Country specific rules and default country / region or "--country-name=..."
Could the locator version be changed in such a way, that there are options to set the country and region using commandline/variables (and then drop all processing for country/region). I'm not sure if there is a difference between default country and actual country, but if there is then there should be different commands than the current --country-name= --country-abbr= area-name= This would be more than useful when using a geofabrik extract from a country or from a region (e.g. German Bundesland, or English/French state). That way it would save processing time, and be probably more correct (the very small errors in the geofabrik polygons defining the area, don't matter, as one does not expect to search for addresses outside of the country / region). (or is this implemented already, because on the trunk the --country=ABC seems not to be used, or worse I suspect that the --geonames-file=cities15000 from splitter and it's joining are used (which places addresses outside of the country, if close to a big city but belonging to another region -- or do I have to drop the geonames file if using locator branch?)
The locator branch is in an early alpha status. Such small optimizations can be added later on when the main problems are solved. WanMil
Could the locator version be changed in such a way, that there are options to set the country and region using commandline/variables (and then drop all processing for country/region). I'm not sure if there is a difference between default country and actual country, but if there is then there should be different commands than the current --country-name= --country-abbr= area-name=
This would be more than useful when using a geofabrik extract from a country or from a region (e.g. German Bundesland, or English/French state). That way it would save processing time, and be probably more correct (the very small errors in the geofabrik polygons defining the area, don't matter, as one does not expect to search for addresses outside of the country / region).
(or is this implemented already, because on the trunk the --country=ABC seems not to be used, or worse I suspect that the --geonames-file=cities15000 from splitter and it's joining are used (which places addresses outside of the country, if close to a big city but belonging to another region -- or do I have to drop the geonames file if using locator branch?) _______________________________________________ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
On 05.05.2011 19:35, WanMil wrote:
The locator branch is in an early alpha status. Such small optimizations can be added later on when the main problems are solved.
Do you consider this as small optimization? I think most people use / create maps from country extracts by geofabrik anyhow, so this is the first important step and save a lot of processing time / maybe even be enough for many people to find street addresses.
The locator branch is in an early alpha status. Such small optimizations can be added later on when the main problems are solved.
Do you consider this as small optimization?
Yes. If you have other numbers please post them. As long as splitter/mkgmap handles rect tiles only and not polygon shaped tiles it won't help (for most cases) to define a region which is assigned to all objects. So you save the country assignment only. And the processing time for this is neglegable compared to the other assignements of region and city. The reasons for this are very easy. 1. Counts A common tile contains data of a bit more than one country on average. But it contains up to some 1000 boundaries of other admin levels. So you have a lot of more queries to do for non country information. 2. Size of countries Most rectangular tiles cover one country only. Using the precompiled boundaries of the locator branch you get exactly one rectangular polygon for the single country and that's very low cost for retrieving all containing elements: it's just all.
I think most people use / create maps from country extracts by geofabrik anyhow, so this is the first important step and save a lot of processing time / maybe even be enough for many people to find street addresses.
Solve the main problems first (what to do with streets crossing from one city to another - cut them?, find a fast rtree like structure to perform the queries etc.) Then you can start to measure the performance and to think about optimizations. At least you can think about fine optimizations. And then you need someone who implements them: kind inviation for you to do so. WanMil
On 05.05.2011 23:01, WanMil wrote:
The locator branch is in an early alpha status. Such small optimizations can be added later on when the main problems are solved.
Do you consider this as small optimization?
Yes. If you have other numbers please post them.
As long as splitter/mkgmap handles rect tiles only and not polygon shaped tiles it won't help (for most cases) to define a region which is assigned to all objects. So you save the country assignment only.
And the processing time for this is neglegable compared to the other assignements of region and city. The reasons for this are very easy. 1. Counts A common tile contains data of a bit more than one country on average. But it contains up to some 1000 boundaries of other admin levels. So you have a lot of more queries to do for non country information.
2. Size of countries Most rectangular tiles cover one country only. Using the precompiled boundaries of the locator branch you get exactly one rectangular polygon for the single country and that's very low cost for retrieving all containing elements: it's just all.
I think most people use / create maps from country extracts by geofabrik anyhow, so this is the first important step and save a lot of processing time / maybe even be enough for many people to find street addresses.
Solve the main problems first (what to do with streets crossing from one city to another - cut them?, find a fast rtree like structure to perform the queries etc.) Then you can start to measure the performance and to think about optimizations. At least you can think about fine optimizations. And then you need someone who implements them: kind inviation for you to do so.
WanMil okay, thanks for the clarification, I thought the country selection takes more.
participants (2)
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Felix Hartmann -
WanMil