Function S2Loop.boundaryNear

Returns true if the two loop boundaries are within "max_error" of each other along their entire lengths. The two loops may have different numbers of vertices. More precisely, this method returns true if the two loops have parameterizations a:[0,1] -> S^2, b:[0,1] -> S^2 such that distance(a(t), b(t)) <= max_error for all t. You can think of this as testing whether it is possible to drive two cars all the way around the two loops such that no car ever goes backward and the cars are always within "max_error" of each other.

bool boundaryNear (
  in const(S2Loop) b,
  S1Angle max_error = fromRadians(1e-15)
) const;