Routing issue – local GraphHopper builds route through fields and river, while GH Maps shows correct road

[Ma_Sza]

Hi,
I’m using GraphHopper 10 (local build) with the following profile configuration:

profiles:
  - name: car
    encoder: car
    weighting: custom
    custom_model_files:
      [
        model_car.json
      ]
  - name: no_motorway_car
    encoder: car
    weighting: custom
    custom_model_files:
      [
        model_no_motorway_car.json
      ]
  - name: no_toll_motorway_car
    encoder: car
    weighting: custom
    custom_model_files:
      [
        model_no_toll_motorway_car.json
      ]
  - name: truck
    encoder: car
    weighting: custom
    custom_model_files:
      [
        model_truck.json
      ]

vehicles:
  - name: car

model_car.json

{
  "speed": [
    {
      "if": "true",
      "limit_to": "car_average_speed * 0.95"
    },
    {
      "if": "urban_density == CITY",
      "multiply_by": 0.6
    },
    {
      "if": "urban_density == RESIDENTIAL",
      "multiply_by": 0.85
    },
    {
      "if": "road_class == MOTORWAY || road_class == TRUNK || road_class == PRIMARY || road_class == SECONDARY || road_class == TERTIARY || road_class == UNCLASSIFIED || road_class == RESIDENTIAL",
      "multiply_by": 0.93
    }
  ],

  "distance_influence": 0
}

I’ve also tried to add
{
“if”: “road_class == SERVICE”,
“multiply_by”: 0.5
},
{
“if”: “road_class == TRACK”,
“multiply_by”: 0.1
}

my local instance routes through fields and a river (no visible road),
while the same coordinates on graphhopper.com/maps follow the correct nearby road

It seems that my local profile behaves differently from the default “car” used on GH Maps.
Could you please confirm what default configuration GH Maps uses for the car profile,
and what might cause this routing mismatch?

my route:

GH route:

[MeirR]

Hi @Ma_Sza

In addition to speed statements you need to use priority statements to specifically exclude roads that cars aren’t allowed in, currently you allow for any roads to be used.

Add this above your speed speed block, it says if the roads have no car access allowed, give them 0 priority, i.e. never use them.

 "priority": [
    { "if": "!car_access", "multiply_by": "0" }
  ]

Take a look at the default car profile here: https://github.com/graphhopper/graphhopper/blob/master/core/src/main/resources/com/graphhopper/custom_models/car.json

By the way I see one of your profiles is named no motorways, you can similarly exclude motorways with

    { "if": "road_class == MOTORWAY, "multiply_by": "0" }