[aprssig] USA map sources

[Curt, WE7U]

On Mon, 14 Mar 2005, Stephen H. Smith wrote:

> "Troposervers"????  Don't have the faintest idea what you are referring
> to.

Toposerver.


> If so, this is a software add-in to UI-View that allows a commercial
> CD-ROM mapping product (Undertow Software's Precision Mapping ) to used
> instead of fixed maps in UI-View.  You get a continuously scrollable
> view  of ALL of North American that can be zoomed from a
> continental-sized view, through state and county level, all the down to
> street level showing just a few blocks across anywhere in the USA or
> Canada.   UI-View treats all of this as a "single map".

So can Xastir, using different servers.  See below.


> Are you referring to the "Tiger Maps" produced by the U.S. Census Bureau
> or the topo maps produced by the U.S. Geologic Survey?
>
> The government-compiled data on these maps is in the public domain, and
> is available for free off U.S. government web sites.  (This situation in
> the U.S. is in sharp contrast with the situation in most other countries
> where private companies and users pay sizable fees and royalties for the
> use of public data.)
> However the data is not in forms directly usable by most programs. It
> often requires considerable manipulation and conversion to be usable.
> [WinAPRS and Xastir can use this kind of data after downloading huge
> files from the Internet.]

Huh?  Not that huge.  Depends on what area you're after.  If you're
after just a few counties, it's not a big deal.  We've just gotten
the 2004 data processed into Shapefiles for use by Xastir, so you
can now get the most current data available downloaded to your local
hard drive.  On the 6.4GB drive in my mobile computer I have all of
the topo's for my county plus the street data for that county and
surrounding counties.  Plus Linux.  Plus Xastir.

If you're on the internet with Xastir, just tell it to use the
Tigermap server directly and you won't have to download any raw map
files.  You just pan/zoom at will and a map comes in from the
internet that matches your current view.  That works the same for
several internet map sources, not just Tigermap (topo images,
satellite images, weather radar images).

--
Curt, WE7U.   APRS Client Comparisons: http://www.eskimo.com/~archer
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