Function CmdBuildRoadWaypoint

src/waypoint_cmd.cpp:342–467

* Build a road waypoint on an existing road. * @param flags type of operation. * @param start_tile northern most tile where waypoint will be built. * @param axis orientation (Axis). * @param width width of waypoint. * @param height height of waypoint. * @param spec_class custom road stop class. * @param spec_index custom road stop id. * @param station_to_join station ID to join (NEW_STATIO

 * @return the cost of this operation or an error.
 */
CommandCost CmdBuildRoadWaypoint(DoCommandFlags flags, TileIndex start_tile, Axis axis, uint8_t width, uint8_t height, RoadStopClassID spec_class, uint16_t spec_index, StationID station_to_join, bool adjacent)
{
	if (!IsValidAxis(axis)) return CMD_ERROR;
	/* Check if the given station class is valid */
	if (static_cast<uint>(spec_class) >= RoadStopClass::GetClassCount()) return CMD_ERROR;
	const RoadStopClass *cls = RoadStopClass::Get(spec_class);
	if (!IsWaypointClass(*cls)) return CMD_ERROR;
	if (spec_index >= cls->GetSpecCount()) return CMD_ERROR;

	const RoadStopSpec *roadstopspec = RoadStopClass::Get(spec_class)->GetSpec(spec_index);

	/* The number of parts to build */
	uint8_t count = axis == AXIS_X ? height : width;

	if ((axis == AXIS_X ? width : height) != 1) return CMD_ERROR;
	if (count == 0 || count > _settings_game.station.station_spread) return CMD_ERROR;

	bool reuse = (station_to_join != NEW_STATION);
	if (!reuse) station_to_join = StationID::Invalid();
	bool distant_join = (station_to_join != StationID::Invalid());

	if (distant_join && (!_settings_game.station.distant_join_stations || !Waypoint::IsValidID(station_to_join))) return CMD_ERROR;

	TileArea roadstop_area(start_tile, width, height);

	/* Total road stop cost. */
	Money unit_cost;
	if (roadstopspec != nullptr) {
		unit_cost = roadstopspec->GetBuildCost(PR_BUILD_STATION_TRUCK);
	} else {
		unit_cost = _price[PR_BUILD_STATION_TRUCK];
	}
	StationID est = StationID::Invalid();
	CommandCost cost = CalculateRoadStopCost(roadstop_area, flags, true, StationType::RoadWaypoint, roadstopspec, axis, AxisToDiagDir(axis), &est, INVALID_ROADTYPE, unit_cost);
	if (cost.Failed()) return cost;

	Waypoint *wp = nullptr;
	CommandCost ret = FindJoiningWaypoint(est, station_to_join, adjacent, roadstop_area, &wp, true);
	if (ret.Failed()) return ret;

	/* Check if there is an already existing, deleted, waypoint close to us that we can reuse. */
	TileIndex center_tile = start_tile + (count / 2) * TileOffsByAxis(OtherAxis(axis));
	if (wp == nullptr && reuse) wp = FindDeletedWaypointCloseTo(center_tile, STR_SV_STNAME_WAYPOINT, _current_company, true);

	if (wp != nullptr) {
		/* Reuse an existing waypoint. */
		if (!HasBit(wp->waypoint_flags, WPF_ROAD)) return CMD_ERROR;
		if (wp->owner != _current_company) return CommandCost(STR_ERROR_TOO_CLOSE_TO_ANOTHER_WAYPOINT);

		ret = wp->rect.BeforeAddRect(start_tile, width, height, StationRect::ADD_TEST);
		if (ret.Failed()) return ret;
	} else {
		/* Check if we can create a new waypoint. */
		if (!Waypoint::CanAllocateItem()) return CommandCost(STR_ERROR_TOO_MANY_STATIONS_LOADING);
	}

	/* Check if we can allocate a custom spec to this waypoint. */
	auto specindex = AllocateSpecToRoadStop(roadstopspec, wp);