Copying shapefiles in spatially sorted (.qix) traversal code

[Frank Warmerdam]

On 4/29/05, richard.roger at agric.nsw.gov.au
<richard.roger at agric.nsw.gov.au> wrote:
> I didn't get a positive response, so I did it myself.  My program's based on
> programs in the mapserver distribution (particularly, maptree.c which is
> Frank's). If my memory serves me correctly, it's pretty basic - reads and
> writes each shape one at a time, then reads and writes the DBF file records
> one at a time.  Nevertheless, on our Sun system (a 480R with 16 GB), it
> sorted the entire cadastre for my state (1.3 GB, 4 million polygons) in
> about 8 minutes. I've marginally altered Frank's spatial indexing so that it
> visits nodes following a Hilbert-Peano scan, so that sequential nodes are
> spatially adjacent. 

Richard, 

Cool! When you submit the code, please be fairly specific about
this "Hilbert-Peano Scan" as I would potentially like to apply it
in the seperate version of the spatial index code in in shapelib
and OGR. 
  
> I shall re-visit my code and polish it up.  It would fit in with "shptree"
> and  "maptree" from which it's derived.  What's the best way of contributing
> this to the codebase? 

Please submit the updates via bugzilla. 

Best regards,
-- 
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