[Talk-ca] jsmart09's diary (canvec/ geobase discussion)

Sat Feb 6 04:27:54 GMT 2010

Cool,
feel free to post your notes on this talk-ca list, its always helpfull
to see other peoples views,
perhaps you can describe the python sticking point you had?
Perhaps others on this list can help?

Cheers,
Sam

On 2/5/10, JOHN SMART <smartowka at rogers.com> wrote:
> Hello Sam
>
> Yes I took an initial look at this stuff back in
> November or so but got stuck at a python problem. Taking another look at it
> now. I decided to try to write a few notes in my diary to record my
> learning experience, mostly for my own benefit at this time. I had not
> realised at first that it is a public diary but I did see that later.
>
> At this point I am learning, with a view to contributing some to the
> map. Eventually I will probably put some Canvec data in and improve
> some of the NB mapping (roads) that are there. If I have any questions
> I'll be sure to ask. Probably if I do stick some data in I will ask for
> people to review it to be sure I am doing the "right" thing.
>
> I have also browsed talk-ca a bit and there is much more I could learn in
> there I'm sure. I see your name in there a lot :)
>
> John
>
>
>
> ________________________________
> From: Sam Vekemans <acrosscanadatrails at gmail.com>
> To: Talk-CA OpenStreetMap <talk-ca at openstreetmap.org>
> Sent: Fri, February 5, 2010 9:06:15 PM
> Subject: [Talk-ca] jsmart09's diary (canvec/ geobase discussion)
>
> Hi, Just forwarding this message,
> It looks like we have someone interested in helping solve the CanVec.Geobase
> Hydrography delema :-)
>
>
> jsmart09's diary2010-02-04
>
> Today I have looked through the Canvec documentation, which is here:
> http://geogratis.cgdi.gc.ca/geogratis/en/collection/28954.html
> In particular, the Data Product Specifications
> http://ftp2.cits.rncan.gc.ca/pub/canvec/doc/CanVec_product_specifications_en.pdf
> and the Feature Catalogue:
> http://ftp2.cits.rncan.gc.ca/pub/canvec/doc/CanVec_feature_catalogue_en.pdf
> I want to understand these so that I can understand the rules files that Sam
> Vekemans has set up.
> Incidentally Geobase or Canvec? From what I can see Geobase is an
> initiative, to bring in data from multiple authorities. There is a
> variety of types of geo data. Canvec is basically the NTS topo map data
> but it has been reformatted / remodelled. New editions of Canvec are
> brought out, apparently every 6 months. We are onto edition 4 for NB at
> least for Fredericton area. The actual spatial data rarely seems to
> change and some parts are just as out of date in the newest edition
> (well actually they're more out of date!).
> NRN (National Road Network) has been incorporated into Canvec so
> there seems to be no difference in the data whether you get roads from
> Canvec or from NRN files.
> How to figure out what SHP file some entities / objects are in? Two
> letter code indicates general theme e.g. HD is hydrography, TR is
> transportation, TO is toponymy. Within the theme, there is a 7-digit
> code that indicates the entity type (what I'd think of as "object
> class"). E.g. 1480009 is the generic code for a Waterbody. Geometry
> (point, line, area) is split out into separate SHP files. So we have
> e.g.
> 021g15_4_0_HD_1480009_2.shp for:
> NTS tile 021G15
> Edition 4
> Version 0
> HD for hydrography
> 1480009 for waterbody objects
> 2 for area geometry
> Inside this SHP file there are all the waterbody objects for the area of
> 021G15.
> To encode the particular types of waterbody object there are further
> 7 digit codes, stored as the value of the CODE attribute. E.g. a CODE
> 1480272 is an "unknown / non-isolated" waterbody. A 1480092 is a
> "liquid waste, isolated" waterbody (i.e. a sewage holding pond)
> Hydrography: I thought it might be simple to get lakes and rivers
> out of Canvec, but some of the data is a bit strange. In 021G15 I have
> Mactaquac Lake and a big chunk of the St John River as the same area
> object. In Edition 3 it all had the name "Mactaquac Lake". Edition 4
> has removed the name. Likewise for the Oromocto River, a bunch of lakes
> adjacent to the river are all bundled into the same area object as the
> river.
> So how does Toporama -
> http://atlas.nrcan.gc.ca/site/english/maps/topo/map?mapsize=1150%201350&lat=45.85204497&long=-66.48944242&mapxy=2170329.14209+130644.561916&scale=5000000&feature_na=Oromocto+River&location1=13&unique_key=0c803390849c20c3b25c26ef7b645fbd&searchstring=oromocto%20river&entity=RIV&layers=fapfeature+nodata_ntdb_50k%20north_arrow%20other_features%20roads%20hydrography%20boundary%20builtup%20vegetation%20populated_places%20railway%20power_network%20manmade_features%20designated_areas%20water_features%20water_saturated_soils%20relief%20contours%20toponymy%20contour&urlappend=%26unique_key%3D0c803390849c20c3b25c26ef7b645fbd%26map.layer[textzoom03]%3DFEATURE+POINTS+2169671.31541+142309.976588+END+TEXT+%22Oromocto%2BRiver%22+END%26map.layer[textzoom46]%3DFEATURE+POINTS+2169671.31541+142309.976588+END+TEXT+%22Oromocto%2BRiver%22+END%26map.layer[lineresultzoom0]%3DDATA+fap_rivers%26map.layer[lineresultzoom1]%3DDATA+fap_rivers%26map.layer[lineresultzoom2]%3DDATA+fap
> _rivers%26map.layer[arrowzoom03]%3DFEATURE+POINTS+2169671.31541+142309.976588+END+END
> manage to get nice-ish looking lake and river names? Answer: there
> are TO (toponymy) theme point objects which have been digitized
> someplace inside the waterbody. As I mentioned above the waterbody
> could encompass multiple lakes and rivers. There is no relationship at
> all between the toponymy objects and the waterbodies.
> TO objects seem to have a generic theme number 1580009. Each object
> also has a CODE but its value always seems to be 1580010, for all the
> names I've looked at. There is an additonal attribute, CONCISECODE, and
> this is the one which differentiates e.g. French Lake (the lake,
> CONCISECODE=150) from French Lake (the hamlet, CONCISECODE=80).
> Actually if you look at the Feature Catalogue you can see that 80 is an
> "unincorporated area).
> How does OSM deal with area names? It seems it's all free and easy
> and varies depending on your mood. I looked at a lake or two in Maine
> and the area objects had no names but there were point names, like
> Canvec has. I also looked at a couple of lakes in Switzerland and saw
> that they had names as attributes of the lake edges. The Osmarenderer
> seems to pick up those attributes for display as names (if you zoom in
> far enough...) (Which raises another topic: where are the rules for the
> renderer? If I knew that, I could figure out what attributes are useful
> to include and what names to give them.. I think).
> Back to the Canvec data. If I want to use the hydrography, I just
> don't like the approach of the unrelated point objects. I'd prefer to
> make the name an attribute of the area object. That would mean I had to
> split up those humungous waterbodies into separate lakes and rivers.
> More work. Should I do it the simple way first then make another pass
> later to improve? Seems like the better approach.
> Maybe tomorrow I shall take another look at Sam Vekeman's rules
> files with a view to running the shp-to-osm.jar app to generate some
> .osm from one or two .shp files. Then I'll look at those in e.g. GM.
> I'll get a feel for what attribution the .osm is going to have. I
> should try to find whether there is any accepted standard for
> attribution for Canada at least.
> Question (to myself, rhetorical!): do we want to
> Posted by jsmart09 at Fri, 05 Feb 2010 02:51:03 +0000 in English (English)
> ________________________________
>
> Comment from acrosscanadatrails at Sat, 06 Feb 2010 01:04:33 +0000
> Hi, I've emailed the talk-ca at openstreetmap.org list, and copied your
> message, please join the list, as im sure others would be interested to
> hear from you.
> Cheers,
> Sam Vekemans
> acrosscanadatrails at gmail.com
>
>
>
> Twitter: @Acrosscanada
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> Skype: samvekemans
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> @Acrosscanadatrails
>

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