[postgis-tickets] [PostGIS] #3034: ST_AsTWKBagg does not check the input precision

[PostGIS]

#3034: ST_AsTWKBagg does not check the input precision
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 Reporter:  javisantana  |       Owner:  nicklas
     Type:  defect       |      Status:  new    
 Priority:  medium       |   Milestone:         
Component:  postgis      |     Version:  2.1.x  
 Keywords:               |  
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Comment(by nicklas):

 Thanks javisantana!

 I didn't read properly so I added the check a little later in the file. I
 missed the patch. Your placing of the check is more logical, but I leave
 it where it is. I will commit some major rework of the twkb-code anyway
 soon. Then I think as Sandro proposed some time ago that the aggregation
 code should go in a separate file.

 THe reason of the limit of 7 decimals is because it is stored in 4 bts,
 and as discussed
 here:
 https://github.com/TWKB/Specification/issues/5
 and here
 https://github.com/TWKB/Specification/issues/9
 there should probably be possible to use negative values too, for meter
 based projections on low zoom-levels.
 So, since there is still no conclusion about that I have left space for
 allowing negative numbers in one way or another (will need 1 bit no matter
 how it is done I guess).

 Is there a need for more than 7 decimals?
 Well, it can be of course, maybe it should be. I don't know.

 There is still the fourth bit available, but I would like to use that for
 zoom-levels (Is there a bitmap included for zoom-levels). But I have to
 prove that it is usable first :-)

 Anyway this is not the place for this discussion. Github is better as an
 issue for the twkb spec.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/3034#comment:2>
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