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https://issues.apache.org/jira/browse/LUCENE-7270?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15268978#comment-15268978
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Karl Wright commented on LUCENE-7270:
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So here's my next idea, which is to use the basic tree code that's currently in
place, but optimize up front for tree depth. The way this would work would be
to order edges by edge length (longest first), so that these would appear at
the highest levels of the tree, while the shortest would appear at the leaves.
This would minimize the need to put the same edge into two adjoining subtrees,
which will make the tree smaller. Sorting by edge length would also tend to
randomize the edges enough that we'd not have any strict sequence of edges all
lining up as a depth-first row.
Should be easy enough to try; will get on it after lunch.
> Use better balanced trees for Geo3d complex polygons
> ----------------------------------------------------
>
> Key: LUCENE-7270
> URL: https://issues.apache.org/jira/browse/LUCENE-7270
> Project: Lucene - Core
> Issue Type: Improvement
> Components: modules/spatial3d
> Reporter: Karl Wright
> Assignee: Karl Wright
>
> The current tree data structure in GeoComplexPolygon has a lot of weaknesses.
> A better algorithm maybe can be taken from Polygon2D, which basically does
> the following:
> Each node has:
> - low value (which is for that edge alone)
> - max value (which is for that edge and all children)
> Balanced tree building:
> - sort by low value (which is for the individual edge), and use max value as
> tie breaker (which is max for edge and all children)
> - build tree after sorting, picking midpoint and recursively building lesser
> and greater children that way
> Balanced tree traversal (looking for range minValue -> maxValue):
> - Descend the entire tree until the node fails this test:
> if (minValue <= max) { ... }
> So if the minimum value being sought is greater than the max for this edge
> and all children, we stop and don't look at children.
> (Q: does this represent a good split and a targeted range? Maybe... We
> can certainly try it.)
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