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<body class='hmmessage'><div dir='ltr'>Hi WanMil,<br><br>I see that shapes created from precompiled sea are merged,<br>so it works in general. The problem remains that<br>for low resolutions I have to merge the shapes before the coords are <br>rounded. So, for low resolutions the shape merger stops<br>too early, because it will not create shapes with > 250 points<br>as long as we use the java.awt.geom.area to split those<br>shapes, and the merger doesn't know the result of the RoundCoordsFilter<br>which typically reduces the number of points drastically for low res.<br><br>Gerd<br><br><br><div>> Date: Thu, 16 Jan 2014 12:09:17 -0800<br>> From: gpetermann_muenchen@hotmail.com<br>> To: mkgmap-dev@lists.mkgmap.org.uk<br>> Subject: Re: [mkgmap-dev] shape merger in high-prec-coord branch<br>> <br>> Hi WanMil,<br>> <br>> yes, a few more shapes were be merged because of this change.<br>> Only if the parts go into different sub divisions they are not merged.<br>> I am not sure if that works for precompiled sea data, I'll <br>> verify that tomorrow.<br>> <br>> Gerd<br>> <br>> <br>> WanMil wrote<br>> > Hi Gerd,<br>> > <br>> > good! This is the first part of my idea.<br>> > Additionally I thought about what you have written as TODO: maybe better <br>> > merge here? I think when cutting multipolygons it often happens that <br>> > there are parts cut off that needn't be cut.<br>> > I have attached a screenshot of a sea tile where I have colored some <br>> > polygons in blue that could be merged to one big polygon. Maybe there is <br>> > an advantage that some of the small cuts do not disappear on lower zoom <br>> > levels because they belong to a bigger polygon.<br>> > <br>> > But I am not sure if that isn't already solved by your changes.<br>> > <br>> > WanMil<br>> > <br>> >> Hi WanMil,<br>> >><br>> >> please check the changes in r2970 reg. MultiPolygonRelation.<br>> >> Is this the change you had in mind?<br>> >><br>> >> Gerd<br>> >><br>> >> > Date: Wed, 15 Jan 2014 21:55:17 +0100<br>> >> > From: <br>> <br>> > wmgcnfg@<br>> <br>> >> > To: <br>> <br>> > mkgmap-dev@.org<br>> <br>> >> > Subject: Re: [mkgmap-dev] shape merger in high-prec-coord branch<br>> >> ><br>> >> ><br>> >> > > I think the artifacts are created by the rounding that happens<br>> >> > > when we convert from or to java.awt.geom.Area.<br>> >> ><br>> >> > Yes. After the multipolygon splitting only the first and the last<br>> >> point<br>> >> > of a common edge of two polygons can be a point that is added<br>> >> > artificially. It sounds possible to detect if it ca be removed.<br>> >> ><br>> >> > WanMil<br>> >> > _______________________________________________<br>> >> > mkgmap-dev mailing list<br>> >> > <br>> <br>> > mkgmap-dev@.org<br>> <br>> >> > http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev<br>> >><br>> >><br>> >> _______________________________________________<br>> >> mkgmap-dev mailing list<br>> >> <br>> <br>> > mkgmap-dev@.org<br>> <br>> >> http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev<br>> >><br>> > <br>> > <br>> > _______________________________________________<br>> > mkgmap-dev mailing list<br>> <br>> > mkgmap-dev@.org<br>> <br>> > http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev<br>> > <br>> > mp_merge.png (16K)<br>> > &lt;http://gis.19327.n5.nabble.com/attachment/5793366/0/mp_merge.png&gt;<br>> <br>> <br>> <br>> <br>> <br>> --<br>> View this message in context: http://gis.19327.n5.nabble.com/shape-merger-in-high-prec-coord-branch-tp5793093p5793368.html<br>> Sent from the Mkgmap Development mailing list archive at Nabble.com.<br>> _______________________________________________<br>> mkgmap-dev mailing list<br>> mkgmap-dev@lists.mkgmap.org.uk<br>> http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev<br></div> </div></body>
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