lib/geo_swap.rb in geo_swap-0.0.2 vs lib/geo_swap.rb in geo_swap-0.1.0

@@ -1,21 +1,23 @@
+require 'pry'
 require "geo_swap/version"
 require 'geo_swap/zone'
 require 'geo_swap/utilities'
+require 'geo_swap/utm_point'
 
 module GeoSwap
   extend Utilities
 
   def lat_long_to_utm(lat, long)
     validate_range(lat, long)
     lat_radians = degrees_to_radians(lat)
     long_radians = degrees_to_radians(long)
 
-    zone = Zone.new(long)
+    zone = Zone.new(lat, long)
     origin_radians = degrees_to_radians(zone.origin)
 
-    equator_factor = (EQUATORIAL_RADIUS / Math.sqrt(1 - (ECC_SQUARED * (Math.sin(lat_radians) ** 2)))
+    equator_factor = (EQUATORIAL_RADIUS / Math.sqrt(1 - (ECC_SQUARED * (Math.sin(lat_radians) ** 2))))
     squared_lat_tangent = Math.tan(lat_radians) ** 2
     ecc_prime_factor = ECC_PRIME_SQUARED * (Math.cos(lat_radians) ** 2)
     origin_factor = Math.cos(lat_radians) * (long_radians - origin_radians)
 
 
@@ -34,10 +36,29 @@
       ecc_2 * latRad_2 +
       ecc_3 * latRad_3 -
       ecc_4 * latRad_4
     )
 
+    utm_easting = (MERIDIAN_SCALE * equator_factor * 
+      (origin_factor + (1 - squared_lat_tangent + ecc_prime_factor) *
+      (origin_factor ** 3) / 6 +
+      (5 - 18 * squared_lat_tangent + (squared_lat_tangent ** 2) + 72 * ecc_prime_factor - 58 * ECC_PRIME_SQUARED) *
+      (origin_factor ** 5) / 120) + EASTING_OFFSET)
+
+    utm_northing = (
+      MERIDIAN_SCALE * ( northing_factor + equator_factor * Math.tan(lat_radians) * (origin_factor ** 2) / 2 + (5 - squared_lat_tangent + 9 * ecc_prime_factor + 4 * (ecc_prime_factor ** 2)) * (origin_factor ** 4) / 2 +
+     (61 - 58 * squared_lat_tangent + (squared_lat_tangent ** 2) + 600 * ecc_prime_factor - 330 * ECC_PRIME_SQUARED) *
+     (origin_factor ** 6) / 720))
+
+    utm_northing += 10000000 if utm_northing < 0
+
+    UtmPoint.new(
+      easting: utm_easting.round,
+      northing: utm_northing.round,
+      zone: zone,
+      hemisphere: (lat < 0 ? 'S' : 'N')
+    )
   end
 
   module_function :lat_long_to_utm
 
 
@@ -51,9 +72,13 @@
   MIN_CONVERSION_LATITUDE = -80.0
 
   EQUATORIAL_RADIUS = 6378137.0
   ECC_SQUARED = 0.006694380023
   ECC_PRIME_SQUARED = ECC_SQUARED / (1 - ECC_SQUARED)
+  MERIDIAN_SCALE = 0.9996
+
+  EASTING_OFFSET = 500000.0
+  NORTHING_OFFSET = 10000000.0
 
   def self.validate_range(lat, long)
     unless lat.between?(MIN_LATITUDE, MAX_LATITUDE) && long.between?(MIN_LONGITUDE, MAX_LONGITUDE)
       raise InputError, 'Input coordinates are invalid'
     end