[Live-demo] 5.0 Beta 4 Status - Space

[Hamish]

Daniel wrote:
>>> For pgRouting Qucikstart I have to either download a smaller
>>> bbox of Denver area for pgRouting, or we could make the area
>>> smaller in general, and it will also decrease the size of
>>> pgRouting.

it seems the pgRt version is about 4x as big as the original
OSM postgis DB. does that copy all OSM ways or just the roads?
apparently topology is not cheap :)


Hamish:
>> can the pgRouting postgis db population step be done
>> specifying a limiting bounding box?

Daniel:
> Well, pgRouting takes the downloaded sample data of OSM and
> calculates network topology and then loads it into a
> database. There is possibility to specify a bounding box, so
> the easiest would be to just download a smaller extent of OSM.

? is or is not the possibility to specify a bounding box when
calculating topology and loading it into the database?


> I actually would like to avoid this, because now it's more
> convenient: if the OSM extent changes for the whole LiveDVD
> this also changes the sample data of pgRouting.
...
>> should we extract a smaller bbox just for use by the pgRouting
>> install script? A sluggish demo is probably not what you wish
>> to show off :)
>
> It's not sluggish even with a smaller extent. I find it rather
> hard to use for example with QGIS, when you want to load the
> whole OSM data. It is a bit too big for a LiveDVD in my
> opinion.

oh ok, I see what you mean. Too big for qgis not pgRouting.
(so we need to work to make qgis more efficient ;)
 

>> here is a visual version of the city-wide bbox I used:
>> http://www.openstreetmap.org/?box=yes&bbox=-105.2147,39.5506,-104.594,39.9139&mlat=39.74251&mlon=-104.9891
...
>
> Yes, I already made it smaller for the workshop, using just
> Denver downtown. Because it takes too long on weak notebooks
> to run the topology function.

bbox?


> Well, I'm OK with either way: download a smaller extent for 
> pgRouting only or decrease the size of the bbox in general.
> Who else is using OSM data on the LiveDVD? Is the data used
> for some map rendering?

Yes, GpsDrive renders OSM data from the PostGIS db on-the-fly
using mapnik with very pretty results. It is there to help
people find their way around the city and find a beer/bus stop,
which is why I at least wanted to show maps to the airport.

JOSM, Merkaartor editor and the Gosmore viewer from
OpenStreetMap will also use the data.

I am just trying the new gosmore version on the VM now (need to
run 'bzcat place.osm.bz2 | gosmore rebuild' first to rebuild
routing topology) 
It is quite neat in 3D mode (after rebuild search for 'Sheraton
Denver Downtown' to find the venue, still a work in progress but
it has made great advances since the last release. (middle click
to set start point, right click to set destination point for
routing)

Gosmore seems usable with the whole-city loaded in. initial
topology generation takes about a minute or two but only has to
be run once. JOSM handles large datasets extremely well,
Merkaartor a little less so, but it's still pretty good.


Hamish