[
https://issues.apache.org/jira/browse/LUCENE-6196?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14491763#comment-14491763
]
Karl Wright commented on LUCENE-6196:
-------------------------------------
Hi Martin,
The geo3d package is based wholly on the unit sphere centered on an x,y,z
coordinate origin. There is no place where the radius of the earth etc factor
into the math. In order to cast the problem in terms of any particular
standard, therefore, you need to multiply distances computed by the radius of
the earth.
Oblateness is also not considered for the purposes of this package. Its best
use is in conjunction with maps which also are projected to a sphere. Luckily
this happens to be quite common.
> Include geo3d package, along with Lucene integration to make it useful
> ----------------------------------------------------------------------
>
> Key: LUCENE-6196
> URL: https://issues.apache.org/jira/browse/LUCENE-6196
> Project: Lucene - Core
> Issue Type: New Feature
> Components: modules/spatial
> Reporter: Karl Wright
> Assignee: David Smiley
> Attachments: LUCENE-6196_Geo3d.patch, ShapeImpl.java,
> geo3d-tests.zip, geo3d.zip
>
>
> I would like to explore contributing a geo3d package to Lucene. This can be
> used in conjunction with Lucene search, both for generating geohashes (via
> spatial4j) for complex geographic shapes, as well as limiting results
> resulting from those queries to those results within the exact shape in
> highly performant ways.
> The package uses 3d planar geometry to do its magic, which basically limits
> computation necessary to determine membership (once a shape has been
> initialized, of course) to only multiplications and additions, which makes it
> feasible to construct a performant BoostSource-based filter for geographic
> shapes. The math is somewhat more involved when generating geohashes, but is
> still more than fast enough to do a good job.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
