[Xastir] OSM Oddity

[Curt, WE7U]

On Sat, 12 Jun 2010, Jerry Dunmire wrote:

> Thanks for the report. I kind of expected something like that, but my
> first attempt to fix it with the binned levels didn't work so I
> decided to postpone further work on fixing the boxed (area) zoom
> function until the linear scaling is working. I really expect the zoom
> to work just fine (with linear scaling) since that part of the appears
> to have received special attention.

Yea, it's always worked perfectly since written, zooming in to the
area enclosed by the box, plus sometimes a little extra area to
maintain the aspect ratio.  In other words the area enclosed by the
zoom box will be visible when done, and you'll be zoomed in as close
to that zoom box as Xastir can do.  With the OSM code pinning to the
zoom levels that OSM can provide it messed up the whole scheme
there.


> The OSM workaround for now is to draw boxes that have the same (or
> nearly the same) aspect ratio as the display window and enclose more
> than the needed area.

Don't worry about going for the closest aspect ratio.  What you need
to make sure of is that you have at least the area enclosed by the
Xastir view in the map.  It doesn't matter how much MORE is in the
map image, Xastir will ignore it.  Make sure you pick the largest of
the X/Y in Xastir's viewport and then make sure the OSM image you're
fetching has at least that much in that dimension.

-- 
Curt, WE7U.                         <http://www.eskimo.com/~archer>
    APRS:  Where it's at!                    <http://www.xastir.org>
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