dapi

class AddTypusAttributesToUsers < ActiveRecord::Migration
  def self.up
    add_column :users, :role, :string
    add_column :users, :status, :boolean, :null=>false, :default=>true
    User.find(1).update_attribute(:role,'admin')
  end

  def self.down
    remove_column :users, :role
    remove_column :users, :status

rgeo-center.rb

require 'rgeo'

g = RGeo::Geographic.simple_mercator_factory

n, e, s, w = 50, 40, 10, 20

box = RGeo::Geographic::ProjectedWindow.bounding_points([g.point(w,s), g.point(e,n)])