[Routing] generalized routing format

[Marcus Wolschon]

On Thu, 16 Oct 2008 12:12:13 +0100, "Robert (Jamie) Munro"
<rjmunro at arjam.net> wrote:

> Personally, I don't think OSM should be trying to do this in the
> abstract. I think that as people develop routing applications, they
> should develop their own formats and converters from OSM XML format,
> optimised to how their particular applications work. As routing
> applications evolve, they could copy ideas and formats from each other.
> I don't think we should try to invent a format that is targeted at a
> particular market.

A binary-format that is indexed and directly usable can open the
door to many new tools. It is not trivial to write and not everyone
is capable of defining one. You make it sound like a trivial step
but it takes quite a bit more then a single developer can come up
with whereas writing a parser for it is very easy.
Also most formats used by existing
software are not documented, highly specific or require that one
database that this software is using.
Noone is forced to use the format we are discussing and it will
certainly not be perfect for every developer.

> It may be worth repackaging OSM XML and changesets as a binary format
> that is more compact, but routing applications would still need to index
> it before they could use it.

I don't agree here.
The existing xml-format is already great for general interchange.
Having it zipped there is no need for a new format just to make
it smaller (It will probably not get any smaller then today).

> Certianly I don't think that OSM centrally should be splitting the data
> into "routing layers".

I strongly agree. A binary-format should not loose any information
that may be usefull to an application.


Marcus