[postgis-tickets] [PostGIS] #2613: st_curvetoline not accurate

[PostGIS]

#2613: st_curvetoline not accurate
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 Reporter:  hassony  |       Owner:  pramsey      
     Type:  defect   |      Status:  new          
 Priority:  high     |   Milestone:  PostGIS 2.0.5
Component:  postgis  |     Version:  2.0.x        
 Keywords:           |  
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Comment(by pramsey):

 I'm not seeing the same effect here (osx 10.9, clang, pgsql 9.2).
 {{{
 with curve as (
   select st_curvetoline(
   'CURVEPOLYGON(CIRCULARSTRING(-192.63 96.09,-236.72 -84.3,-262.33
 -256.89,-267.71 -409.94,-252.5 -533,-217.73 -617.69,-165.78
 -658.24,-100.19 -651.89, -25.42 -599.06,53.44 -503.37,130.99
 -371.32,201.97 -211.92,261.53 -36.04,305.62 144.35,331.23 316.94,336.61
 469.99,321.4 593.05,286.64 677.74,234.69 718.29,169.09 711.94,94.32
 659.11,15.47 563.42,-62.09 431.37,-133.07 271.98,-192.63 96.09))'
   ) as curve ),
 startend as (
   select
     st_y(st_startpoint(st_exteriorring(curve))) as s,
     st_y(st_endpoint(st_exteriorring(curve))) as e
   from curve )
 select s = e from startend;
 }}}
 And in reviewing the code, line 234 in lwsegmentize.c actually adds the
 first coordinate of the original line without alteration to the
 segmentized version. So I cannot even see programmatically how coordinate
 drift could be introduced. Any further examples? Smaller ones?

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/2613#comment:1>
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