code: @Deprecated
      public GeographyPointValue add(GeographyPointValue offset, double alpha) {
          // The addition of 0.0 converts
          // -0.0 to 0.0.
          return GeographyPointValue.normalizeLngLat(getLongitude() + alpha * offset.getLongitude() + 0.0,
                                                     getLatitude()  + alpha * offset.getLatitude() + 0.0);
      }
docs: Return a point which is offset by the given offset point multiplied by alpha.
  That is, the return value is <code> this + alpha*offset</code>, except that
  Java does not allow one to write it in this way.
  
  In particular, <code>this - other</code> is equal to
  <code>add(other, -1)</code>, but fewer temporary objects are
  created.
  
  Normalize the coordinates.
  @param offset  A point to add to this.
  @param alpha   Coordinates of offset will be scaled by this much.
  @return A new point offset by the scaled offset.