? TransverseMercator

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BMN, IrishGrid, NZTM2000, OSGB, SloveneGrid, UTM

public abstract class TransverseMercator extends Projection

TransverseMercator is an abstract base class for coordinate systems derived from the Transverse Mercator Projection. Methods are provided for standard conversions between Lat/Lon and Easting/Northing

Concrete sub-classes derived from TransverseMercator need to provide values for the projection constants f0(), phi0(), n0(), e0() and lamda0() (see below).

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    • northernHemisphere

      protected boolean northernHemisphere
    • zone

      protected int zone
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    • TransverseMercator

      protected TransverseMercator()
      Default constructor for TransverseMercator
    • TransverseMercator

      public TransverseMercator(Position p, Ellipsoid e, Datum d)
      Create a new TransverseMercator instance for a location specified by Position, Ellipsoid and Datum
      ??:
      p - A Position object defining the location
      e - The Ellipsoid used as a reference
      d - The Datum used
    • TransverseMercator

      public TransverseMercator(ENPair point, Ellipsoid sphere, Datum datum)
      Create an instance of TransverseMercator based on a specified ENPair
      ??:
      point - An ENPair containing the Easting and Northing distances of the point
      sphere - The Ellipsoid to use
      datum - The Datum to use with this instance
    • TransverseMercator

      protected TransverseMercator(ENPair point, int z, Ellipsoid sphere, Datum datum, boolean hemisphere)
      Create an instance of TransverseMercator based on a specified ENPair
      ??:
      sphere - The Ellipsoid to use
      z - UTM Zone number
      datum - The Datum to use with this instance
      point - An ENPair containing the Easting and Northing distances of the point
      hemisphere - true if the point is in the Northern hemisphere
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    • toEN

      public ENPair toEN()
      Provide an ENPair containing Easting and Northing distances for this point
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      toEN ??? Projection
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      an ENPair
    • gridConvergence

      public double gridConvergence()
      Calculate the Grid Convergence for the current location. Grid Convergence is defined as the angle between Grid North and True North. The value is zero on the Central Meridian.
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      gridConvergence ??? Projection
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      The value of Grid Convergence (radians)
    • pointScaleFactor

      public double pointScaleFactor()
      Calculate the Point Scale Factor for the current Position. This is f0() on the central meridian.
      ??:
      The Point Scale Factor
    • f0

      public abstract double f0()
      The scale factor on the Central Meridian. Generally, Transverse Mercator projections increasingly exagerate distances further from the central meridian. It is usual to reduce the scale factor at the central meridian to compensate for this effect and optimise the scale over the area of interest.
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      the value of the ScaleFactor at the central meridian.
    • phi0

      public abstract double phi0()
      phi0() defines the latitude of the true origin of the projection. Note, however, that many Transverse Mercator projections employ a false origin. See n0() and e0() below.
      ??:
      The latitude of the true origin (radians)
    • n0

      public abstract double n0()
      n0() defines the "false northing" distance of the projection. False origins are usually used with TM projections to ensure that easting and northing distances are always positive over the area of interest. n0() is used as an offset to the grid so that the "true origin" appears to have a northing value equal to n0().
      ??:
      The false northing distance (double)
    • e0

      public abstract double e0()
      e0() defines the "false easting" distance of the projection. False origins are usually used with TM projections to ensure that easting and northing distances are always positive over the area of interest. e0() is used as an offset to the grid so that the "true origin" appears to have an easting value equal to e0().
      ??:
      The false easting distance (double)
    • lamda0

      public abstract double lamda0()
      lamda0() defines the longitude (in radians) of the true origin also known as the "Central Meridian".
      ??:
      The central meridian (radians)