[postgis-tickets] [PostGIS] #5382: ST_AsMVTGeom output is snapped to grid incorrectly

[PostGIS]

#5382: ST_AsMVTGeom output is snapped to grid incorrectly
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  Reporter:  mknycha  |      Owner:  pramsey
      Type:  defect   |     Status:  new
  Priority:  medium   |  Milestone:  PostGIS 3.1.10
 Component:  postgis  |    Version:  3.3.x
Resolution:           |   Keywords:
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Comment (by mknycha):

 Here is what is being passed to ST_SnapToGrid in my replicated code:

 Unclipped: POLYGON ((0 20, 8 20, 12 8, -6 10, 0 20))

 Clipped:   POLYGON ((0 9.333, 0 20, 8 20, 12 8, 0 9.333))

 Maybe the issue is not with snapping to the grid, but happens somewhere
 earlier?

 And regarding
 >As far as a problem with MVT, since the snapping is by default happening
 on a 4096x4096 grid I find it hard to get worked up about which particular
 grid cell is getting snapped to.
 I may not fully understand the function, but isn't that the case for the
 default extent? Because I am passing 20 there.
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Ticket URL: <https://trac.osgeo.org/postgis/ticket/5382#comment:3>
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