Extension [ <persistent> extension #83 geospatial version 0.3.3 ] {

  - Constants [4] {
    Constant [ float GEO_DEG_TO_RAD ] { 0.017453292519943 }
    Constant [ float GEO_EARTH_RADIUS ] { 6378137 }
    Constant [ int GEO_AIRY_1830 ] { 2 }
    Constant [ int GEO_WGS84 ] { 1 }
  }

  - Functions {
    Function [ <internal:geospatial> function dms_to_decimal ] {

      - Parameters [4] {
        Parameter #0 [ <required> float $degrees ]
        Parameter #1 [ <required> float $minutes ]
        Parameter #2 [ <required> float $seconds ]
        Parameter #3 [ <optional> string $direction = "" ]
      }
      - Return [ float ]
    }
    Function [ <internal:geospatial> function decimal_to_dms ] {

      - Parameters [2] {
        Parameter #0 [ <required> float $decimal ]
        Parameter #1 [ <required> string $coordinate ]
      }
      - Return [ array ]
    }
    Function [ <internal:geospatial> function helmert ] {

      - Parameters [5] {
        Parameter #0 [ <required> float $x ]
        Parameter #1 [ <required> float $y ]
        Parameter #2 [ <required> float $z ]
        Parameter #3 [ <optional> int $from_reference_ellipsoid = 0 ]
        Parameter #4 [ <optional> int $to_reference_ellipsoid = 0 ]
      }
      - Return [ array ]
    }
    Function [ <internal:geospatial> function polar_to_cartesian ] {

      - Parameters [3] {
        Parameter #0 [ <required> float $latitude ]
        Parameter #1 [ <required> float $longitude ]
        Parameter #2 [ <optional> int $reference_ellipsoid = 0 ]
      }
      - Return [ array ]
    }
    Function [ <internal:geospatial> function cartesian_to_polar ] {

      - Parameters [4] {
        Parameter #0 [ <required> float $x ]
        Parameter #1 [ <required> float $y ]
        Parameter #2 [ <required> float $z ]
        Parameter #3 [ <optional> int $reference_ellipsoid = 0 ]
      }
      - Return [ array ]
    }
    Function [ <internal:geospatial> function transform_datum ] {

      - Parameters [3] {
        Parameter #0 [ <required> array $coordinates ]
        Parameter #1 [ <required> int $from_reference_ellipsoid ]
        Parameter #2 [ <required> int $to_reference_ellipsoid ]
      }
      - Return [ array ]
    }
    Function [ <internal:geospatial> function haversine ] {

      - Parameters [3] {
        Parameter #0 [ <required> array $from ]
        Parameter #1 [ <required> array $to ]
        Parameter #2 [ <optional> float $radius = GEO_EARTH_RADIUS ]
      }
      - Return [ float ]
    }
    Function [ <internal:geospatial> function vincenty ] {

      - Parameters [3] {
        Parameter #0 [ <required> array $from ]
        Parameter #1 [ <required> array $to ]
        Parameter #2 [ <optional> float $reference_ellipsoid = GEO_WGS84 ]
      }
      - Return [ float ]
    }
    Function [ <internal:geospatial> function fraction_along_gc_line ] {

      - Parameters [3] {
        Parameter #0 [ <required> array $from ]
        Parameter #1 [ <required> array $to ]
        Parameter #2 [ <required> float $fraction ]
      }
      - Return [ array ]
    }
    Function [ <internal:geospatial> function interpolate_linestring ] {

      - Parameters [2] {
        Parameter #0 [ <required> array $line ]
        Parameter #1 [ <required> float $epsilon ]
      }
      - Return [ array ]
    }
    Function [ <internal:geospatial> function initial_bearing ] {

      - Parameters [2] {
        Parameter #0 [ <required> array $from ]
        Parameter #1 [ <required> array $to ]
      }
      - Return [ float ]
    }
    Function [ <internal:geospatial> function rdp_simplify ] {

      - Parameters [2] {
        Parameter #0 [ <required> array $points ]
        Parameter #1 [ <required> float $epsilon ]
      }
      - Return [ array ]
    }
    Function [ <internal:geospatial> function geohash_encode ] {

      - Parameters [2] {
        Parameter #0 [ <required> array $point ]
        Parameter #1 [ <optional> int $precision = 12 ]
      }
      - Return [ string ]
    }
    Function [ <internal:geospatial> function geohash_decode ] {

      - Parameters [1] {
        Parameter #0 [ <required> string $geohash ]
      }
      - Return [ array ]
    }
  }
}