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<div dir="ltr">Hi Marko,<br><br><div>> >// also helps to produce a turn instruction when the main<br>> >// road bends sharply but the side road keeps close to the<br>> >// original heading<br>> <br>> Oh, that would seem to be applicable for a scenario where you have a <br>> grid of highway=residential, and among them a main road (say, <br>> highway=tertiary) that is going like zig-zag within the grid. Could it <br>> be that Garmin is not issuing a turn instruction in this case, when the <br>> main road consists of a single object (with a sharp turn in it)?<br><br>Do you have an example OSM id?<br><br>> <br>> AFAIR, there was another option for implementing support for <br>> through_route relations, in a case where a main road goes zig-zag <br>> through a village. Is it still present in the code base? Maybe it makes <br>> this case of --adjust-turn-headings redundant?<br><br>The evaluation of through-route relations is still in the code, I guess it still<br>works, but IIRC the tag is only rarely used.<br><br><br>I did a few more tests now (without --housenumbers for now).<br>I think the code for --adjust-turn-heading is somehow wrong, e.g.<br>if the calculated route is <br>entering the junction at node 1828873253<br><a href="http://www.openstreetmap.org/node/1828873253" target="_blank">http://www.openstreetmap.org/node/1828873253</a><br>from south going right will not not show a "turn right" instruction<br>when --adjust-turn-heading is used, but it does without the option.<br>Consequently, if the route goes straight on to way 171930600,<br>the instruction is "turn left onto Börtelsdamm" with and <br> no instruction without the option.<br><br>It seems that Garmin uses the "Continue on" instruction only on ramps.<br><br>Reg. ramps I found no positive effect with --adjust-turn-heading, I see the <br>same instructions but sometimes the calculated time is increased, probably <br>because the code increases the angle too much.<br>Maybe the option (and the code) is really obsolete since r3116 which introduced <br>the new routines for writing NOD data:<br><a href="http://www.mkgmap.org.uk/news/2014/03/19/announcement-version-r3116-is-a-major-u" target="_blank">http://www.mkgmap.org.uk/news/2014/03/19/announcement-version-r3116-is-a-major-u</a><br><br>Up to now I did my tests with real data, I'll try to create some test data to find out<br>if there is still a case where --adjust-turn-heading produces better instructions.<br><br>Gerd<br><br></div></div>
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