Hi Felix,
reg. the idea of "cutting out overlaps": I guess it would consume quite a lot of CPU and it would heavily increase the img size because we would have to write many more points. Think of a shape for "place=village" with hundreds of holes for each building shape. Up to now we save the shape for the village and the shapes for the buildings. With cutting we have to calculate what remains of the village shape, this would be a very complex shape with many holes, so it would have many points. I don't think that would be a good idea. reg. sorting by size: I've not noticed any visible change in Basecamp or on my Oregon, so I don't think this is a solution. I looked at maps produced by Garmin and 1st got the impression that they are sorted by type, highest types coming first, but I also found exceptions. Don't know if this means that the order is not important or if there is a complex rules behind this. Gerd ________________________________ Von: mkgmap-dev <mkgmap-dev-boun...@lists.mkgmap.org.uk> im Auftrag von Felix Hartmann <extremecar...@gmail.com> Gesendet: Sonntag, 24. Juli 2016 21:40:47 An: Development list for mkgmap Betreff: Re: [mkgmap-dev] Option to output polygons in size order That is not really a good approach. Basecamp orders the polygons opposite to most gps devices. So it will still be broken. There is however a proper way to do - but that would be much much more complicated: Create a list of polygons that may not overlap (in the style-file). Then if mkgmap finds that 2 of these polygons do overlap - mkgmap should cut out the smaller polygon shape from the bigger. Basically the result of that approach would mimic how a Mapnik map looks in this case. Still the real solution however would be to fix the underlying OSM data. I have no clue how code and time intensive the "mimic Mapnik" approach would be, but everything else won't really solve much. On 24 July 2016 at 20:42, Gerd Petermann <gpetermann_muenc...@hotmail.com<mailto:gpetermann_muenc...@hotmail.com>> wrote: Hi Ticker, with the current algo the order is either "unpredictable" or the order in the input file (osm.pbf is typically sorted by id). This depends on the --preserve-element-order If I see this right this order will have an influence on the result of the so-called shape merger which tries to combine shapes with similar attributes. I still don't understand why the size should matter, but it should be easy to add a sort after the line shapes = mergedShapes; in MapBuilder.java I don't have the time today, so try on your own or wait a little for a patch . ________________________________ Von: mkgmap-dev <mkgmap-dev-boun...@lists.mkgmap.org.uk<mailto:mkgmap-dev-boun...@lists.mkgmap.org.uk>> im Auftrag von Ticker Berkin <rwb-mkg...@jagit.co.uk<mailto:rwb-mkg...@jagit.co.uk>> Gesendet: Sonntag, 24. Juli 2016 20:23:41 An: mkgmap-dev@lists.mkgmap.org.uk<mailto:mkgmap-dev@lists.mkgmap.org.uk> Betreff: Re: [mkgmap-dev] Option to output polygons in size order Hi Gerd Looking at the meaning of the sub-division, this looks like just the place to try and order the polygons by size! What governs the order they appear in at the moment? The size should be the full size of the individual polygon. Concerning the new thread "Why do we render place=island polygons in the default style", I have used "place=island & size_of() < 1000000" to get around the major problem but it seemed a bit arbitrary, and when I found other examples where, just sometimes, large polygons mask all features within I thought there must be a more general solution Ticker On Sun, 2016-07-24 at 00:05 -0700<tel:05%20-0700>, Gerd Petermann wrote: > Hi Ticker, > > Ticker Berkin wrote > > I'd understood and hoped that, for areas with the same level it > > rendered areas in file order, and I see on my device it > > overwriting, > > sometimes woods with island, sometimes the other way around, > > depending > > on, I presumed, the input ordering. I see the exactly the same > > overwriting effect zooming in or scrolling in any direction. > > > > What is the scale of the 'sub areas' you mention? > > I should have said sub division , and they have no specific scale. > They are used to group nearby elements, and they have several limits > like "not more than 255 points and not more than 255 lines in one sub > div" > For details see first the imgformat-1.0.pdf from Mechalas: > http://sourceforge.net/projects/garmin-img/files/OldFiles/imgformat.p > df/download > Other sources: > http://wiki.openstreetmap.org/wiki/OSM_Map_On_Garmin/IMG_File_Format > (which has more links at the end) > > Reg. the British Islands polygon: If I got that right this is the > very complex mp-relation > https://www.openstreetmap.org/relation/6038068 > (don't use the link, the thing is too complex) > It was added 2016-03-09 so maybe the problem is rather new and nobody > noticed it. I think it makes no sense to render that polygon, the > rules > in the default style should be changed to check the > area_size() for place=island so that large polygons are ignored. > I'll try to find a reasonable value. > > Gerd > > > > > > > -- > View this message in context: http://gis.19327.n5.nabble.com/Option-t > o-output-polygons-in-size-order-tp5878989p5879011.html > Sent from the Mkgmap Development mailing list archive at Nabble.com. > _______________________________________________ > mkgmap-dev mailing list > mkgmap-dev@lists.mkgmap.org.uk<mailto:mkgmap-dev@lists.mkgmap.org.uk> > http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev _______________________________________________ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk<mailto:mkgmap-dev@lists.mkgmap.org.uk> http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev _______________________________________________ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk<mailto:mkgmap-dev@lists.mkgmap.org.uk> http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev -- Felix Hartman - Openmtbmap.org & VeloMap.org Schusterbergweg 32/8 6020 Innsbruck Austria - ?sterreich
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