[mkgmap-dev] is_in filter

Mon Feb 6 22:45:18 GMT 2017

Hi
First option sounds better, but if nobody can code it by now (sorry, I'm 
not dev1eloper) second option can be a good start point. Probably a 
combination of rules of the second type could get a similar effect: 
!is_in_landuse_residential() & !is_in_landuse_retail() [blablabla...]

El 06/02/17 a las 20:55, Gerd Petermann escribió:
> Hi Carlos,
>
> okay, I thought about this for a while. We need quite a lot of new code for this, so I think
> the user interface should be as flexible as possible.
> If we want to support a style function like is_in(<exp>)
> where <exp> can be something like
> landuse=residential
> or more complex stuff like
> landuse=forest | natural=wood
> In short, I think it should support more or less all Tag_tests including regular expressions
> and combined expressions. A complete style rule could look like this:
> building=* & !is_in(landuse=residential | landuse=retail)   [0x13 resolution 24]
> Those Tag_tests are used to filter the enclosing areas (closed ways, multipolygon-relations).
>
> I have no idea how to code the part that parses the style file.
> Is someone volunteering to code these changes?
> I think about a new class IsInFunction in package uk.me.parabola.mkgmap.osmstyle.function
> which would call an eval(element) method for each enclosing element. The eval method
> should return true / false.
>
> I'd like to code the needed methods to find the enclosing elements in an efficient way.
>
> If nobody finds a way to code the above style changes
> I can code a style function with a much simpler syntax like this:
> is_in_<key><val>()
> e.g.
> is_in_landuse_residential()
> or
> is_in_natural_wood()
> The name of the function gives the test:
> The enclosing element must have a key <key> with the value <val>
>
> Complex tests like regular expressions would not work with this.
>
> Gerd
>
>
> ________________________________________
> Von: mkgmap-dev <mkgmap-dev-bounces at lists.mkgmap.org.uk> im Auftrag von Carlos Dávila <cdavilam at orangecorreo.es>
> Gesendet: Samstag, 4. Februar 2017 16:37:11
> An: Development list for mkgmap
> Betreff: Re: [mkgmap-dev] is_in filter
>
> Yes, I think that would work.
> I forgot to mention another use case. highway>residential which lies
> inside residential areas. They have typically maxspeed lower than
> outside residential areas, but are not correctly tagged in many cases.
> Proposed filter could be used to lower maxspeed for those ways.
>
> El 04/02/17 a las 16:18, Gerd Petermann escribió:
>> Hi Carlos,
>>
>> I see a performance problem if mkgmap has to evaluate that for each element.
>> I think it would be better to have a special tag like mkgmap:remove-if-in=<type>
>> which would tell mkgmap to find out if the object lies (completely) within a polygon
>> that has the given type. This can happen after processing all polygon elements.
>> The polygons with the given type(s) could be placed in a spatial index if performance impact
>> is too heavy.
>> Do you think that would work as well?
>>
>> Gerd
>>
>> ________________________________________
>> Von: mkgmap-dev <mkgmap-dev-bounces at lists.mkgmap.org.uk> im Auftrag von Carlos Dávila <cdavilam at orangecorreo.es>
>> Gesendet: Samstag, 4. Februar 2017 16:06:20
>> An: Development list for mkgmap
>> Betreff: [mkgmap-dev] is_in filter
>>
>> One matter that has been discussed several times on this list is the
>> need to remove buildings. While removing buildings is becoming
>> absolutely necessary in many cities, due to massive building imports, it
>> may be quite convenient to keep them at rural or low densely populated
>> areas. Would it be possible to have a filter to know if a building is
>> inside/outside an area tagged landuse=residential, so that a different
>> rendering may be applied. Ideally area size could be also evaluated.
>> Perhaps some logic currently existing in mkgmap, used to assign
>> addresses from bounds, could be reused.