Re: Define spatial reference system for local datum

>
> A lot of these tools that connect to postigs db requires a srid.  I was
> trying out Udig.  I don't need to use these tools.  I can just work with
> shapefile and import it to postgis.
>
> But what I'm worry about is if I use a defined srid like EPSG:4326 and my
> personal map coordinates will mess up because of the projection.  The world
> I'm mapping is flat and endless, it doesn't wrap around like earth map.
>
>
>
>
> Sean Fulton wrote:
>>
>> Can you just set the SRID to -1.  What 'map design tool' are you
>> using?
>>
>> Sean
>>
>> On Jun 30, 3:00 pm, tommy408 <tommytomo...@...> wrote:
>>> I'm not mapping anything on earth.  The world I'm doing is flat.  The
>>> polygons I'm drawing over is raster image I made.  So I'm trying not to
>>> use
>>> any ellipsoid projection.
>>>
>>>
>>>
>>> Suhr, Ralf wrote:
>>>
>>>> Do not use a local system. For everything larger than 200meters you
>>> need a
>>>> srs definition, because you can't messure it exactly.
>>>
>>>> Take a projection from your living area und shift your geometrys to the
>>>> right place.
>>>
>>>> -----Ursprüngliche Nachricht-----
>>>> Von: postgis-users-boun...@...
>>>> [mailto:postgis-users-boun...@...] Im Auftrag von
>>>> tommy408
>>>> Gesendet: Dienstag, 30. Juni 2009 12:26
>>>> An: postgis-us...@...
>>>> Betreff: [postgis-users] Define spatial reference system for local
>>> datum
>>>
>>>> I don't need special projection.  My map is a flat plane so I'm trying
>>> to
>>>> use local datum as my srs because a bunch of gis map design tool ask
>>> for
>>>> it.
>>>
>>>> So I'm trying to add a new srs into postgis spatial_ref_sys table with
>>> the
>>>> following srstext
>>>
>>>> LOCAL_CS["Non-Earth (Meter)",LOCAL_DATUM["Local Datum",0],UNIT["Meter",
>>>> 1],AXIS["X",EAST],AXIS["Y",NORTH]]
>>>
>>>> What do I put for proj4text?
>>>> --
>>>> View this message in context:
>>>> http://www.nabble.com/Define-spatial-reference-system-for-local-datum...
>>>> Sent from the PostGIS - User mailing list archive at Nabble.com.
>>>
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