Method updateWaterMotion

src/OpenLoco/src/Vehicles/VehicleHead.cpp:2834–3014

0x00427C05 Input flags: bit 0 : commandedToStop bit 1 : isLeavingDock Output flags: bit 16 : reachedDock bit 17 : reachedADestination

    // bit 16 : reachedDock
    // bit 17 : reachedADestination
    WaterMotionFlags VehicleHead::updateWaterMotion(WaterMotionFlags flags)
    {
        Vehicle train(*this);
        Vehicle2* veh2 = train.veh2;

        // updates the current boats position and sets flags about position
        auto tile = TileManager::get(veh2->position);

        SurfaceElement* surface = tile.surface();

        if (surface != nullptr)
        {
            auto waterHeight = surface->water();
            if (waterHeight != 0)
            {
                if (surface->isIndustrial())
                {
                    surface->setIsIndustrialFlag(false);
                    surface->setGrowthStage(0);
                }
                surface->setIndustry(IndustryId(0));
                surface->setType6Flag(true);
            }
        }

        auto targetSpeed = 5_mph;
        if (stationId == StationId::null)
        {
            if ((flags & WaterMotionFlags::isStopping) == WaterMotionFlags::none)
            {
                if (!veh2->has73Flags(Flags73::isBrokenDown))
                {
                    targetSpeed = veh2->maxSpeed;
                }
            }
        }

        if (targetSpeed == veh2->currentSpeed)
        {
            veh2->motorState = MotorState::coasting;
        }
        else if (targetSpeed < veh2->currentSpeed)
        {
            veh2->motorState = MotorState::coasting;
            auto decelerationRate = 1.0_mph;
            if (veh2->currentSpeed >= 50.0_mph)
            {
                decelerationRate = 3.0_mph;
            }
            veh2->motorState = MotorState::braking;
            auto newSpeed = std::max(veh2->currentSpeed - decelerationRate, 0.0_mph);
            veh2->currentSpeed = std::max<Speed32>(targetSpeed, newSpeed);
        }
        else
        {
            veh2->motorState = MotorState::accelerating;
            veh2->currentSpeed = std::min<Speed32>(targetSpeed, veh2->currentSpeed + 0.333333_mph);
        }