code: private static GeometricParity geometric(Map<IAtom, Integer> elevationMap, List<IBond> bonds, int i,
              int[] adjacent, IAtomContainer container) {
          int nStereoBonds = nStereoBonds(bonds);
          if (nStereoBonds > 0)
              return geometric2D(elevationMap, bonds, i, adjacent, container);
          else if (nStereoBonds == 0) return geometric3D(i, adjacent, container);
          return null;
      }
docs: Create the geometric part of an encoder
  
  @param elevationMap temporary map to store the bond elevations (2D)
  @param bonds        list of bonds connected to the atom at i
  @param i            the central atom (index)
  @param adjacent     adjacent atoms (indices)
  @param container    container
  @return geometric parity encoder (or null)