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Geometry : |
Subject: Re: [geometry] Spatial Index for arc
From: Adam Wulkiewicz (adam.wulkiewicz_at_[hidden])
Date: 2013-08-26 17:10:56
Hi,
jeffpoly wrote:
>
> As I understand, the boost geometry does not support arc yet, for
> example,which is defined by three points. I wonder if such arc could be
> used for spatial index queries, the same as linestring or polygon?
>
The rtree internally uses boolean algorithms defined in boost::geometry,
such as intersects() or within(). If the algorithm is implemented for a
Box(or Point) and some Geometry then this Geometry may be used in a query.
I don't know if some kind of Arc concept is planned. Maybe a Bezier
curve which might be used to describe an arc. Unfortunately for now the
arc may be only approximated, e.g. by a LineString.
Alternatively you could try to use nsphere from extensions and after
performing a query for intersection with a circle, filter Values which
are intersecting the interesting part.
Still, probably the most simple solution is quering for Values
intersecting arc's bounding box and then check them manually.
Regards,
Adam
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