[postgis-tickets] [PostGIS] #3412: geometry intersects edge on TopoGeo_addLinestring with tolerance 0.001

[PostGIS]

#3412: geometry intersects edge on TopoGeo_addLinestring with tolerance 0.001
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  Reporter:  strk      |      Owner:  strk
      Type:  defect    |     Status:  new
  Priority:  medium    |  Milestone:  PostGIS 2.2.1
 Component:  topology  |    Version:  2.0.x
Resolution:            |   Keywords:
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Comment (by strk):

 Alright now I see the snap problem. Initially, only the last (uppermost)
 target vertex is below tolerance. The snapper snaps the single input
 segment to this point.

 The snapping moves the subject line closer to the other vertex, so it is
 _now_ below tolerance, but the snapper does not recurse to further snap
 the now-moved line.

 In the picture you see a portion of the target line (existing edge, in
 green), the line being added before snapping (rightmost, violet) and the
 line being added after snapping (the red one). The distance between the
 green vertex and the violet line is above tolerance while the distance
 between the green vertex and the red line is below tolerance.


 [[Image(snapfail.png)]]

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/3412#comment:5>
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