[Xastir] Open Street Map support (read this)

[Tom Russo]

On Wed, Jun 09, 2010 at 01:48:00PM -0700, we recorded a bogon-computron collision of the <curt.we7u at gmail.com> flavor, containing:
> On Wed, 9 Jun 2010, Tom Russo wrote:
> 
> > I also note that the code appears to be changing requested zoom levels to match
> > OSM zoom levels.  This may or may not be desirable (I was puzzled when I tried
> > to set a custom zoom level to a particular value, and the code repeatedly
> > set it to something else).
> 
> Tom:  I can send you the original patch if you'd like to see what
> was done.

I can see what's been done using cvs diff.

> Perhaps you can help Jerry with the tweaks (if he needs/wants help).
> Perhaps I can too.

I don't really have time to mess with it.  But I see that the function
adj_to_OSM_levels is called in just one place in main.c, and depends on
a global variable (OSMserver_flag) being set elsewhere.  Clearly, that 
variable is not set correctly when a map bookmark is read, nor at start-up,
only when zooming around or while choosing a custom zoom level.  If the 
current scheme of only allowing zoom levels that match OSM zoom levels
(which is certainly workable, if not ideal) is maintained, that 
adj_to_OSM_levels needs to get called every time a zoom level setting is
attempted while OSM maps are selected, and it isn't currently being done
in all such cases.

-- 
Tom Russo    KM5VY   SAR502   DM64ux          http://www.swcp.com/~russo/
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