In a desktop application (not web), I need to find a way to compute and display a route by providing its start/end points with lat+lon, using routers such as GraphHopper, OSRM, or Valhalla.
Ideally, it should be on top of a live, zoomable map so the user can zoom in/out and move it around, but a static image is good enough so the user has a rough idea.
Is there a solution somewhere on the Net that could do this?
It is not easy to understand what you really mean, but I try it: If the region you are interested in is not too big you can run a local graphopper instance and access this instance via a browser locally.
You basically get what you can access on the internet via graphhopper maps . Here you can select different online background maps which are fetched via the network, zoom and set your starting point, the end point and via points via the mouse.
It is not possible to enter location names in the left panel in such a local installation. More information can be found on github. The installation requires a Java 17 runtime, a jar file, the OSM file of the region you are interested in, and adaptation of a configuration file. In this file you configure your required routing profile (car/bicycle or foot) and other settings.
You could use the bookmark feature of the browser in order to store an URLs of each required route.
