paleolimbot commented on issue #3154:
URL: https://github.com/apache/sedona/issues/3154#issuecomment-5083565731

   The two are more or less identical with the current set up....in order to 
generate a Geography convex hull you have to add points along the edges. We 
have that version parameterized with an accuracy in meters in SedonaDB 
(`ST_TessellateGeog()`), so at least you get to choose the error you're 
comfortable with.
   
   The current version of that is still not quite as accurate as densifying 
edges in the original coordinate system (because the tessellation is only 
implemented from planar lon/lat to spherical lon/lat...it's possible to 
consider a different coordinate system but it isn't there yet).
   
   In other words, it's not the spherical edges of the raster convex hull, it's 
the transformation between coordinate systems that render four points 
inadequate to calculate potential intersection. 10 points along each edge is an 
easy way to improve accuracy without changing behaviour for the common 
case...if we want to do the Geography thing we can invent a new predicate 
(`RS_DWithin()`?) that takes into account error tolerance.


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