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I'm using osm2po to import Open Street Map data. I want to get information about roundabouts. In the final SQL file I need to know if a road is part of a roundabout or not.

The only way to get this information in the SQL file is to change the clazz or flag value.

How can I get a different clazz value for roundabouts?

I have tried to change the configuration file but without any effect :

wtr.tag.junction.roundabout =    1, 77, 35

I never get 77 value in clazz column.

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you actually caught me on the wrong foot ;-)

junction=roundabout needs some (hard coded) extra handling with reference to the oneways. Because of this fact, I've mistakenly isolated it in an else-block where the configuration could not override it. This will be fixed in the next version. THX!!! Nevertheless, junction=roundabout is not a main-tag. It's an additional tag to e.g. highway=xxx. But if you need it as a road-clazz, you can declare it the way above. In this case you'll have to take the concurrent order into account. Meaning, you should give it precedence over highway-tags (see first parameter '1'). If you only need the information "this is a roundabout", use the wtr.allow...-tag instead.

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Can you give me a configuration example ? I try to add a flag on wtr.flagList = car, bike, foot, rail, ferry, roundabout and wtr.finalMask = car|roundabout. I also add allow/deny : wtr.allow.junction.roundabout = roundabout wtr.deny.junction = roundabout – user13226 Dec 3 '12 at 9:59
I try to remove residential road with wtr.deny.highway.residential = car (It works) but removing roundabout don't work with wtr.deny.junction.roundabout = car – user13226 Dec 3 '12 at 10:17
please read my answer above. in the current version the roundabouts will be swalled by an isolated else-block, so the confic can not override it. – Carsten Dec 3 '12 at 18:40
Nevertheless, you're approach is almost correct. You'll need to expand the flagList (..., roundabout) and finally have to set wtr.allow.junction.roundabout = car. You do not need to set wtr.finalMask = ... | roundabout. If you need it urgently, please contact me via mail, so I can send you a current intermediate-version. – Carsten Dec 3 '12 at 18:50
I see this is working now. Is there anyway to tell from the geojson response, where in the roundabout you are? In other words, can I count the exits in the roundabout so I know what exit I want to take during navigation? – maw269 Jul 21 '14 at 22:34

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