Method SwitchToNextOrder

src/train_cmd.cpp:2679–2723

* Set the current vehicle order to the next order in the order list. * @param skip_first Shall the first (i.e. active) order be skipped? * @return True if a suitable next order could be found. */

	 * @return True if a suitable next order could be found.
	 */
	bool SwitchToNextOrder(bool skip_first)
	{
		if (this->v->GetNumOrders() == 0) return false;

		if (skip_first) ++this->index;

		int depth = 0;

		do {
			/* Wrap around. */
			if (this->index >= this->v->GetNumOrders()) this->index = 0;

			Order *order = this->v->GetOrder(this->index);
			assert(order != nullptr);

			switch (order->GetType()) {
				case OT_GOTO_DEPOT:
					/* Skip service in depot orders when the train doesn't need service. */
					if (order->GetDepotOrderType().Test(OrderDepotTypeFlag::Service) && !this->v->NeedsServicing()) break;
					[[fallthrough]];
				case OT_GOTO_STATION:
				case OT_GOTO_WAYPOINT:
					this->v->current_order = *order;
					return UpdateOrderDest(this->v, order, 0, true);
				case OT_CONDITIONAL: {
					VehicleOrderID next = ProcessConditionalOrder(order, this->v);
					if (next != INVALID_VEH_ORDER_ID) {
						depth++;
						this->index = next;
						/* Don't increment next, so no break here. */
						continue;
					}
					break;
				}
				default:
					break;
			}
			/* Don't increment inside the while because otherwise conditional
			 * orders can lead to an infinite loop. */
			++this->index;
			depth++;
		} while (this->index != this->v->cur_real_order_index && depth < this->v->GetNumOrders());

		return false;
	}
};

/* choose a track */