Function findAllUsableTrackInNetwork

src/OpenLoco/src/Vehicles/Routing.cpp:615–668

    // 0x004A2FE6 & 0x004A3462
    template<typename FilterFunction>
    static void findAllUsableTrackInNetwork(LocationOfInterestQueue& additionalTrackToCheck, const TrackNetworkSearchFlags searchFlags, const LocationOfInterest& initialInterest, FilterFunction&& filterFunction, RoutingResults& results)
    {
        const auto [trackEndLoc, trackEndRotation] = World::Track::getTrackConnectionEnd(initialInterest.loc, initialInterest.tad()._data);
        auto tc = World::Track::getTrackConnections(trackEndLoc, trackEndRotation, initialInterest.company, initialInterest.trackType, 0, 0);

        if (!tc.connections.empty())
        {
            for (auto c : tc.connections)
            {
                uint16_t trackAndDirection2 = c & World::Track::AdditionalTaDFlags::basicTaDWithSignalMask;
                LocationOfInterest interest{ trackEndLoc, trackAndDirection2, initialInterest.company, initialInterest.trackType };
                if (results.reachableLocs.tryAdd(interest))
                {
                    if (!filterFunction(interest))
                    {
                        findAllUsableTrackPieces(additionalTrackToCheck, searchFlags, interest, filterFunction, results);
                        additionalTrackToCheck.push_back(interest);
                    }
                }
            }
        }
        else
        {
            results.hasDeadEnd = true;
        }

        if ((searchFlags & TrackNetworkSearchFlags::excludeReverseDirection) == TrackNetworkSearchFlags::none)
        {
            // odd logic here clearing a flag in a branch that can never hit
            auto nextLoc = initialInterest.loc;
            auto& trackSize = World::TrackData::getUnkTrack(initialInterest.tad()._data);
            nextLoc += trackSize.pos;
            if (trackSize.rotationEnd < 12)
            {
                nextLoc -= World::Pos3{ World::kRotationOffset[trackSize.rotationEnd], 0 };
            }

            const auto rotation = World::kReverseRotation[trackSize.rotationEnd];
            auto tc2 = World::Track::getTrackConnections(nextLoc, rotation, initialInterest.company, initialInterest.trackType, 0, 0);
            for (auto c : tc2.connections)
            {
                uint16_t trackAndDirection2 = c & World::Track::AdditionalTaDFlags::basicTaDWithSignalMask;
                LocationOfInterest interest{ nextLoc, trackAndDirection2, initialInterest.company, initialInterest.trackType };
                if (results.reachableLocs.tryAdd(interest))
                {
                    if (!filterFunction(interest))
                    {
                        findAllUsableTrackPieces(additionalTrackToCheck, searchFlags, interest, filterFunction, results);
                        additionalTrackToCheck.push_back(interest);
                    }
                }
            }
        }
    }

    constexpr size_t kSignalHashSetSize = 0x400;
    constexpr size_t kTrackModHashSetSize = 0x1000;