Package com.luciad.projection

Class TLcdAlbersEqualAreaConic

java.lang.Object
com.luciad.projection.ALcdProjection
com.luciad.projection.ALcdConic
com.luciad.projection.TLcdAlbersEqualAreaConic
All Implemented Interfaces:
ILcdConic, ILcdProjection, ILcdPropertyChangeSource, Serializable, Cloneable
public class TLcdAlbersEqualAreaConic extends ALcdConic
Albers Equal Area Conic projection.

Introduction

The Albers equal-area conic projection is a conic map projection which superimposes a cone over the sphere of the Earth, with two reference parallels secant to the globe and intersecting it.

Properties

  • Equal-area.
  • The scale of the projection is true along two standard parallels.
  • Parallels are unequally spaced arcs of concentric circles and meridians are equally spaced radii cutting parallels at right angles.
  • Used for equal-area maps of regions with dominant east-west shape.

Example

Sample code


 ILcdProjection projection =
     new TLcdAlbersEqualAreaConic(29.0, 45.5, 0.0, 50.0);

Implementation aspects

The equations of the albers equal area conic projection are taken from [Snyder1987].

See Also:

  • Constructor Details

    • TLcdAlbersEqualAreaConic

      public TLcdAlbersEqualAreaConic()
      Default constructor.

    • TLcdAlbersEqualAreaConic

      public TLcdAlbersEqualAreaConic(double aFirstParallel, double aSecondParallel, double aOriginLongitude, double aOriginLatitude)
      Constructs an Albers Equal Area Conic projection with the specified properties.
      Parameters:
      aFirstParallel - the value for the firstParallel property.
      aSecondParallel - the value for the secondParallel property.
      aOriginLongitude - the value for the originLongitude property.
      aOriginLatitude - the value for the originLatitude property.

  • Method Details

    • calculateCachedValues

      protected void calculateCachedValues()
      Description copied from class: ALcdConic
      Constants based on the point of origin of the projection and the two standard parallels 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 ALcdConic

    • 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.

    • lonlatheight2worldOnEllipsoidSFCT

      public void lonlatheight2worldOnEllipsoidSFCT(ILcdPoint aLLHP, ILcdEllipsoid aEllipsoid, ILcd2DEditablePoint aXYPointSFCT) throws TLcdOutOfBoundsException
      Description copied from class: ALcdProjection
      Default implementation calls lonlatheight2worldOnEllipsoidSFCT with aEllipsoid.getAuxRadius() as sphere radius.
      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.

    • 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 lat)
      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:
      lat - 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 lon)
      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:
      lon - 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 aWorldBound)
      Description copied from interface: ILcdProjection
      Sets the ILcd2DEditableBounds object to the bounds of the projection in world coordinates.
      Parameters:
      aRadius - radius of the sphere.
      aWorldBound - 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 aWorldBound)
      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.
      aWorldBound - 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 Albers equal area conic projection.
      Specified by:
      toString in interface ILcdProjection
      Overrides:
      toString in class Object
      Returns:
      the String representation of the Albers equal area conic 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 ALcdConic
      Returns:
      deep clone of this ILcdProjection.