Last week, I trundled round the Red Course at the Clifton Country Park
Permanent Orienteering Course. As I approached each of the posts and
plaques, my mobile phone went "beep" and showed me which control I
should go to next. At the end, I have a full list of controls visited,
distances travelled and splits.  Getting the "beep" was (to me)
surprisingly and encouragingly accurate - the furthest distance away was
about 10m and the closest about 2m.

I could do something very similar with controls drawn at home, with
nothing in the terrain at all. So, in principle, you could set up a
complete training exercise (or competition) without putting any kites
out, so long as your mobile can pick up GPS signals in the terrain.

OK, so how did all that happen ?

First, I installed a Swedish app (Hippsomapp) onto my Android mobile, at
the massive cost of £3.97. This seems to be supported by a helpful chap
called Ulf, and a forthcoming version may include a couple of things I
asked for.

Next, I created a JPG of the POC map (by printing to PDF and converting
to JPG). And then I asked Eddie for an OCAD GPX export of the courses
(from his OCAD 11).

I transferred both these files to appropriate places on my phone, and
then imported the courses into the app. Almost ready to go ... now for
the most important bit.

Before you can do anything, you have to "calibrate" the map. ie. place
two points on it accurately with GPS coordinates. One way is to go stand
there and tell the phone where you are. Another way might be to try to
home in using Google Earth or Streetmap or suchlike, and try to position
a couple of significant corners or junctions. But, far better and
easier, if your base map has been "geo-referenced", is to simply pick
the coordinates of the two furthest-apart controls out of the OCAD 11
export.

And you're all set up. You simply pick a map, pick a course, stand next
to the Start control and tell the app to start. With this app, you can
have the map on display (so there's no actual need for a paper map,
though I'd think paper is far more convenient). And if you want more,
the app will tell you exactly where you are on that map.

As we speak, Eddie is working his way through MDOC's map library
geo-referencing our maps. I believe other club librarians are doing the
same. This is a non-trivial process which obviously needs to be done
accurately - ask Eddie for the details, but the purpose is to include in
the map file its actual position in the world, and the method is to
place the map against a known base (eg. OS data) and nudge as many
points as you need to get a good fit. The maps done so far have all been
re-shaped slightly as a result.

GPS technology has already transformed mapping, and route analysis. Here
it is offering virtual dibbing, and indeed, virtual controls. Anyone
interested in discussing next moves ?

John