Re: [Geotools-gt2-users] Building a connected graph with OSM data / Splitting LineStrings at their intersections

[Michael B. <mic...@gm...>]

Hello

> 2) Split the linestrings in a seperate method and still build the graph with
> the LineStringGraphGenerator (code taken from here:
> http://n2.nabble.com/Splitting-LineStrings-at-their-intersection-td1941502.html
> http://n2.nabble.com/Splitting-LineStrings-at-their-intersection-td1941502.html

I'm not sure if this is relevant to your problem (I haven't used the
graph code in geotools) but to split your LineStrings at intersections
you could try the following JTS trick (courtesy of Martin Davis's
presentation at 2007 FOSS4G conference

Collection lines = ...  // your line strings
Geometry mls = geomFactory.buildGeometry(lines);  // create a MultiLineString
Point mlsPt = geomFactory.createPoint(mls.getCoordinate());  // get an
arbitrary point on a line
Geometry nodedLines = mls.union(pt);  // union the MultiLineString
with the point

This has the (almost magical) effect of noding all of the line intersections.

Hope this helps

Michael