I'd claim any advantage of a circle could be countered by a set of disjoint covering boxes, and the computational cost would be similar.

Quadtree decomposition is only one way to do it.

And decomposing in smaller circles wouldn't lead to a disjoint set.

(Though the "best" approach is probably partitioning a polygon into triangles anyway )

The inherent catch is that we prefer a cartesian system, hence we'll always prefer a compatible coverage if the costs are similar.

Remember that the OP wanted to preselect (spatial index) plausible candidates, how would you do this with circles?

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

In reply to Re^6: searching polygons not merged by LanX
in thread searching polygons not merged by dideod.yang

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