Ok, so this seems like a possible approach, but applied in reverse (update: in other words, instead of foreach point {foreach poly}}, I am going to do foreach poly {get all points {foreach point {more fine-grained}}..
  1. Generate a SQL table of x,y of all the points
  2. foreach rect bound of poly, find all the points that lie within -- this could be done via SQL -- SELECT points WHERE (point.x > poly.xmin) AND (point.x < poly.xmax) AND (point.y > poly.ymin) AND (point.y < poly.ymax)
  3. do more fine-grained point-in-poly analysis on the points SELECTed in #2 above, either by the said "Wolf Book" algorithm, or just use Math::Geometry::Planar
Sounds like a plan.
--

when small people start casting long shadows, it is time to go to bed

In reply to Re^2: Speeding up point-in-polygon by punkish
in thread Speeding up point-in-polygon by punkish

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