[mkgmap-dev] [Patch v1] splitter: improve splitting with polygon file

Wed Mar 9 09:58:37 GMT 2016

Hi all,

as Andrzej pointed out (1) splitter r428 and older have a problem with

the --polygon-file option, the tiles written by splitter can contain too much data

outside of the polygon which later crashes mkgmap.

The attached patch should fix this without causing much changes in other use cases.

In general the resulting tiles should fit better into the given polygon now, but

of course I can't test all special cases.

Please try the binary from here with your data when you use  polygon(s) with

either the --polygon-file  or the --polygon-desc-file option:

http://files.mkgmap.org.uk/download/293/splitter.jar

@Andrzej: Please try with the default resolution 13.

When you use 14 instead of 13 you have 4 times more grid elements and therefore more

values to store and many more cases to test, with 16 it is 4*4*4 = 64 times more.

I saw good results with 13, res. 16 nearly kills my 8 GB machine.

I think you only need a higher resolution when the data contains extremely dense area,

means a single grid element contains much more than the desired max-nodes nodes.

ciao,

Gerd

(1) http://gis.19327.n5.nabble.com/problem-with-splitter-and-bounding-polygon-tt5868839.html
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