[Talk-ca] GeoBase import more questions and ideas

richard at weait.com richard at weait.com
Thu Jan 1 16:29:14 GMT 2009

Dale asked some things and Sam answered below:
>> I'm of the impression that there are:
>> a) a set of built in 'tags' that the rendering engine uses. (is there an
>> exhaustive list anywhere)

These should get you started.


> Seeing as how you were able to convert the raw GeoBase data into Garmin
> format, there got to be a way to convert that post-IMG file you created to
> OSM format, using what you already created.

Sam, this sounds like a Really Bad Idea.  Converting good data from the
source format into a proprietary, imperfectly reverse engineered format,
then into the open OSM format makes no sense to me.  The Geobase (and
other source) data is rich and diverse.  The OSM format is rich, diverse
and extensible.  The Garmin format is optimized for one use only; to work
on a Garmin handheld.

Why do you suggest that we handcuff the Geobase data by filtering it
through the Garmin format?  Why do you suggest that we poison OSM by
making it reliant on translation through an intermediate, proprietary

There are benefits to going the other way, and converting OSM data to use
on Garmin devices.  See the existing projects here, they already include
reference to the tool Dale uses, cGPSmapper and also to free tools.


>> Wouldn't the most sensible way to add information be to take the
>> original
>> SHPs and go from there? (including *all* of the database information).

That sounds like the way to go, Dale.  And that is in line with what the
TIGER import and other data imports have done, as far as I know.

> Since you already made up your own GeoBase2garminIMG conversion
> chart/list,
> it would really help if we could see this chart.

This doesn't apply at all for the Geobase conversion and import to OSM,
but I can see it being a helpful addition to displaying OSM data on a
Garmin.  Dale, would you consider Open Source-ing, and contributing your

> So far, as we saw Michel Gilbert has been able to;
> get the shape files; attach source tags; attach the OSM map feature, and
> import it.

Again, Bravo, Michel!  The border that you have converted and uploaded is
a big improvement.  Here it is, rendered, in Lake Ontario.  Notice the
previous US import shows the border as hugging the US coast line.

> The reason i suggest grabbing the data direct from the .mp file

Really bad idea.  See above.

> The DOWNSIDE of this 5 step process is that it DOES NOT keep the geobase

That sounds like a further, fatal flaw with the idea of converting through
the Garmin format.  How can future Geobase updates even be considered if
the NIDs / UUIDs are dropped?

Then Sam added:
> in response to the 2nd messages before i send this.
[ ... ]
> who else can also answer the question:  What is the Goal of this Project?

The wiki says it well, on the front page:

  OpenStreetMap creates and provides free geographic data such
  as street maps to anyone who wants them. The project was
  started because most maps you think of as free actually have
  legal or technical restrictions on their use, holding back
  people from using them in creative, productive, or
  unexpected ways.

The project is many different things to many different people.  There are
82,086 OpenStreetMap participants, as of 01 Jan 2009.  I've been fortunate
enough to meet a few hundred OSMers in the last two years.  Some of them

- cyclists who want great cycle maps that don't end at the town line or
state border.
- coders and developers who love making F/LOSS tools.
- entrepreneurs who (plan to) profit from reselling OSM data and services
built upon OSM.
- neighbourhood advocates who want to map the Business Improvement
District, save the local wetlands, or both.
- geography professionals who are intrigued by the F/LOSS approach to GIS
and the OSM tools.
- researchers who are interested in OSM as a source of data.
- data providers who wish to widen the reach of their data.
- entrepreneurs who want to put their company on the map.
- hardware enthusiasts who want to put a map on their PDA, phone, laptop,

I've never been able to predict in advance who would have questions about
what aspects of OSM, but most would ask about questions about:

- why use OSM compared to {some other online map}
- how to do a survey and contribute data.
- how to get started with the editors.
- how is data rendered.
- when does my contribution appear on the map.
- how to map their specific personal interest.

But then many people would have widely diverging interests that might
cover one or two of:

- how is distributed programming used in tiles at home.
- can OSM show historic maps.
- details of data structure in OSM.
- how to start developing for OSM.
- tracking things that move with OSM.
- OSM growth.
- how to use OSM to support an argument or cause.
- servers and bandwidth.
- using OSM with existing tool n.

> Where is the OSM specialty?
> The specialty is in the extra tagging, which is not available on any other
> map. Resulting in rendering which wont happen on anyother map.

That is part of it.  GIScience2008 was a revelation to me, as several GIS
professionals who had little direct experience with OSM recognized key
benefits of OSM and mentioned them in their presentations.

Free tagging is important and was recognized as an important feature of
OSM in James Campbell's presentation on Folksonomy and GIS at GIScience in
September 2008.  James outlined the freetagging / folksonomy aspect of OSM
and how it is combined with a smaller thesaurus of widely used tags.

Rendering is important, and the ability to customize the renderer is
important as well, but there is more to GIS than just rendered maps. 
Barbara Poore spoke at GIScience, as well.  She talked about maps that
aren't maps; like the spoken turn instructions from a navigation system. 
This is something that we can do with OSM as well.  Restricting OSM to
"just rendering maps" would prevent this, as other restrictions would
prevent other creative uses of OSM.

The one thing that makes OSM a valid option for so many different people,
for so many different purposes, is the freedom to be creative.  That
freedom is deliberate.  OSM contributors do wonderful and creative things
because that is explicitly allowed by the Open Source licenses of the OSM
tools and the CC / ODbL licenses of the data.

The OpenStreetMap banner that we use often at mapping parties may be the
best way to sum up the focus of OpenStreetMap during the development
cycle.  http://wiki.openstreetmap.org/wiki/Banner

It's fun.  It's free.  You can help.

Perhaps that can be amended for data consumers:

It's fun.  It's free.  It can help.

Best regards,

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