Module: Base::Project::App::Models::Concerns::Localizable::ClassMethods

Defined in:
lib/base/project/app/models/concerns/localizable.rb

Instance Method Summary collapse

Instance Method Details

#destination_point(lat, lng, initial_bearing, distance) ⇒ Object

Return destination point given distance and bearing from start point



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# File 'lib/base/project/app/models/concerns/localizable.rb', line 25

def destination_point(lat, lng, initial_bearing, distance)
  d2r = ->(x) { x * Math::PI / 180 }
  r2d = ->(x) { x * 180 / Math::PI }

  lat ||= 0
  lng ||= 0

  angular_distance = distance / 6371.0

  lat1 = d2r.call(lat)
  lng1 = d2r.call(lng)
  bearing = d2r.call(initial_bearing)

  lat2 = Math.asin(Math.sin(lat1) *
                   Math.cos(angular_distance) +
                   Math.cos(lat1)             *
                   Math.sin(angular_distance) *
                   Math.cos(bearing))

  lng2 = lng1 + Math.atan2(Math.sin(bearing) * Math.sin(angular_distance) * Math.cos(lat1),
                           Math.cos(angular_distance) - Math.sin(lat1) * Math.sin(lat2))

  { lat: r2d.call(lat2).round(7), lng: r2d.call(lng2).round(7) }
end