Hi,
On Friday 17 February 2006 01:51, David Luff wrote:
> I'm considering the problem of looking up global data at the moment (eg.
> how many navaids are within x miles of point p). So far I've only
> implemented this in a very crude manner, by indexing a map of navaid
> pointers using FG bucket number, and then traversing all the navaids in the
> user's bucket and concentric rings of buckets out from the user to the
> required distance. This works, but is somewhat ugly, and requires more
> navaids / buckets to be checked than may be necessary due to the non-square
> bucket size and potential for non-centered position of the user within a
> bucket.
>
> I'm sure there must be a better way, and I'm sure Norman has posted links
> on this subject to the list before, but I can't find them, and can't seem
> to find a good method. Anyone got any ideas?
Hierarchical bounding boxes or octrees or something like that.
Having that would be beneficial for the groundcache too.
Ok, thinking loud:
May be it is possible to build a quadtree for the earths surface. No clue if
you *really* gain something vs the 3d approach appart from having fun
thinking about that problem :)
Other question:
With the available tools the bucket indexed map is a good choice for that
thing.
Does it really hurt to use your current approach?
How often are these navid lookups required per frame and how long does this
take?
Greetings
Mathias
--
Mathias Fröhlich, email: [EMAIL PROTECTED]
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