[mkgmap-dev] Turn restrictions with role=via ways

Tue Mar 18 15:56:48 GMT 2014

Hi Marko,

 > Anyway, the problem is that the U-turn restriction is ABCD
 > (A=from,B=via,C=via,D=to) while BCD (B=from,C=via,D=to) would suffice.

BCD restriction would be interpreted as turn-left restriction for cars 
coming from other road, which in most cases would be wrong. There is no 
shortcut for 4-points U-turn restriction.

I'm not sure, what are recommendation in OSM, but I think cgpsmapper is 
logical in its definition of restriction. Restriction should consist of 
nodes and ways between these nodes. There should be no guessing how to 
get from a node to next one.

OSM relation can include only a part of these data, for example 2 nodes 
and a way or 4 nodes. Any combination should be interpreted, converted 
to standard definition and used if can be stored in Garmin format.

-- 
Best regards,
Andrzej