[Talk-ca] Canada WikiMAP - Tile numbering System

[Sam Vekemans]

Thanks Simon, copying to this talk page so everyone  is upto date.

>This could give something like:
20830100.zip - zip file containing...
20830100.img - overview map for 83-A,
>gmapsupp.img - actual download, which contains...
20830101.img through xx830116.img - the individual tiles for 083-A-01
through 083-A-16 (also available as seperate files incase someone wants to
compile their own gmapsupp.img).

By organizing all of the Canada maps, when they are converted into garmin
format.  I think it makes sence that we all stick to the same format.
This way, when we are downloading the maps to use, its just a matter of
swapping the different maps, and they will all align.

Using the GeoBase tile set its relatively easy to understand.
http://www.geobase.ca/geobase/en/browse.do?produit=cded&decoupage=50k&map=canada


   - We start with a '2' because '1' is that the rendered GeoBase Garmin IMG
   files are saved as, (the ibycus topo) so this way, we can easily swap the
   GeoBase Ibycus Topo, for the OSM Canada Topo mapset (Canada WikiMAP) ...
   (once its relitevely complete)...
      - Alternatively, if we were making the cycling map we would used a
         '3'.  or a bus route map using a '4'
         - We use the 3 digit number '001-117' (newfoundland to the top of
   the Yukon) and 120,340,560 for the north pole area.
   - each of the tiles are then broken down into 16 squares, and labled A-P
   so the numeric cross reference is 01-16
   - then again each tiles are broken down to numbers 01-16.
   - These small tiles are measured to be 1/2 degree latitude and 1/4 degree
   longitude.
   - So then this leaves room to further split the map to 16 and go as far
   down as you like.

What this allows for, is so then anyone can make a map and simply expand
their area to the nearest 1/4 degree, or 1/8, 1/16.  Usually the cities will
cover more tiles, however by breaking it down.  it makes it easier to lign
up, when adding in other tiles that other people have made.

An update:
I have figured out how to get the whole Canada WIkiMAP onto 1 download and
viewable map. (using XAPI)  What i am doing is combining these larger tiles
areas, so that there are 10 or less, which will make it easier to extract
the data from OSM.
Also, (thanks to mungewell) its possable to get the topo's from the Shuttle
Radar Topography mission (SRTM) rendered for all of canada, this data will
be broken down into rectangles and measuered to the nearest degree or 1/2 or
1/16th. .. this way, for whatever areas that are not yet covered, the user
will simply be able to swap back and fourth from the (geobase) government
map to the OSM Canada Map. ... the aim of course, is to have OSM become the
most detailed map technically available.  Its almost there already.
Once i get the whole Canada WikiMAP loaded, with the OSM data and a start on
the Topo, i can add in the Unofficial Trans Canada trail, and have a few
GeoBase tiles available as a separate tiles download, covering Sault Ste.
Marie, Ontario for the opening of a new paviion.  (Hopefully) this will
create a larger Buzz about this, and spir more people to be out there on the
trails and mapping as they go.

Wow, with thoughts to add in the TTC routes too, and the heights of the CN
Tower... ya thats awesome.  Yup, the limits are really our imagination, and
the technical knowhow, which odds are someone somewhere might be working on
it. . its just a matter of building and tweeking and ....learning.

Happy Mapping,
Sam Vekemans
Across Canada Trails

P.S. As always... none of my work is set in stone, so if you have questions,
feel free to ask :)
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