Method EstimateDestinations

src/station_gui.cpp:1527–1575

* Estimate the amounts of cargo per final destination for a given cargo, source station and next hop and * save the result as children of the given CargoDataEntry. * @param cargo type of the cargo to estimate destinations for. * @param source Source station of the given batch of cargo. * @param next Intermediate hop to start the calculation at ("next hop"). * @param count Size of the bat

	 * @param dest CargoDataEntry to save the results in.
	 */
	void EstimateDestinations(CargoType cargo, StationID source, StationID next, uint count, CargoDataEntry &dest)
	{
		if (Station::IsValidID(next) && Station::IsValidID(source)) {
			GoodsEntry &ge = Station::Get(next)->goods[cargo];
			if (!ge.HasData()) return;

			CargoDataEntry tmp;
			const FlowStatMap &flowmap = ge.GetData().flows;
			FlowStatMap::const_iterator map_it = flowmap.find(source);
			if (map_it != flowmap.end()) {
				const FlowStat::SharesMap *shares = map_it->second.GetShares();
				uint32_t prev_count = 0;
				for (FlowStat::SharesMap::const_iterator i = shares->begin(); i != shares->end(); ++i) {
					tmp.InsertOrRetrieve(i->second).Update(i->first - prev_count);
					prev_count = i->first;
				}
			}

			if (tmp.GetCount() == 0) {
				dest.InsertOrRetrieve(StationID::Invalid()).Update(count);
			} else {
				uint sum_estimated = 0;
				while (sum_estimated < count) {
					for (CargoDataSet::iterator i = tmp.Begin(); i != tmp.End() && sum_estimated < count; ++i) {
						CargoDataEntry &child = **i;
						uint estimate = DivideApprox(child.GetCount() * count, tmp.GetCount());
						if (estimate == 0) estimate = 1;

						sum_estimated += estimate;
						if (sum_estimated > count) {
							estimate -= sum_estimated - count;
							sum_estimated = count;
						}

						if (estimate > 0) {
							if (child.GetStation() == next) {
								dest.InsertOrRetrieve(next).Update(estimate);
							} else {
								EstimateDestinations(cargo, source, child.GetStation(), estimate, dest);
							}
						}
					}

				}
			}
		} else {
			dest.InsertOrRetrieve(StationID::Invalid()).Update(count);
		}
	}

	/**
	 * Build up the cargo view for PLANNED mode and a specific cargo.