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https://issues.apache.org/jira/browse/LUCENE-6196?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14291812#comment-14291812
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Nicholas Knize commented on LUCENE-6196:
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I don't know that its necessary to determine the expense of computing bounding
boxes for irregular shapes (if for only satisfying curiosity). Its a known
problem with doing all computation in equirectangular lat/lon (or any single
projection, for that matter) a choice is being made to sacrifice accuracy at
some level. Its why there exists so many different projections for various
parts of the earths surface. Spherical (or ellipsoidal) mathematics using an
approximation of the earth is just plain inaccurate since there is no perfect
model of the earth's shape. To achieve the best accuracy for large irregular
polygon's one will either reproject the data into a more accurate projection,
slice the polygon into smaller (more accurate) polygons, introduce something
like a bloom filter for catching inaccurate boundary conditions, or.... insert
other options here.... All of which are going to be just as, or more,
expensive.
I'm all for spending time working up the fastest, most accurate logic (its a
responsibility for any mature mapping or GIS utility). But it needs to be well
documented and at the choice of the end user. For 95% of private sector users,
great-circle is OK. For public-sector applications on the other hand.
> 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: ShapeImpl.java, 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.
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