[OSM-dev] ways with 'spurs'

[Dan Moore]

imho, probably first thing to get straight is the purpose/context for these definitions, variously implied as being:
 - a logically correct model for rendering
 - a model that eases rendering
 - a model that fits with a layman understanding of what a road or street is
 - a model that is most database-space efficient

 - a model that gives highest database read/write speed
 - a model that is easiest to implement client-side
 - a model that is easiest to implement server-side
 - what the current database currently copes with
 - what the api currently copes with

to which could be added more, i'm sure, e.g. maybe... 
 - a model that holds logical road relationships necessary for providing good turn / continue directions in a navigation application
 - etc.

the uber-purpose being:
 - a model against which we can store data and unequivocally derive databases/systems that fulfil all of the (above/some-well-defined-list-of) purposes

and the definition of said purpose(s) being a pre-requisite. without that discussion will inevitably go somewhat in circles...

personally, i would say all efficiency/performance concerns must surely be subservient to data completeness/correctness concerns and can practically be tackled at an entirely different level.

hope that makes sense, it sort of does to me.  i think.
cheers, dan.

----- Original Message ----
From: 80n <80n80n at gmail.com>
To: Barry Crabtree <barry.crabtree at gmail.com>
Cc: dev at openstreetmap.org; Nick Whitelegg <Nick.Whitelegg at solent.ac.uk>
Sent: Monday, February 26, 2007 3:43:40 PM
Subject: Re: [OSM-dev] ways with 'spurs'

On 2/26/07, Barry Crabtree <barry.crabtree at gmail.com> wrote:
>
>
> On 2/26/07, Nick Whitelegg <Nick.Whitelegg at solent.ac.uk> wrote:
> > Sent by:        dev-bounces at openstreetmap.org
> > To:     dev at openstreetmap.org
> > cc:
> > Subject:        [OSM-dev] ways with 'spurs'
> >
> > >I've come across some ways that go:
> >
> > >   A -> B -> C -> B -> D
> >
> > >Shouldn't they be done as:
> >
> > >   A -> B -> D, with a separate way B -> C?
> >
[...]







 
____________________________________________________________________________________
Need Mail bonding?
Go to the Yahoo! Mail Q&A for great tips from Yahoo! Answers users.
http://answers.yahoo.com/dir/?link=list&sid=396546091