module GeoCalc::Midpoint

Public Class Methods

midpoint_to(base_point, point) click to toggle source

Returns the midpoint between this point and the supplied point. see(#mathforum.org/library/drmath/view/51822.html for derivation)

@param [GeoPoint] base_point: Starting point (latitude, longitude) @param [GeoPoint] point: Destination point (latitude, longitude) @return [Array] Midpoint between this point and the supplied point

# File lib/geo_calc/calc/midpoint.rb, line 14
def self.midpoint_to base_point, point
  lat1 = base_point.lat.to_rad
  lon1 = base_point.lon.to_rad;
  lat2 = point.lat.to_rad
  dlon = (point.lon - base_point.lon).to_rad

  bx = Math.cos(lat2) * Math.cos(dlon)
  by = Math.cos(lat2) * Math.sin(dlon)

  lat3 = Math.atan2(Math.sin(lat1)+Math.sin(lat2), Math.sqrt( (Math.cos(lat1)+bx)*(Math.cos(lat1)+bx) + by*by) )

  lon3 = lon1 + Math.atan2(by, Math.cos(lat1) + bx)

  [lat3.to_deg, lon3.to_deg]
  # GeoPoint.new
end

Public Instance Methods

midpoint_to(point) click to toggle source
# File lib/geo_calc/calc/midpoint.rb, line 3
def midpoint_to point
  GeoCalc::Midpoint.midpoint_to self, point
end