Points from routing wrong

eliasseverholt · July 24, 2020, 2:23pm

Hello!

I’m trying to call the API to get a route as a Polyline using points. The problem is that if I select for it to give me the points in the form of encoded points they get wrong quickly. However, when I wish to get it in latlng pairs it works great. But I want it in encoded points since it’s more efficient that way. If you aren’t understanding where I am coming from see the picture below!
Untitled|592x500
As you can see, it gives a rather good line until it decides to take a left and just leave. I’ve had it working a couple of months ago but now it just quits on me. Does anyone know how I can solve this?

Kind regards,
Elias

karussell · July 24, 2020, 3:15pm

Please use the correct decoding method. E.g. in JavaScript:

github.com

graphhopper/directions-api-js-client/blob/master/src/GHUtil.js#L27



    for (var prop in args) {
        if (args.hasOwnProperty(prop) && args[prop] !== undefined) {
            argsInto[prop] = args[prop];
        }
    }

    return argsInto;
};

GHUtil.prototype.decodePath = function (encoded, is3D) {
    var len = encoded.length;
    var index = 0;
    var array = [];
    var lat = 0;
    var lng = 0;
    var ele = 0;

    while (index < len) {
        var b;
        var shift = 0;

and Java:

github.com

graphhopper/graphhopper/blob/master/web-api/src/main/java/com/graphhopper/http/WebHelper.java#L54


*/
public class WebHelper {
   public static String encodeURL(String str) {
       try {
           return URLEncoder.encode(str, "UTF-8");
       } catch (UnsupportedEncodingException e) {
           throw new RuntimeException(e);
       }
   }

   public static PointList decodePolyline(String encoded, int initCap, boolean is3D) {
       PointList poly = new PointList(initCap, is3D);
       int index = 0;
       int len = encoded.length();
       int lat = 0, lng = 0, ele = 0;
       while (index < len) {
           // latitude
           int b, shift = 0, result = 0;
           do {
               b = encoded.charAt(index++) - 63;
               result |= (b & 0x1f) << shift;

eliasseverholt · July 24, 2020, 3:41pm

Hello!

I used online decoders such as google’s own decoder and that happened. Is there a seperate decoder for graphhopper?

eliasseverholt · July 24, 2020, 5:14pm

Update: I seem to have the same issue using google’s directions API. Will update if I find a solution.

eliasseverholt · July 27, 2020, 4:57pm

Solution has been found! Apparently it responded with a string where it used double backslashes ("\") instead of 1 backslash (""). Solution was just to replace “\” with “” and the problem was then solved!

system · October 25, 2020, 4:57pm

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