[postgis-devel] SnapToGrid support of circular string

[Mark Cave-Ayland]

On 13/04/11 21:24, Sandro Santilli wrote:

> Does it make sense to threat a CircularString the
> same as a LineString when it comes to snapping it
> to a grid ?
>
> Adding such support would help fixing ticket #183,
> which is a regress test failing due to precision on 32bits:
>
>   COMPOUNDCURVE(
>     CIRCULARSTRING(0 0,0.500000000000184 1.20710678118655,1 0),
>     (1 0,0 1)
>   )
>
> Sorry for the lame question but I haven't found semantic
> of CIRCULARSTRING on the postgis manual

I think you need to consult the SQL-MM specification for this - I'm not 
sure whether snapping should just affect control points or something else?

Can you post a reference when you find out what the behaviour should be 
so it is documented for the archives?


ATB,

Mark.

-- 
Mark Cave-Ayland - Senior Technical Architect
PostgreSQL - PostGIS
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