[postgis-tickets] [PostGIS] #2422: geography regression difference ST_DWithin

[PostGIS]

#2422: geography regression difference ST_DWithin
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 Reporter:  robe     |       Owner:  pramsey      
     Type:  defect   |      Status:  new          
 Priority:  high     |   Milestone:  PostGIS 2.1.0
Component:  postgis  |     Version:  2.1.x        
 Keywords:           |  
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Comment(by pramsey):

 The answer regarding why have a dwithin code line is because the distance
 code line doesn't actually use the tolerance when evaluating two trees
 against one another, while the dwithin code line does. The idea is the
 dwithin line can short circuit out of the evaluation when it hits
 something within tolerance, while the distance calculation has to check
 all possibilities to get the right distance. However, the distance code
 line does take in a tolerance number, it just mostly ignores it.

 What this case is showing is a failure in the tolerance-based code,
 perhaps, although you also have a case that shows the tree and segment
 based distance calculations coming up different.

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/2422#comment:17>
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