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Handle Traffic Sign Alerts

Handle traffic sign alerts

This tutorial shows how to handle traffic sign alerts.

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There are various types of traffic sign alerts, all of them are point alerts, representing that there's a traffic sign around the alert location.

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void AlertObserver::onAlertInfoUpdated(const tn::drive::models::v1::AlertInfo& alertInfo)
{
    const auto& aheadAlerts = alertInfo.alerts_ahead;
    for (const auto& alert : aheadAlerts.point_alerts) 
    {
        // following types are speed limit alerts:
        // tn::drive::models::v1::AlertType::BeginOvertaking
        // tn::drive::models::v1::AlertType::EndOvertaking
        // tn::drive::models::v1::AlertType::ProtectedOvertakingExtraLane
        // tn::drive::models::v1::AlertType::ProtectedOvertakingExtraRight
        // tn::drive::models::v1::AlertType::ProtectedOvertakingExtraLeft
        // tn::drive::models::v1::AlertType::LaneMergeRight
        // tn::drive::models::v1::AlertType::LaneMergeLeft
        // tn::drive::models::v1::AlertType::LaneMergeCenter
        // tn::drive::models::v1::AlertType::RoadNarrows
        // tn::drive::models::v1::AlertType::SharpCurveLeft
        // tn::drive::models::v1::AlertType::SharpCurveRight
        // tn::drive::models::v1::AlertType::WindingRoadStartingLeft
        // tn::drive::models::v1::AlertType::WindingRoadStartingRight
        // tn::drive::models::v1::AlertType::BeginOvertakingTrucks
        // tn::drive::models::v1::AlertType::EndOvertakingTrucks
        // tn::drive::models::v1::AlertType::LateralWind
        // tn::drive::models::v1::AlertType::GeneralWarningSign
        // tn::drive::models::v1::AlertType::RiskOfGrounding
        // tn::drive::models::v1::AlertType::GeneralCurve
        // tn::drive::models::v1::AlertType::EndOfAllRestrictions
        // tn::drive::models::v1::AlertType::GeneralHill
        // tn::drive::models::v1::AlertType::AnimalCrossing
        // tn::drive::models::v1::AlertType::IcyConditions
        // tn::drive::models::v1::AlertType::SlipperyRoad
        // tn::drive::models::v1::AlertType::FallingRocks
        // tn::drive::models::v1::AlertType::LeftFallingRocks
        // tn::drive::models::v1::AlertType::RightFallingRocks
        // tn::drive::models::v1::AlertType::TramwayCrossing
        // tn::drive::models::v1::AlertType::CongestionHazard
        // tn::drive::models::v1::AlertType::AccidentHazard
        // tn::drive::models::v1::AlertType::PriorityOverOncomingTraffic
        // tn::drive::models::v1::AlertType::YieldToOncomingTraffic
        // tn::drive::models::v1::AlertType::CrossingWithPriorityFromRight
        // tn::drive::models::v1::AlertType::PedestrianCrossing
        // tn::drive::models::v1::AlertType::Yield
        // tn::drive::models::v1::AlertType::BeginNoEngineBrake
        // tn::drive::models::v1::AlertType::EndNoEngineBrake
        // tn::drive::models::v1::AlertType::NoIdling
        // tn::drive::models::v1::AlertType::TruckRollOver
        // tn::drive::models::v1::AlertType::BeginLowGear
        // tn::drive::models::v1::AlertType::EndLowGear
        // tn::drive::models::v1::AlertType::UrbanArea
        // tn::drive::models::v1::AlertType::Embankment
        // tn::drive::models::v1::AlertType::TwoWayTraffic
        // tn::drive::models::v1::AlertType::UnevenRoad
        // tn::drive::models::v1::AlertType::MaxSpeed
        // tn::drive::models::v1::AlertType::BicycleCrossing
        // tn::drive::models::v1::AlertType::YieldToBicycles
        // tn::drive::models::v1::AlertType::FloodArea
        // tn::drive::models::v1::AlertType::HumpBridge
        // tn::drive::models::v1::AlertType::STurns
        // tn::drive::models::v1::AlertType::WindingRoad
        // tn::drive::models::v1::AlertType::RailwayCrossing
        // tn::drive::models::v1::AlertType::TrafficLight
        const auto type = alert.basic.type;

        // each alert item has a unique identifier, can be used to match alert updates
        const auto id = alert.basic.id;

        showAlertIconOnMap(id, type, alert.point.location);
    }
}

Steep grade alerts

Steep grade alerts are traffic sign alerts with additional information.

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void AlertObserver::onAlertInfoUpdated(const tn::drive::models::v1::AlertInfo& alertInfo)
{
    const auto& aheadAlerts = alertInfo.alerts_ahead;
    for (const auto& alert : aheadAlerts.steep_grade_alerts) 
    {
        // following types are speed limit alerts:
        // tn::drive::models::v1::AlertType::SteepHillUpwards
        // tn::drive::models::v1::AlertType::SteepHillDownwards
        const auto type = alert.basic.type;

        // each alert item has a unique identifier, can be used to match alert updates
        const auto id = alert.basic.id;

        // slope grade percent is greater than 7%
        if (alert.severity == tn::drive::models::v1::Severity::Critical)
        {
            showAlertIconOnMap(id, type, alert.point.location);
        }
        // slope grade percent is greater than 3% and less equal to 7%
        else if (alert.severity == tn::drive::models::v1::Severity::kMedium)
        {
            showHintIconOnMap(id, type, alert.point.location);
        }
    }
}