One correction of existing route changes entire route

openrouteservice directions
1

Hi

I have a route from Osmand~ that I imported into the openrouteservice Web front-end. There I noticed a small portion of the route being off the road (for cars). When I move it onto the road, openrouteservice changes a large portion of the route. As I am not interested in a different route, is there a way to prevent “optimization”?

Thanks so much.

2

Hey,

yeah, importing is not really made for editing existing routes, wherever they come from.

The underlying issue here is that openrouteservice operates on a list of points that it should travel to, one after the other. The output, however, is a line that goes via these points, but may have a lot of intermediate points defining the line.

Think of a winding mountain path without intersections: openrouteservice calculates a route based on two points: the start in the valley and the end on the mountain.
The resulting route, however, will consist of way more points - basically, one at every place where the walking direction changes, even ever so slightly.

Importing a route then can work in two ways:

  • Visualize the imported route - which is what currently happens.
    Any dragging of the route then results in new points for a new route, and the large change you experience.

  • Re-calculate the route based on the imported points making up the route.
    For most routes, this will result in way too many via-points - openrouteservice only allows 50, but thinking back to the mountain path, you can see how there will probably be more than 50 direction-changes in there.

The tool would rather need the original list of waypoints which were used to calculate the imported route, which again only helps if the route was calculated using openrouteservice in the first place.

For this, using a tool like QGIS (a fully fleged GIS client) and the corresponding ORS plugin (ORS Tools) is probably way easier.

Best regards

3

Hi jschnell

Thank you for your detailled response.

As I am a newbie to routing tools, I’m unsure I understand you correctly. Are you saying that it is easier to either use QSIR with the corresponding plugin to correct the existing route or to use openrouteservice to recreate the route from scratch and import it into Osmand~?
There are certain areas (e.g. Capetown) where it is crucial that your route works as planned. I noticed that using Osmand~ to create a route and attach it to the roads is fairly error-prone. So I’m looking for means to create solid routes on the PC and import them into Osmand~.

Thanks so much for your help.

4

Hey,

I think it would be easier to recreate the route from scratch, and then import it, yes.

Whether you want to use QGIS or the web client for that is up to you.
Whereas QGIS is quite powerful and the ORS-plugin has gotten better and better, it is still less beginner-friendly than a web client.

Best regards

5

Thank you very much!

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