ルート上の交通状況を視覚化する

GeoPolyline routeGeoPolyline = route.getGeometry();
double outlineWidthInPixel;
Color polylineColor = Color.valueOf(0.051f, 0.380f, 0.871f, 1.0f);
Color outlineColor = Color.valueOf(0.043f, 0.325f, 0.749f, 1.0f);
MapPolyline routeMapPolyline = null;
try {

    // Below, we're creating an instance of MapMeasureDependentRenderSize. This instance will use the scaled width values to render the route polyline.
    // We can also apply the same values to MapArrow.setMeasureDependentTailWidth().
    // The parameters for the constructor are: the kind of MapMeasure (in this case, ZOOM_LEVEL), the unit of measurement for the render size (PIXELS), and the scaled width values.
    MapMeasureDependentRenderSize mapMeasureDependentLineWidth = new MapMeasureDependentRenderSize(MapMeasure.Kind.ZOOM_LEVEL, RenderSize.Unit.PIXELS, getDefaultLineWidthValues());

    // We can also use MapMeasureDependentRenderSize to specify the outline width of the polyline.
    outlineWidthInPixel = 1.23 * mapView.getPixelScale();
    MapMeasureDependentRenderSize mapMeasureDependentOutlineWidth = new MapMeasureDependentRenderSize(RenderSize.Unit.PIXELS, outlineWidthInPixel);
    routeMapPolyline = new MapPolyline(routeGeoPolyline, new MapPolyline.SolidRepresentation(
            mapMeasureDependentLineWidth,
            polylineColor,
            mapMeasureDependentOutlineWidth,
            outlineColor,
            LineCap.ROUND));

} catch (MapPolyline.Representation.InstantiationException e) {
    Log.e("MapPolyline Representation Exception:", e.error.name());
} catch (MapMeasureDependentRenderSize.InstantiationException e) {
    Log.e("MapMeasureDependentRenderSize Exception:", e.error.name());
}
mapView.getMapScene().addMapPolyline(routeMapPolyline);

// Returns a hashMap where the key is the zoom level and the value is the corresponding scaled width.
private HashMap<Double, Double> getDefaultLineWidthValues() {
    HashMap<Double, Double> widthsPerZoomLevel = new HashMap<>();
    // Here width value will remain 2.18 from 0.0 zoom level to 6.0.
    // From 6.0 the updated value 2.48 will be used.
    widthsPerZoomLevel.put(0.0, 2.18);
    widthsPerZoomLevel.put(6.0, 2.48);
    widthsPerZoomLevel.put(7.0, 2.78);
    widthsPerZoomLevel.put(11.0, 3.1);
    widthsPerZoomLevel.put(16.0, 3.15);
    widthsPerZoomLevel.put(17.0, 3.35);
    widthsPerZoomLevel.put(18.0, 3.78);
    widthsPerZoomLevel.put(19.0, 6.5);
    widthsPerZoomLevel.put(20.0, 10.2);
    widthsPerZoomLevel.put(24.0, 77.5);
    return scaleCurrentHashMap(widthsPerZoomLevel);
}

private HashMap<Double, Double> scaleCurrentHashMap(HashMap<Double, Double> currentValues) {
    for (Map.Entry<Double, Double> entry : currentValues.entrySet()) {
        entry.setValue(entry.getValue() * mapView.getPixelScale());
    }
    return currentValues;
}

// Retrieves the default widths of a route polyline and maneuver arrows from VisualNavigator,
// scaling them based on the screen's pixel density.
private HashMap<Double, Double> getDefaultLineWidthValues() {
    HashMap<Double, Double> widthsPerZoomLevel = new HashMap<>();
    for (Map.Entry<MapMeasure, Double> defaultValues : VisualNavigator.defaultRouteManeuverArrowMeasureDependentWidths().entrySet()) {
        Double key = defaultValues.getKey().value;
        Double value = defaultValues.getValue() * mapView.getPixelScale();
        widthsPerZoomLevel.put(key, value);
    }
    return widthsPerZoomLevel;
}

Section firstSection = route.getSections().get(0);
DynamicSpeedInfo dynamicSpeed = firstSection.getSpans().get(0).getDynamicSpeedInfo();

val firstSection = route.sections[0]
val dynamicSpeed = firstSection.spans[0].dynamicSpeedInfo

// This renders the traffic jam factor on top of the route as multiple MapPolylines per span.
private void showTrafficOnRoute(Route route) {
    if (route.getLengthInMeters() / 1000 > 5000) {
        Log.d(TAG, "Skip showing traffic-on-route for longer routes.");
        return;
    }

    for (Section section : route.getSections()) {
        for (Span span : section.getSpans()) {
            DynamicSpeedInfo dynamicSpeed = span.getDynamicSpeedInfo();
            Color lineColor = getTrafficColor(dynamicSpeed.calculateJamFactor());
            if (lineColor == null) {
                // We skip rendering low traffic.
                continue;
            }
            float widthInPixels = 10;
            MapPolyline trafficSpanMapPolyline = null;
            try {
                trafficSpanMapPolyline = new MapPolyline(span.getGeometry(), new MapPolyline.SolidRepresentation(
                                new MapMeasureDependentRenderSize(RenderSize.Unit.PIXELS, widthInPixels),
                                lineColor,
                                LineCap.ROUND));
            } catch (MapPolyline.Representation.InstantiationException e) {
                Log.e("MapPolyline Representation Exception:", e.error.name());
            } catch (MapMeasureDependentRenderSize.InstantiationException e) {
                Log.e("MapMeasureDependentRenderSize Exception:", e.error.name());
            }

            mapView.getMapScene().addMapPolyline(trafficSpanMapPolyline);
            mapPolylines.add(trafficSpanMapPolyline);
        }
    }
}

// Define a traffic color scheme based on the route's jam factor.
// 0 <= jamFactor < 4: No or light traffic.
// 4 <= jamFactor < 8: Moderate or slow traffic.
// 8 <= jamFactor < 10: Severe traffic.
// jamFactor = 10: No traffic, that is the road is blocked.
// Returns null in case of no or light traffic.
@Nullable
private Color getTrafficColor(Double jamFactor) {
    if (jamFactor == null || jamFactor < 4) {
        return null;
    } else if (jamFactor >= 4 && jamFactor < 8) {
        return Color.valueOf(1, 1, 0, 0.63f); // Yellow
    } else if (jamFactor >= 8 && jamFactor < 10) {
        return Color.valueOf(1, 0, 0, 0.63f); // Red
    }
    return Color.valueOf(0, 0, 0, 0.63f); // Black
}

// This renders the traffic jam factor on top of the route as multiple MapPolylines per span.
private fun showTrafficOnRoute(route: Route) {
    if (route.lengthInMeters / 1000 > 5000) {
        Log.d(TAG, "Skip showing traffic-on-route for longer routes.")
        return
    }

    for (section in route.sections) {
        for (span in section.spans) {
            val dynamicSpeed: DynamicSpeedInfo? = span.dynamicSpeedInfo
            val lineColor = getTrafficColor(dynamicSpeed?.calculateJamFactor())
                ?: // We skip rendering low traffic.
                continue
            val widthInPixels = 10f
            var trafficSpanMapPolyline: MapPolyline? = null
            try {
                trafficSpanMapPolyline = MapPolyline(
                    span.geometry, MapPolyline.SolidRepresentation(
                        MapMeasureDependentRenderSize(
                            RenderSize.Unit.PIXELS,
                            widthInPixels.toDouble()
                        ),
                        lineColor,
                        LineCap.ROUND
                    )
                )
            } catch (e: MapPolyline.Representation.InstantiationException) {
                Log.e("MapPolyline Representation Exception:", e.error.name)
            } catch (e: MapMeasureDependentRenderSize.InstantiationException) {
                Log.e("MapMeasureDependentRenderSize Exception:", e.error.name)
            }

            if (trafficSpanMapPolyline != null) {
                mapView.mapScene.addMapPolyline(trafficSpanMapPolyline)
                mapPolylines.add(trafficSpanMapPolyline)
            }
        }
    }
}

// Define a traffic color scheme based on the route's jam factor.
// 0 <= jamFactor < 4: No or light traffic.
// 4 <= jamFactor < 8: Moderate or slow traffic.
// 8 <= jamFactor < 10: Severe traffic.
// jamFactor = 10: No traffic, ie. the road is blocked.
// Returns null in case of no or light traffic.
private fun getTrafficColor(jamFactor: Double?): Color? {
    if (jamFactor == null || jamFactor < 4) {
        return null
    } else if (jamFactor >= 4 && jamFactor < 8) {
        return Color.valueOf(1f, 1f, 0f, 0.63f) // Yellow
    } else if (jamFactor >= 8 && jamFactor < 10) {
        return Color.valueOf(1f, 0f, 0f, 0.63f) // Red
    }
    return Color.valueOf(0f, 0f, 0f, 0.63f) // Black
}