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As @Julien suggests (and I saw mentioned on the MapServer PR mentioned in comments by user30184) the best solution I've found is to use Dijkdtra's shortest path algorithm to find the longest shortest path between two nodes of degree 1 in the graph. As far as I can tell this was first proposed by Noah Veltman in his JavaScript code for Centreline placement. ...


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To improve efficiency, you could consider partitionning your problem: Decompose your area of interest into several zones, run the process on these zones and re-unite the result. For your case, you could consider decomposing the input square into 4, for each of them, select the land polygons intesecting them (with a spatial index why not), running the union/...


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A possible algorithm would be to extract the longest path of the skeleton, as a graph structure. This could be obtained by computing all shortest pathes between pairs of extreme leaf nodes (the ones with degree = 1) and keep the longest. (it assumes the skeleton has no cycle, which can happen when the input polygon has holes). This longest path has great ...


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So, I am publishing my new experimental improved function ST_CentraLAxisLongestLineFromVoronoiDiagrams, to try to make you a little happier :-), and for JAVA programmers to try to implement this approach based on the Voronoi Diagrams function. Create a function: CREATE OR REPLACE FUNCTION ST_CentraLAxisLongestLineFromVoronoiDiagrams( geom GEOMETRY, n integer)...


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Well, I've found a better way, WITHOUT USING GDAL JAVA! String lat = "-21.5"; String lon = "-49.5"; String dist = "10000"; String observerHeight = "0"; String targetHeight = "0"; String[] environments = null; File workdir = new File( workdirFolder ); String[] command = { ...


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By reading a couple of posts I found that there are some changes I have to make to do the conversion from SE to SLD : 1- <StyledLayerDescriptor xmlns="http://www.opengis.net/sld" xmlns:ogc="http://www.opengis.net/ogc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.opengis.net/sld ...


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