I've been searching for a function to make the Convex Hull of a Spatial Object with N points, to make an spatial approximation with n-corners, as shown in the article "Comparison of Approximations of Complex Objects Used for Approximation-based Query Processing in Spatial Database Systems", by Thomas Brinkhoff, Hans-Peter Kriegel and Ralf Schneider. I haven't found any function to make this, I searched for any GEOS function but didn't find. Does anybody know what can I use for it?
It is often used to determine an affected area based on a set of point observations.
Also worth nothing,
It is usually used with MULTI and Geometry Collections. Although it is not an aggregate - you can use it in conjunction with ST_Collect to get the convex hull of a set of points. ST_ConvexHull(ST_Collect(somepointfield)).
So run inputs to
ST_Collect first if you're using it as an aggregate.