[OSM-talk] [Fwd: Re: Proliferation of path vs. footway]

Norbert Hoffmann nhoffmann at spamfence.net
Thu Aug 13 22:59:48 BST 2009


David Earl wrote:

>So what you're saying is that
>
>- each editor and data consumer has to have its own set of national
>rules and defaults rather than defining them centrally (so inevitably
>they'll end up different);

The editors must have some way to set defaults, the consumers will get a
full dataset. So they must know the defaults plus the interpretation of the
tagger(!) *now* but not later.

>- we have to massively increase the amount of data we store by saying
>for every road that it is open 24 hours a day (because some aren't) and
>has a 44 tonne weight limit (or whatever it is by default in your
>country) except for the few cases where it isn't; all cycleways don't
>permit llama pack animals (because some in Peru do) and all motorways
>explicitly do or don't permit horse drawn vehicles.

The most common values (by highest count) can be left out from the *db* and
only be stored once. So yes, there must db-wide-defaults. 

>- we can't type a simple tag any more, we have to go via a menu or a
>form because there are so many of them. Every highway would have to
>carry maybe thirty or forty tags giving use cases,

Shure you can tag "cycleway" and nothing else, but you'll have tell the
editor once, what a cycleway means to you.

>and every time we
>realise we are missing a use case (say we discover motorways in Ecuador
>permit learner drivers to use them [please don't tell me this isn't the
>case - it's only an example]) we have to add tags to every other highway
>in the world to say that there learner drivers can't, otherwise we're
>assuming a default.

If you'll need to update any record in the table for this is a question of
design.

>- and that we have to update almost every way in the system already
why?

>and change every bit of software we already have
why?

Norbert "playing advocatus diaboli"





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