[QGIS-trac] [Quantum GIS] #2703: Incorrect rendering for vector line segments that span -180 line of longitude version 1.4.0

[Quantum GIS]

#2703: Incorrect rendering for vector line segments that span -180 line of
longitude version 1.4.0
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   Reporter:  abigbee                                    |              Owner:  nobody                
       Type:  bug                                        |             Status:  new                   
   Priority:  critical: causes crash or data corruption  |          Milestone:  Version 1.5.0         
  Component:  Vectors                                    |            Version:  1.4.0                 
   Keywords:  vector rendering                           |   Platform_version:  Windows revision 12728
   Platform:  Windows                                    |           Must_fix:  Yes                   
Status_info:  0                                          |  
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 Polygons in vector layers that have line segments with endpoints that span
 the -180 line of longitude are incorrectly rendered.  For example, a line
 with endpoints of 1 degree and  -179 degree will not result in a 2 degree
 line, but rather be rendered as a line of of 180 degrees in length and
 spans. I.e. instead of a short line segment in the Pacific, the line runs
 across North America and the Atlantic.

 I have attached a small test case for a many-side polygon esri shape file
 that I programmatically generated to illustrate this bug.  Upon rendering
 in the GUI, the left side of the western polygon should incorrectly be
 extruded all the way across North America and the Atlantic Ocean.  The
 correct rendering would display a circle-like polygon centered on the
 Alaskan Aleutian Islands.

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Ticket URL: <https://trac.osgeo.org/qgis/ticket/2703>
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