[drats_users] Map Downloader Question

[Dan Smith]

> Okay I was interpreting the interface incorrectly. The max zoom thing
> messed me up. If I select the 120 mile radius, it will draw a circle
> (with square edges due to the map tiles being square) 240 miles
> across centered on the coordinates I input. Is this correct?

The yes, although the value its prompting you for is diameter, not
radius.  I said "radius" in my previous email a couple times because I
wasn't thinking straight, but then went on to say diameter in my
explanation.  Anyway, the interface is asking you for diameter.

> The we click start and come back in an hour.

Yep.

> I assume map tiles of water should take less time to download (unless
> we are now plotting the favorite fishing holes) so it may not be that
> bad.

That's true, because a single-color square image should compress down
quite a bit.  However, there are two things to remember.  First, the
mapping protocol doesn't differentiate between two adjacent blue tiles,
so you have to download (and store) them each independently.  Second,
most of the delay you see is related to latency not throughput, so
downloading a bunch of "water" might not be much faster than a bunch of
"land".  It depends on your computer, internet connection, and how fast
the map server is responding to you today.

> In that Florida and Texas represent non-rectilinear (cool word by the
> way) geographic challeneges, I am sure that we can adapt to the
> thinking of the rest...

Well, Texas is pretty big, and there are large chunks of it that are
square, but yes.  Either way, I'd bet that most counties aren't long and
skinny, and that most people will download a county or two at a time,
thus making the big square a reasonable idea.

> P.S. now that we are on the subject when are you going to add aerial
> views and weather to the realtime map overlays. I couldn't
> resist.........

If you find a satellite map service that uses the google maps protocol
and doesn't restrict the usage of their tiles (as does google maps) then
I'm game :)

Thanks!

-- 
Dan Smith
dsmith#danplanet.com, s/#/@/
www.danplanet.com
KK7DS