[Xastir] $PGRMW waypoint support

[Jason KG4WSV]

On Thu, Oct 22, 2009 at 2:56 PM, Curt, WE7U <archer at eskimo.com> wrote:

> We already send out "$GPWPL" strings to an attached GPS under
> certain circumstances.  I believe it was tied into the distance
> parameter for audio alerts

Yep, I remember that because I found the waypoint code grepping
through the source, but couldn't figure out how to turn it on.  You
had to tell me. (:

> so you get waypoints posted to your GPS within
> that radius.  Good enough?

I haven't used in in a while, so forgive me if I'm remembering wrong,
but IIRC it only plots a generic waypoint (pretty much identical
behavior to D7/00), which is certainly helpful.

With the Garmin specific $PGRMW sentence, you can supplement this
basic waypoint with a custom icon, altitude, and status text in the
waypoint comment.  (And it is supplementing, as it only updates an
existing waypoint.)

Again, assuming I've got everything straight, the code you posted in
your next message is a bit misnamed, as it creates an NMEA waypoint,
not a Garmin specific one.

What I'm envisioning is a) an update to the GPS interface to include a
"this device understands garmin $PGRMW sentences", and b) add a new
function to call after create_garmin_waypoint().  Hmm, I guess I'd add
"rename create_garmin_waypoint() to create_nmea_waypoint()" in there,
too.

-Jason
kg4wsv