[geos-devel] Indexing question from a newbie

[Paul Ramsey]

I am not a programmer, so I can't give you code snippets. I can tell you 
that if your tiles are regularly sized and regularly spaced (as the term 
"tile" hints) probably the quadtree will be marginally more 
efficient/faster.

WRT your actual problem, depending on your implementation requirements 
using PostGIS/PostgreSQL rather than coding from scratch will certainly 
be easier. The suitability of that kind of solution obviously depends on 
where you are going to deploy the final product, of course.

P.

Sudipta Sarkar wrote:
> Hi All,
> I am trying to use GEOS to create envelope geometries for a bunch of 
> different tiles and create a spatial index based on these geometries. 
> The purpose is to select features lying within a particular tile based 
> on an initial query on the spatial index of these different tiles. I am 
> a complete newbie to GEOS so was hoping if anyone can suggest as to 
> which index amidst Quadtree and SRTree will work best for my purpose. It 
> will also be helpful if anyone can point me to any example script in 
> C/C++ that uses GEOS to build indexes and query them.
> 
> Any help is appreciated.
> Thanks