[Xastir] no zoom levels under 15 with osm maps

[Curt, WE7U]

On Mon, 28 Jun 2010, Jerry Dunmire wrote:

> Yes, I have started to look at using the tile servers. I expect much better
> performance when using cached tiles.

We could also play the same trick as a lot of the web-page mapping
systems that use tiles:  Pre-download tiles outside the map edges so
that a pan in any direction will have all the tiles it needs for
display.  That's one of the ways they achieve the "apparent" speed:
They download tiles in the background after you receive the initial
map.

One could extend that technique to snag tiles at the next zoom level
up/down as well.

-- 
Curt, WE7U.                         <http://www.eskimo.com/~archer>
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