Package com.luciad.projection

Class TLcdTransverseMercator

java.lang.Object
com.luciad.projection.ALcdProjection
com.luciad.projection.ALcdTransverseCylindrical
com.luciad.projection.TLcdTransverseMercator
All Implemented Interfaces:
ILcdProjection, ILcdTransverseCylindrical, ILcdPropertyChangeSource, Serializable, Cloneable
public class TLcdTransverseMercator extends ALcdTransverseCylindrical
Transverse Mercator projection.

Introduction

The transverse Mercator projection is an adaptation of the Mercator projection. In the transverse Mercator, the cylinder is rotated 90° (transverse) relative to the equator so that the projected surface is aligned to a central meridian rather than to the equator.

Properties

  • The projection is conformal.
  • The central meridian, each meridian 90° from the central meridian and the Equator are shown as straight lines.
  • Other meridians and parallels are shown as complex curves.
  • Scale is true along the central meridian.
  • Scale becomes infinite on the sphere 90° from the central meridian.

Example

Sample code


 ILcdProjection projection =
     new TLcdTransverseMercator(-30.0);

Implementation aspects

The equations of the transverse mercator projection are taken from [Snyder1987] for a small zone around the central meridian and from [BugaSnyder1995] otherwise.

See Also:

  • Constructor Details

    • TLcdTransverseMercator

      public TLcdTransverseMercator()
      Constructs a transverse mercator projection with the origin of the projection at (0.0,0.0).

    • TLcdTransverseMercator

      public TLcdTransverseMercator(double aCentralMeridian)
      Constructs a transverse mercator projection with the origin of the projection at the specified central meridian and a latitude of origin at zero.
      Parameters:
      aCentralMeridian - the centralMeridian of the projection.

    • TLcdTransverseMercator

      public TLcdTransverseMercator(double aCentralMeridian, double aOriginLat)
      Constructs a transverse mercator projection with the origin of the projection at the specified central meridian and latitude of origin.
      Parameters:
      aCentralMeridian - the centralMeridian of the projection.
      aOriginLat - the latitude of origin of the projection

  • Method Details

    • calculateCachedValues

      protected void calculateCachedValues()
      Description copied from class: ALcdTransverseCylindrical
      Constants based on the central meridian of the projection don't have to be recalculated every time a method is called. They only have to be calculated when the projection properties change. Within the methods the precalculated values then can be used in order to gain efficiency.
      Overrides:
      calculateCachedValues in class ALcdTransverseCylindrical

    • lonlatheight2worldOnSphereSFCT

      public void lonlatheight2worldOnSphereSFCT(ILcdPoint aLLHP, double aRadius, ILcd2DEditablePoint aXYPointSFCT) throws TLcdOutOfBoundsException
      For the spherical case the transverse mercator projection is a simple Gauss-Lambert projection.
      Parameters:
      aLLHP - point to be projected.
      aRadius - radius of the sphere (meters).
      aXYPointSFCT - projected point as side effect.
      Throws:
      TLcdOutOfBoundsException - aLLHP is outside the area valid for this projection.

    • lonlatheight2worldOnEllipsoidSFCT

      public void lonlatheight2worldOnEllipsoidSFCT(ILcdPoint aLLHP, ILcdEllipsoid aEllipsoid, ILcd2DEditablePoint aXYPointSFCT) throws TLcdOutOfBoundsException
      The Gauss-Krüger projection is determined by three conditions: conformality, symmetrical around central meridian, and preservation of linear scale along the central meridian. Because of the use of a truncated series the projection is not strictly conformal but with a sufficient number of terms it will be in practice.

      When the longitude difference is equal to 3º0', the accuracy is up to 0.001m.

      Specified by:
      lonlatheight2worldOnEllipsoidSFCT in interface ILcdProjection
      Overrides:
      lonlatheight2worldOnEllipsoidSFCT in class ALcdProjection
      Parameters:
      aLLHP - point to be projected.
      aEllipsoid - ellipsoid on which the point is defined.
      aXYPointSFCT - projected point as side effect.
      Throws:
      TLcdOutOfBoundsException - If the ILcdPoint aLLHP is not within the valid area of the projection (visible area), then this exception is thrown.

    • world2lonlatOnSphereSFCT

      public void world2lonlatOnSphereSFCT(ILcdPoint aXYPoint, double aRadius, ILcd2DEditablePoint aLLPSFCT) throws TLcdOutOfBoundsException
      Description copied from interface: ILcdProjection
      Transforms an ILcdPoint from the cartesian coordinate system of the projection into an ILcd2DEditablePoint onto a sphere.
      Parameters:
      aXYPoint - projected point for which the corresponding geodetic point is sought.
      aRadius - radius of the sphere (meters).
      aLLPSFCT - resulting geodetic coordinate as side effect.
      Throws:
      TLcdOutOfBoundsException - If the ILcdPoint aXYPoint is not within the valid area of the projection (visible area), then this exception is thrown.

    • world2lonlatOnEllipsoidSFCT

      public void world2lonlatOnEllipsoidSFCT(ILcdPoint aXYPoint, ILcdEllipsoid aEllipsoid, ILcd2DEditablePoint aLLPSFCT) throws TLcdOutOfBoundsException
      Description copied from class: ALcdProjection
      Default implementation calls world2lonlatOnSphereSFCT with aEllipsoid.getAuxRadius() as sphere radius.
      Specified by:
      world2lonlatOnEllipsoidSFCT in interface ILcdProjection
      Overrides:
      world2lonlatOnEllipsoidSFCT in class ALcdProjection
      Parameters:
      aXYPoint - projected point for which the corresponding geodetic point is sought.
      aEllipsoid - ellipsoid on which the geodetic coordinate is defined.
      aLLPSFCT - resulting geodetic coordinate as side effect.
      Throws:
      TLcdOutOfBoundsException - If the ILcdPoint aXYPoint is not within the valid area of the projection (visible area), then this exception is thrown.

    • isAllInBounds

      public boolean isAllInBounds()
      Description copied from interface: ILcdProjection
      If all geodetic coordinates (l ,j ) are projected (visible) by an ILcdProjection and all (x,y ) coordinates are bounded this is true. All ILcdProjection objects have bounded (x,y ) coordinates because the projection is cut off if necessary.
      Returns:
      true if all LonLatPoints are within the bounds of the projection, false otherwise.

    • isContinuous

      public boolean isContinuous()
      Description copied from interface: ILcdProjection
      An ILcdProjection is continuous if there are no interruptions in the world coordinates. Most projections are continuous.
      Specified by:
      isContinuous in interface ILcdProjection
      Overrides:
      isContinuous in class ALcdTransverseCylindrical
      Returns:
      true if the projection is continuous, false otherwise.

    • inLonLatBounds

      public boolean inLonLatBounds(ILcdPoint aLLP)
      Description copied from interface: ILcdProjection
      Checks if an ILcdPoint is inside the valid area of geodetic coordinates of the projection. The valid area is determined by the LonLatPoints that are visible and for which the corresponding cartesian coordinate is within the boundaries.
      Parameters:
      aLLP - ILcdPoint to be checked upon.
      Returns:
      true if valid, false if invalid.

    • boundaryLons

      public double[][] boundaryLons(double aLat)
      Description copied from class: ALcdProjection
      Default implementation. To be redefined for specific projections.
      Specified by:
      boundaryLons in interface ILcdProjection
      Overrides:
      boundaryLons in class ALcdProjection
      Parameters:
      aLat - latitude in decimal degrees and -90.0 <= aLat<= 90.0.
      Returns:
      the array of pairs of longitudes[0] and longitudes[1], where the closed interval longitudes[0] -> longitudes[1] is in visible area and -180.0 <= lon[i] <= 180.0.

    • boundaryLats

      public double[][] boundaryLats(double aLon)
      Description copied from class: ALcdProjection
      Default implementation. To be redefined for specific projections.
      Specified by:
      boundaryLats in interface ILcdProjection
      Overrides:
      boundaryLats in class ALcdProjection
      Parameters:
      aLon - longitude in decimal degrees -180.0 <= lon <= 180.0 .
      Returns:
      the array of pairs of latitudes lats[0] and lats[1], where the closed interval lats[0] -> lats[1] is in visible area and -90.0 <= lats[i] <= 90.0 .

    • world2DEditableBoundsOnSphereSFCT

      public void world2DEditableBoundsOnSphereSFCT(double aRadius, ILcd2DEditableBounds aWorldBounds)
      Description copied from interface: ILcdProjection
      Sets the ILcd2DEditableBounds object to the bounds of the projection in world coordinates.
      Parameters:
      aRadius - radius of the sphere.
      aWorldBounds - the bounds of the projection in world coordinates as side effect.

    • inWorldBoundsOnSphere

      public boolean inWorldBoundsOnSphere(ILcdPoint aXYPoint, double aRadius)
      Description copied from interface: ILcdProjection
      Checks if a ILcdPoint is inside the valid cartesian area of the projection. The valid cartesian area is determined naturally by the projection bounds or by an artificial introduced boundary limit because some cartesian points are at infinity. The shape of the valid cartesian area is in many cases rectangular or circular although it might be more complex.
      Parameters:
      aXYPoint - point to be checked upon.
      aRadius - radius of the sphere.
      Returns:
      true if valid, false if invalid.

    • world2DEditableBoundsOnEllipsoidSFCT

      public void world2DEditableBoundsOnEllipsoidSFCT(ILcdEllipsoid aEllipsoid, ILcd2DEditableBounds aWorldBoundsSFCT)
      Description copied from class: ALcdProjection
      Default implementation calls world2lonlatOnSphereSFCT with aEllipsoid.getAuxRadius() as sphere radius.
      Specified by:
      world2DEditableBoundsOnEllipsoidSFCT in interface ILcdProjection
      Overrides:
      world2DEditableBoundsOnEllipsoidSFCT in class ALcdProjection
      Parameters:
      aEllipsoid - ellipsoid considered.
      aWorldBoundsSFCT - the bounds of the projection in world coordinates as side effect.

    • inWorldBoundsOnEllipsoid

      public boolean inWorldBoundsOnEllipsoid(ILcdPoint aXYPoint, ILcdEllipsoid aEllipsoid)
      Description copied from class: ALcdProjection
      Default implementation calls inWorldBoundsOnSphere with aEllipsoid.getAuxRadius() as sphere radius.
      Specified by:
      inWorldBoundsOnEllipsoid in interface ILcdProjection
      Overrides:
      inWorldBoundsOnEllipsoid in class ALcdProjection
      Parameters:
      aXYPoint - point to be checked upon.
      aEllipsoid - ellipsoid on which the geodetic coordinate is defined.
      Returns:
      true if valid, false if invalid.
      See Also:

    • toString

      public String toString()
      Returns the String representation of the transverse mercator projection.
      Specified by:
      toString in interface ILcdProjection
      Overrides:
      toString in class Object
      Returns:
      the String representation of the transverse mercator projection.

    • clone

      public Object clone()
      Description copied from interface: ILcdProjection
      Makes a deep clone of this ILcdProjection.
      Specified by:
      clone in interface ILcdProjection
      Overrides:
      clone in class ALcdTransverseCylindrical
      Returns:
      deep clone of this ILcdProjection.