Requirement to detect Left/Right driving countries

[marq24]

to solve GIScience/openrouteservice#389

In OSM oneway cycleways are handled quite badly - at the end of the day the info cycleway:left=lane (or similar) requires to know the general driving direction of the country (in which the way is located) in order to determine the possible driving direction (for a bike).

We can either ignore "left" or "right" info - and let cyclist ride in "any direction" - or we need to detect the actual country via some bounding boxes (https://www.rhinocarhire.com/Car-Hire-Blog/August-2009/Which-Countries-Drive-on-the-Left,--a-Handy-Guide.aspx) and then based on the country we can implement the correct possible direction.

This issue is already present in the original GH code - so it's not a "self made" problem - IMHO the use of left and right in OSM tagging is fundamental wrong approach - but for sure we can not fix/adjust that... So the only correct solution will be to detect the country...

In order to save performance we can do that ONLY , if the way contain any left/right tags...

[rabidllama]

There is code available for checking if a way crosses a border, so that could probably be refactored to be more generic and then reused in the sided-ness check. My thought logic would be to remove the reference to the country file from the borders ext_storage within the app.config and then make it a global property. If a different file is needed for the borders, then it can be overridden in the ext_storage config area. Initially, the system would have to first check to see if the way was within a bbox of countries that represent a left-side driving, and if it is, then do the slower checks to find out if it is actually within a left-side country. If this is the case, an extra tag could be added to the way (e.g. left-side:true) which can then be used by graph builders.

...
CountryUtils.addSideTag(way);
...
if (way.hasTag(CountryUtils.LEFT_SIDE_TAG) && way.getTag(CountryUtils.LEFT_SIDE_TAG)) {
  // handle as left side driving
} else {
  // handle as right side driving
}

Alternatively, the methods for determining if it is a left side could be called when needed and the return value used to direct the code.

if (CountryUtils.determineDrivingSide(way) == DrivingSide.LEFT) {
    // handle left side driving
} else {
    // handle as right side
}

[aoles]

[aoles]

Driving side on ways could be resolved during preprocessing in a similar fashion as coutry/timezone processing.

[MichaelsJP]

This could be part of osm-transform. Create the respective left-right per country dataset and prepare the tags accordingly. No need to bloat ORS with routing, unrelated preprocessing. https://github.com/GIScience/osm-transform