Fix #13980: Allow diagonal selection for road convert (#13983)

Fixes #13980

src/road_cmd.cpp

@@ -857,7 +857,7 @@ do_clear:;
 				if (HasPowerOnRoad(rt, existing_rt)) {
 					rt = existing_rt;
 				} else if (HasPowerOnRoad(existing_rt, rt)) {
-					ret = Command<CMD_CONVERT_ROAD>::Do(flags, tile, tile, rt);
+					ret = Command<CMD_CONVERT_ROAD>::Do(flags, tile, tile, rt, false);
 					if (ret.Failed()) return ret;
 					cost.AddCost(ret.GetCost());
 				} else {
@@ -2435,7 +2435,7 @@ static void ConvertRoadTypeOwner(TileIndex tile, uint num_pieces, Owner owner, R
  * @param to_type new roadtype to convert to.
  * @return the cost of this operation or an error
  */
-CommandCost CmdConvertRoad(DoCommandFlags flags, TileIndex tile, TileIndex area_start, RoadType to_type)
+CommandCost CmdConvertRoad(DoCommandFlags flags, TileIndex tile, TileIndex area_start, RoadType to_type, bool diagonal)
 {
 	TileIndex area_end = tile;
 
@@ -2449,7 +2449,7 @@ CommandCost CmdConvertRoad(DoCommandFlags flags, TileIndex tile, TileIndex area_
 	CommandCost error = CommandCost((rtt == RTT_TRAM) ? STR_ERROR_NO_SUITABLE_TRAMWAY : STR_ERROR_NO_SUITABLE_ROAD); // by default, there is no road to convert.
 	bool found_convertible_road = false; // whether we actually did convert any road/tram (see bug #7633)
 
-	std::unique_ptr<TileIterator> iter = std::make_unique<OrthogonalTileIterator>(area_start, area_end);
+	std::unique_ptr<TileIterator> iter = TileIterator::Create(area_start, area_end, diagonal);
 	for (; (tile = *iter) != INVALID_TILE; ++(*iter)) {
 		/* Is road present on tile? */
 		if (!MayHaveRoad(tile)) continue;
@@ -2552,7 +2552,11 @@ CommandCost CmdConvertRoad(DoCommandFlags flags, TileIndex tile, TileIndex area_
 			/* If both ends of tunnel/bridge are in the range, do not try to convert twice -
 			 * it would cause assert because of different test and exec runs */
 			if (endtile < tile) {
-				if (OrthogonalTileArea(area_start, area_end).Contains(endtile)) continue;
+				if (diagonal) {
+					if (DiagonalTileArea(area_start, area_end).Contains(endtile)) continue;
+				} else {
+					if (OrthogonalTileArea(area_start, area_end).Contains(endtile)) continue;
+				}
 			}
 
 			/* When not converting rail <-> el. rail, any vehicle cannot be in tunnel/bridge */

src/road_cmd.h

@@ -23,7 +23,7 @@ CommandCost CmdBuildLongRoad(DoCommandFlags flags, TileIndex end_tile, TileIndex
 std::tuple<CommandCost, Money> CmdRemoveLongRoad(DoCommandFlags flags, TileIndex end_tile, TileIndex start_tile, RoadType rt, Axis axis, bool start_half, bool end_half);
 CommandCost CmdBuildRoad(DoCommandFlags flags, TileIndex tile, RoadBits pieces, RoadType rt, DisallowedRoadDirections toggle_drd, TownID town_id);
 CommandCost CmdBuildRoadDepot(DoCommandFlags flags, TileIndex tile, RoadType rt, DiagDirection dir);
-CommandCost CmdConvertRoad(DoCommandFlags flags, TileIndex tile, TileIndex area_start, RoadType to_type);
+CommandCost CmdConvertRoad(DoCommandFlags flags, TileIndex tile, TileIndex area_start, RoadType to_type, bool diagonal);
 
 DEF_CMD_TRAIT(CMD_BUILD_LONG_ROAD,  CmdBuildLongRoad,  CommandFlags({CommandFlag::Auto, CommandFlag::NoWater, CommandFlag::Deity}), CMDT_LANDSCAPE_CONSTRUCTION)
 DEF_CMD_TRAIT(CMD_REMOVE_LONG_ROAD, CmdRemoveLongRoad, CommandFlags({CommandFlag::Auto, CommandFlag::NoTest}),              CMDT_LANDSCAPE_CONSTRUCTION) // towns may disallow removing road bits (as they are connected) in test, but in exec they're removed and thus removing is allowed.

src/road_gui.cpp

@@ -586,7 +586,7 @@ struct BuildRoadToolbarWindow : Window {
 				break;
 
 			case WID_ROT_CONVERT_ROAD:
-				HandlePlacePushButton(this, WID_ROT_CONVERT_ROAD, GetRoadTypeInfo(this->roadtype)->cursor.convert_road, HT_RECT);
+				HandlePlacePushButton(this, WID_ROT_CONVERT_ROAD, GetRoadTypeInfo(this->roadtype)->cursor.convert_road, HT_RECT | HT_DIAGONAL);
 				this->last_started_action = widget;
 				break;
 
@@ -805,7 +805,7 @@ struct BuildRoadToolbarWindow : Window {
 					break;
 
 				case DDSP_CONVERT_ROAD:
-					Command<CMD_CONVERT_ROAD>::Post(GetRoadTypeInfo(this->roadtype)->strings.err_convert_road, CcPlaySound_CONSTRUCTION_OTHER, end_tile, start_tile, _cur_roadtype);
+					Command<CMD_CONVERT_ROAD>::Post(GetRoadTypeInfo(this->roadtype)->strings.err_convert_road, CcPlaySound_CONSTRUCTION_OTHER, end_tile, start_tile, _cur_roadtype, _ctrl_pressed);
 					break;
 			}
 		}

src/script/api/script_road.cpp

@@ -132,7 +132,7 @@
 	EnforcePrecondition(false, ::IsValidTile(end_tile));
 	EnforcePrecondition(false, IsRoadTypeAvailable(road_type));
 
-	return ScriptObject::Command<CMD_CONVERT_ROAD>::Do(start_tile, end_tile, (::RoadType)road_type);
+	return ScriptObject::Command<CMD_CONVERT_ROAD>::Do(start_tile, end_tile, (::RoadType)road_type, false);
 }
 
 /* Helper functions for ScriptRoad::CanBuildConnectedRoadParts(). */