Examples For Customizable Routing - GraphHopper Directions API

In this blog post we’ll describe how custom profiles can be used and include real world examples.

How to

You can try the examples on GraphHopper Maps. Please note that currently only for car, small_truck, scooter, bike and foot the custom routing support is deployed. To customize a request you click on the “custom” icon. When editing the custom model try out Ctrl+Space for auto complete e.g. inside an if-statement. The basic structure of a custom profile is described in this documentation.

Safe Biking

Let’s start with a simple example from the previous post – it shows how to avoid primary roads:

{
 "priority": [{
   "if": "road_class == PRIMARY",
   "multiply_by": "0.1"
 }]
}

Other possibilities are for example to avoid roads with higher speed signs and prefer official bike network:

{
 "priority": [{
   "if": "max_speed >= 50",
   "multiply_by": "0.1"
 }, {
   "if": "bike_network == MISSING",
   "multiply_by": "0.9"
 }]
}

Avoid roads with max_speed greater than 50 km/h.

Avoid tunnels:

{
 "priority": [{
   "if": "road_environment == TUNNEL",
   "multiply_by": "0.01"
 }]
}

Ride slower through e.g. pedestrian or footway. Here 5 minutes instead of 4:

{
 "speed": [{
   "if": "road_class == PEDESTRIAN",
   "multiply_by": "0.7"
 }]
}

Cargo Bike

The normal bike profile allows routing over steps in cases where otherwise a long detour is made. But a bike used for deliveries or children cannot be carried and should never be routed over this and so you can exclude it with the road_class encoded value:

{
 "priority": [{
   "if": "road_class == STEPS",
   "multiply_by": "0"
 }]
}

Further exclusions like ‘too narrow roads’ are possible which is important for e.g. cargo bikes:

{
 "priority": [{
   "if": "max_width < 1.5",
   "multiply_by": "0"
 }, {
   "if": "road_class == PRIMARY",
   "multiply_by": "0.1"
 }]
}

Walking for Tourists

Increase preference of the official hiking network and accept greater detours. As you can see in the custom profile all roads marked with “foot_network=other” are avoided and so e.g. “foot_network=regional” is used.

{
 "priority": [{
   "if": "foot_network == MISSING",
   "multiply_by": "0.5"
 }]
}

Economically Driving

There are many ways to save fuel. One is to drive slower and another is to prefer shorter routes. See how the custom profiles can look:

{
 "speed": [{
   "if": "true",
   "limit_to": "110"
 }],
 "priority": [{
   "if": "road_class == MOTORWAY || road_class == SECONDARY",
   "multiply_by": "0.4"
 }]
}

Reduce max_speed for all roads and avoid motorways and secondary road.

Prefer shorter routes. Here the faster motorway is avoided. To do that you increase the distance_influence:

{
 "distance_influence": 120
}

The distance_influence is independent of the road properties and does not influence the ETA. The default is 70 in seconds per 1km. Let’s assume a route that takes 1000sec and is 10km long, then a value of 30 means that I would like to drive maximum 11km to reduce the travel time to 970sec, or drive max 12km to reduce it to 940sec.

Now to the area feature:

Avoid certain area like a city center where stop and go will cost a lot of fuel. For the area you can use a GeoJSON. Currently the areas are not displayed on the map you can use helper tools like geojson.io

Click on the image to calculate the route and paste the following profile:

{
 "priority": [{
   "if": "in_cottbus",
   "multiply_by": "0"
 }],
 "areas": {
   "cottbus": {
    "type": "Feature", 
    "properties": {},
    "geometry": { 
      "type": "Polygon", 
      "coordinates": [[
       [ 14.31, 51.75 ],
       [ 14.34, 51.75 ],
       [ 14.34, 51.77 ],
       [ 14.31, 51.77 ],
       [ 14.31, 51.75 ]
      ]]
    }
   }
 }
}

A powerful concept is to combine areas with arbitrary other conditions. E.g. you can prefer or avoid certain roads only in or outside of an area. The following example avoids the motorway only outside of the specified area:

{
 "priority": [{
   "if": "road_class == MOTORWAY && in_near_calau == false",
   "multiply_by": "0"
 }],
 "areas": {
  "near_calau": {
    "type": "Feature",
    "properties": {},
    "geometry": {
      "type": "Polygon",
      "coordinates": [[
        [ 13.84826, 51.6137 ],
        [ 13.9746, 51.61375 ],
        [ 13.97323, 51.82983 ],
        [ 13.84963, 51.83323 ],
        [ 13.84826, 51.6137 ]
      ]]
    }
   }
 }
}

Arbitrary combinations of conditions are possible like excluding motorways outside a specific area.

Truck

You can use custom profiles to give the car profile several “truck” attributes. First of all you should reduce the max_speed and the speed and increase the distance_influence like we did for the “economically driving”.

Further changes can be done like avoiding ferries:

{
 "priority": [{
   "if": "road_environment == FERRY",
   "multiply_by": "0.1"
 }, {
   "else_if": "road_class == RESIDENTIAL || road_class == TERTIARY",
   "multiply_by": "0.3"
 }, {
   "else_if": "road_class == TRACK",
   "multiply_by": "0"
 }]
}

Exclude ferries and tracks. And avoid smaller roads like residential and tertiary.

Now to the typical truck use cases like avoid toll, width or height limitations:

{
 "priority": [{
   "if": "toll == ALL || toll == HGV",
   "multiply_by": "0.1"
 }]
}

Consider more truck properties:

{
 "priority": [{
   "if": "hazmat == NO || hazmat_water == NO",
   "multiply_by": "0"
 }, {
   "if": "hazmat_tunnel == D || hazmat_tunnel == E",
   "multiply_by": "0"
 }, {
   "if": "max_width < 3 || max_weight < 3.5 || max_height < 4",
   "multiply_by": "0"
 }]
}

Here we exclude roads where hazmat=no (i.e. when our truck loads hazmat) and roads where max_width is smaller than 3m, max_weight is smaller than 3.5t or max_height is smaller than 4m. The hazmat encoded values, especially hazmat_tunnel, do still seldom occur in OSM data. Other properties could be axle_load and max_length.

Conclusion

As already mentioned this feature will strongly benefit from your feedback. So do not hesitate to share your experience, custom profiles or problems you are running into!

Happy custom routing!