[mkgmap-dev] [Patch] Faster BoundaryGrid

Thu May 3 21:12:14 BST 2012

Hi Gerd,

I also prefer solution 1.

WanMil

> Hi WanMil,
>
> you are right, the patched code is a bit slower for the normal case.
> I see two solutions:
> 1) We don't allow directories in the zip file. With this restriction we can
> simply stop searching if the wanted bnd file is not found instead of
> traveling through thousends of entries.
> We can alarm the user when we find a directory structure within the zip.
> 2) We save the list that is created in LocationHook.init() and use it as a
> parm for the BoundaryGrid
> constructor.
>
> I'd prefer option 1, what do you think?
>
> Gerd
>
>
> GerdP wrote
>>
>> Hi WanMil,
>>
>> attached is a small patch which drastically improves BoundaryGrid for
>> tiles that contain mostly sea. I found such a tile in south-america, and
>> the patched version is>  10 times faster.
>> It contais a large part of the pacific, and BoudaryGrid searches the
>> boundary zip file for
>>> 5000 different *.bnd files, most of them do not exist in your
>>> bounds_20120401.zip , so the
>> code in BoundaryUtil searches through all elements of the zip file to find
>> out that it doesn't exist.
>>
>> The patch creates a HashSet first with the  available files and calls the
>> load routine only for
>> those that exist.
>>
>> Gerd
>>   http://gis.19327.n5.nabble.com/file/n5680180/BoundaryGrid.java.patch
>> BoundaryGrid.java.patch
>>
>
>
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