I don't really understand what this patch is trying to achieve. There is a patch by Thilo Hanneman (I'm attaching it for you) that makes it possible to directly render relations from the relations file, I think that is more useful - or don't I understand something here that you intend to achieve???
Felix, I had a closer look at the patch and got some questions. As far as I understand the patch it tries to connect all ways of a relation and tags these ways with a special mkgmap:gtype tag which is a summary of all attributes of the relation(?) The convertRelation method tries to connect all ways of a relation. The responsible addWayToListAndChainIfPossible method seems to care about oneway tags if a way is classified as road. I don't know if the handling of two connected ways in following order is correct: Way 1: road, oneway=yes Way 2: no road You will get one way tagged with oneway=yes although the 2nd way is no road. All new assembled ways are put to the waymap, but with a different id. The assembled way copies the original way id from the first way but for the way map a fake id is generated. Although it's working I think that's no good programming style. I am a bit surprised because I think that the patch creates at least one new way for each relation. Doesn't that mean that you have n overlapping ways in case you have n relations on the same way? Probably I don't understand it so could you please explain what happens if one way is contained in multiple relations? WanMil