Shortest path between two OSM nodes

[HumamHelfawi]

I want to compute shortest path between OSM node 1765878706 & 1765878672. Using OSRM, I am getting this result:

Why the shortest path was not simply like this:

Any hint is much appreciated.

[danpat]

You're seeing a manifestation of #4465

When you supply a coordinate that is equidistant from several edges, the one chosen to start the route on will be somewhat random.

When there are one-ways involved, this may force a seemingly unnecessary detour, as in your case. The edge being chosen is the south-bound one, and there is no other way to go.

There are two possible fixes here:

1. You workaround the issue by slightly moving your start coordinate in the desired direction, or by using the bearings= parameter to filter out the southbound candidates. This can be done on a case-by-case basis, but isn't easy to do for the general case.
2. Someone implements multi-start routing in our core routing algorithms, so that all equidistant snapping points are considered as starting candidates. This is a much larger effort.

[SiarheiFedartsou]

Point 2 seems to be implemented in #5953