Concave-convex lens from 2 point clouds

lens.md

shape@ main_shape()
{
   // create 2 convex hull bodies
   solid@ upper =  polyhedron("posterior-lenticle-surface.xyz");
   solid@ lower =  polyhedron("anterior-lenticle-surface.xyz");
  
   // subtract upper from lower to create convex-concave lens body
   return lower-upper;
}

void main()
{
   shape@ obj = main_shape();
   obj.write_xcsg(GetInputFullPath(),secant_tolerance:-1);
}

lens.stl