Class TLcdEckertIV

All Implemented Interfaces:
ILcdCylindrical, ILcdProjection, ILcdPropertyChangeSource, Serializable, Cloneable

public class TLcdEckertIV extends ALcdCylindrical
Eckert IV projection.

Introduction

Pseudocylindrical equal-area projection with elliptical meridians.

Properties

  • Pseudo-cylindrical projection, equal-area.
  • The central meridian is a straight line, 180th meridians are semi-circles.
  • All other meridians are elliptical arcs.
  • Parallels are unequally spaced straight lines.
  • Poles are straight lines half as long as the equator.
  • Scale is true along latitudes 40°30' north and south.

Example

Sample code


 ILcdProjection projection =
     new TLcdEckertIV(0.0);
 

Implementation aspects

The equations of the Eckert IV projection are taken from [Snyder1987].

Since:
V 3.0
See Also:
  • Constructor Details

    • TLcdEckertIV

      public TLcdEckertIV()
      Constructs a Eckert IV projection with the central meridian at 0.
    • TLcdEckertIV

      public TLcdEckertIV(double aCentralMeridian)
      Constructs a Eckert IV projection with a given central meridian.
      Parameters:
      aCentralMeridian - the central meridian for the Eckert IV projection.
  • Method Details

    • 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.
    • lonlatheight2worldOnSphereSFCT

      public void lonlatheight2worldOnSphereSFCT(ILcdPoint aLLHP, double aRadius, ILcd2DEditablePoint aXYPointSFCT) throws TLcdOutOfBoundsException
      Description copied from interface: ILcdProjection
      Transforms an ILcd2DEditablePoint on a sphere into the cartesian coordinate system of the projection.
      Parameters:
      aLLHP - point to be projected.
      aRadius - radius of the sphere (meters).
      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 aLLPointSFCT) 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).
      aLLPointSFCT - 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.
    • inLonLatBounds

      public boolean inLonLatBounds(ILcdPoint aLLHP)
      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:
      aLLHP - ILcdPoint to be checked upon.
      Returns:
      true if valid, false if invalid.
    • 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.
    • 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.
    • boundaryLons

      public double[][] boundaryLons(double aLatitude)
      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:
      aLatitude - 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 aLongitude)
      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:
      aLongitude - 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 .
    • toString

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