 @@ struct RoadStopScopeResolver : public ScopeResolver {
 	uint32 GetVariable(uint16 variable, uint32 parameter, GetVariableExtra *extra) const override;
 
 private:
-	uint32 GetNearbyRoadStopsInfo(uint32 parameter, bool v2) const;
+	enum class NearbyRoadStopInfoMode {
+		Standard,
+		Extended,
+		V2,
+	};
+	uint32 GetNearbyRoadStopsInfo(uint32 parameter, NearbyRoadStopInfoMode mode) const;
 };
 
 /** Road stop resolver. */

src/table/newgrf_debug_data.h

@@ -1945,6 +1945,7 @@ static const NIVariable _nif_roadstops[] = {
 	NIV(0x69, "information about cargo accepted in the past"),
 	NIV(0x6A, "GRFID of nearby road stop tiles"),
 	NIV(0x6B, "Road info of nearby plain road tiles"),
+	NIV(A2VRI_ROADSTOP_INFO_NEARBY_TILES_EXT, "road stop info of nearby tiles ext"),
 	NIV(A2VRI_ROADSTOP_INFO_NEARBY_TILES_V2, "road stop info of nearby tiles v2"),
 	NIV_END(),
 };