Re: [Gpsbabel-misc] proximity alarm in Garmin waypoint files

[Robert L. <rob...@us...>]

Scout wrote:
> I've been told that ...
> 
> > Several of the newer Garmin receivers have a proximity alarm that if
> > your database had a 100m (or .1km) constant in that field, whenever
> > Garmin owners downloaded that file that proximity field in each
> > dashpoint record would be populated with the correct value. Currently
> > I modify every one manually.  What is neat is that when I enter within
> > 100 meters of a proximity waypoint, my GPS will alarm to let me know. 
> > Is this a possible feature to add?   
> 
> Do you know if this is true and if so, whether GPSBabel would support 
> this feature?

Some Garmins will do it and some don't.  Some have a max number of
points that they'll it for, and amongst the receivers that do it,
there seems to be a different number supported without any real way to
distinguish them.    

We have some plumbing for it, but GPSBabel has never really done
anything terribly ambitious with it.  There is some sketchy stuff in
mapsource.c for it and there's a bunch of code in jeeps (the garmin
serial/usb goop) for it, but I'm not sure that code in jeeps been
exercised so experience with that code makes me skeptical about it.
Looking at the Garmin protocol spec, there's a a completely different
protocol (sigh) for proximity waypoint transfer, yet there's an optional
"proximity" on most of the existing waypoint transfer types, so it's not
clear to me which is really necessary to support.  (If it's "merely"
plumbing it in to the existing protocols, support is likely trivial; if
it's doing the A400 stuff, it's likely to be a big pain.)

See also:
	http://groups.yahoo.com/group/gpsxml/message/831

If you can be specific in what you're looking for, I'm open to improving
this situation if I can find someone that knows how this should all work
and is willing to help exercise it.

RJL