[mkgmap-dev] special case where splitting fails without a log message

Tue May 25 13:00:36 BST 2021

Sorry - sea.zip!

On Tue, 2021-05-25 at 12:36 +0100, Ticker Berkin wrote:
> Hi Gerd
> 
> I'm getting very confused by this. When I build with my trunk (some
> filter order changes + a few others), I see a whole lot more that
> JOSM
> shows. It and your 6324001.img just show a central bit. Looking with
> GPSMapEdit with "Highlight Polygon Contours". I also see areas where
> all islands are inverted.
> 
> I'll undo my trunk changes and look again.
> 
> Does JOSM have self-intersection checking?
> 
> Was the gpx trace hi-res (30bit) and then this kept when generating
> the
> osm. If not, then I'd expect problems.
> 
> Ticker
> 
> 
> On Tue, 2021-05-25 at 11:18 +0000, Gerd Petermann wrote:
> > Hi Ticker,
> > 
> > I didn't investigate the details. I've created the osm data by
> > converting a gpx back to osm. I guess in the original input
> > duplicate
> > points are identical. I found more such cases where parts are
> > removed.
> > 
> > Gerd
> > 
> > 
> > ________________________________________
> > Von: mkgmap-dev <mkgmap-dev-bounces at lists.mkgmap.org.uk> im Auftrag
> > von Ticker Berkin <rwb-mkgmap at jagit.co.uk>
> > Gesendet: Dienstag, 25. Mai 2021 12:51
> > An: Development list for mkgmap
> > Betreff: Re: [mkgmap-dev] special case where splitting fails
> > without
> > a log message
> > 
> > Hi Gerd
> > 
> > OK - I've reproduced this. Is split-failed.osm self-intersecting?
> > I'm
> > not sure how to tell from Josm, but it looks like it isn't. I get
> > the
> > messages from shapeSplitter because it thinks it is and then the
> > result
> > is not good - as expected.
> > 
> > I'll investigate more.
> > 
> > Ticker
> > 
> > 
> > On Tue, 2021-05-25 at 10:04 +0000, Gerd Petermann wrote:
> > > Hi Ticker,
> > > 
> > > while looking at the problems with sea I found this case where
> > > ShapeSplitter removes a small part of an island from a self
> > > -intersecting polygon in res 24.
> > > Compiled with mkgmap from trunk, default style and no options.
> > > 
> > > Look at 67.6742611, 14.6783525
> > > 
> > > Found this with some check code that compares the area of the
> > > original polygon with that of sum of the parts.
> > > 
> > > Gerd
> > > _______________________________________________
> > > mkgmap-dev mailing list
> > > mkgmap-dev at lists.mkgmap.org.uk
> > > https://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
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