Re: [Jts-topo-suite-user] Polygon union to kml

[Veit K. <ve...@la...>]

Just for your information, i found some problems.

#1 if polygons touch at one point only it´s failing. i made my square
polygons a tiny bit bigger so they overlap just a little - now it´s looks
fine in google earth.

#2 if there is a hole in the polygon it does not draw correct as kml. so i
will split these areas.

so it´s not the fault of the library. any hints for me would be nice, but i
think i will get it

best regards
 veit

2012/6/29 Veit Kötting <ve...@la...>

> Hi there,
>
> i´m quite new to JTS and i already like it very much :)
>
> i´m have lots of square geometries with gps coordinates from a weather
> radar. now i do the union.buffer(0) to make a polygon from the parts which
> belong together.
> it works fine.
>
> now i´m trying to write it to .kml and display it in google earth.
> it works if the polygon doesn´t get to complex.
>
> i think it fails if there are two squares only connected at the corner,
> not on the edge. and i think google earth depends on the correct order of
> coordinates to draw a polygon like it´s supposed to.
>
> if it fails, there are some lines connecting squares that are not supposed
> to be connected, mostly these corners where there is no contact between the
> edges are connected even if they are far away (i hope you understand, my
> english is not that good)
>
>
> so, is there another way to write a geometry to a .kml?
>
>
> this is part of my code:
>
> writer.writeStartElement("outerBoundaryIs");
>         writer.writeCharacters("\n");
>         writer.writeStartElement("LinearRing");
>         writer.writeCharacters("\n");
>
>         writer.writeStartElement("coordinates");
>
>         for (Coordinate point: coordinates) {
>         writer.writeCharacters(ConvertCoordToString(point.y) + "," +
>               ConvertCoordToString(point.x) + "," +
>                   "0.0" + "\n");
>         }
>
>
>         writer.writeEndElement(); // coordinates
>         writer.writeCharacters("\n");
>
>