[mkgmap-dev] overlays file for POIs

Mon Jan 18 14:18:12 GMT 2010

Hi Felix, Steve,

On Mon, Jan 18, 2010 at 03:00:06PM +0100, Felix Hartmann wrote:
> rcn_ref=10 [0x02 resolution 24 continue]
> rcn_ref=10 [0x03 resolution 24] --- is identical to the line above and 
> will not work.

Is there any reason for this?

> No, the trick is not working, as the you cannot run "continue" for 
> asking the same value twice. The idea of continue was more that if you 
> have a single node tagged amenity=restaurant & amenity=hotel that 
> neither is dropped (so you find both via the search function), or that 
> if a line is tagged higwhay=residential & railway=rail both will be 
> rendered/included in the map.

Could the "continue" allow multiple matches for the same set of keys?
If the "continue" is already in widespread use, we could avoid breaking
compatibility by introducing a "continue_same" keyword.

> > Ultimately, I would like to see something like this:
> >
> > (rcn_ref % 100 / 100) = 1 [symbol for '1__' continue]
> > (rcn_ref % 10 / 10) = 1 [ symbol for '_1_' continue]
> > (rcn_ref % 10) = 1 [ symbol for '__1' ]
> >
> > You might need to prefix these rules with rcn_ref=*.
> >    
> Well that would be nicer. If you integrate these regex operators, maybe 
> you could come up with a conversion for units (mph --> kph) too.

Actually, now that you mention regex (quite different from the arithmetics
that I suggested above), you should be able to do something like this:

rcn_ref=* & rcn_ref~'.*1..' [symbol for '1__' continue]
rcn_ref=* & rcn_ref~'.*1.' [symbol for '_1_' continue]
rcn_ref=* & rcn_ref~'.*1' [symbol for '__1' continue]
and for leading zeroes
rcn_ref=* & rcn_ref > 9 & rcn_ref~'.*0.' [symbol for '_0_' continue]

> It would be enough if:
> distance=125miles could be seperated into distance=125 
> distance:unit=miles for further processing.

OK, this could be doable by setting some variables to what is matched
by the regexp (think of $1, $2 et al of Perl and other languages).

	Marko