[OSM-talk] Abandon all ways: a polemic

Raphaël Jacquot sxpert at sxpert.org
Tue Mar 20 16:04:14 GMT 2007


obviously this was ment to the list, duh :D

Laurence Penney a écrit :
> Frederik Ramm wrote:
>> But a quick note about the "polemic" and your suggestion to only use 
>> segments. Basically, at the very low end of the database, having ways as 
>> ordered sequences of nodes does pretty much what you say.
> 
> The "ways as node sequences" data model is an interesting one, but 
> still flawed by ways representing something not particularly useful. 
> There's still that sticky issue that the number of nodes per way is 
> arbitrary. Such arbitrariness, I feel quite strongly, is a bad feature 
> of a data model. Are all data models equally good, as long as an ideal 
> app can cope with them?

the definition of a way is typically in the GIS world

* goes from one intersection to another intersection *

whoever says "the common definitions from the GIS world don't apply to
us because <blah>" is mistaken.

they represent topology at the most lower level, that is you can use
that way to go from a point to another point without intesecting with
another way.

now, this definition implies that this may be different from a street.

a street is composed of a number of ways, and ways composing that street
may have different navigation rules applied to them.

for instance, a street may be 2-way for most of it's lenght, except for
a little bit in the middle where it's either one way, forbidden except
to non motorized vehicle, access requires permission which is handled by
some device (automatic or manual bollards) or whatever else us, stupid
humans can think of to piss off other humans.

now. I'd like a proper explanation of why you feel a way shouldn't have
a arbitrary number of nodes in it's composition.





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