Class CylindricalEqualArea

All Implemented Interfaces:
Serializable, Parameterized, LenientComparable, org.opengis.referencing.operation.MathTransform, org.opengis.referencing.operation.MathTransform2D
Direct Known Subclasses:
CylindricalEqualArea.Spherical

public class CylindricalEqualArea extends AuthalicConversion
Cylindrical Equal Area projection (EPSG codes 9834, 9835). This is the simplest equal-area projection. This projection has various names depending on its standard parallel:
Non-exhaustive list of variants
Name Standard parallel
Lambert cylindrical equal-area
Behrmann cylindrical equal-area 30°
Gall orthographic 45°
Balthasart 50°

Description

The parallels and the meridians are straight lines and cross at right angles. The scale is true along standard parallels, but distortion increase greatly at other locations. Distortions are so great that there is little use of this projection for world mapping purposes. However, this projection may be useful for computing areas.
Since:
0.8
Version:
1.2
See Also:
  • Field Details

  • Constructor Details

    • CylindricalEqualArea

      public CylindricalEqualArea(org.opengis.referencing.operation.OperationMethod method, Parameters parameters)
      Creates a Cylindrical Equal Area projection from the given parameters.
      Parameters:
      method - Description of the projection parameters.
      parameters - The parameter values of the projection to create.
    • CylindricalEqualArea

      @Workaround(library="JDK", version="1.7") private CylindricalEqualArea(Initializer initializer)
      Work around for RFE #4093999 in Sun's bug database ("Relax constraint on placement of this()/super() call in constructors").
    • CylindricalEqualArea

      CylindricalEqualArea(CylindricalEqualArea other)
      Creates a new projection initialized to the same parameters than the given one.
  • Method Details

    • initializer

      @Workaround(library="JDK", version="1.7") private static Initializer initializer(org.opengis.referencing.operation.OperationMethod method, Parameters parameters)
      Work around for RFE #4093999 in Sun's bug database ("Relax constraint on placement of this()/super() call in constructors").
    • createMapProjection

      public org.opengis.referencing.operation.MathTransform createMapProjection(org.opengis.referencing.operation.MathTransformFactory factory) throws org.opengis.util.FactoryException
      Returns the sequence of normalizationthisdenormalization transforms as a whole. The transform returned by this method expects (longitude, latitude) coordinates in degrees and returns (x,y) coordinates in metres.

      The non-linear part of the returned transform will be this transform, except if the ellipsoid is spherical. In the latter case, this transform may be replaced by a simplified implementation.

      Overrides:
      createMapProjection in class NormalizedProjection
      Parameters:
      factory - the factory to use for creating the transform.
      Returns:
      the map projection from (λ,φ) to (x,y) coordinates.
      Throws:
      org.opengis.util.FactoryException - if an error occurred while creating a transform.
      See Also:
    • transform

      public org.opengis.referencing.operation.Matrix transform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, boolean derivate) throws ProjectionException
      Projects the specified (λ,φ) coordinates (units in radians) and stores the result in dstPts. In addition, opportunistically computes the projection derivative if derivate is true. The results must be multiplied by the denormalization matrix before to get linear distances.
      Specified by:
      transform in class NormalizedProjection
      Parameters:
      srcPts - the array containing the source point coordinates, as (longitude, latitude) angles in radians.
      srcOff - the offset of the single coordinate tuple to be converted in the source array.
      dstPts - the array into which the converted coordinates is returned (may be the same than srcPts). Coordinates will be expressed in a dimensionless unit, as a linear distance on a unit sphere or ellipse.
      dstOff - the offset of the location of the converted coordinates that is stored in the destination array.
      derivate - true for computing the derivative, or false if not needed.
      Returns:
      the matrix of the projection derivative at the given source position, or null if the derivate argument is false.
      Throws:
      ProjectionException - if the coordinates cannot be converted.
      See Also:
    • transform

      public void transform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) throws org.opengis.referencing.operation.TransformException
      Converts a list of coordinate tuples. This method performs the same calculation than above transform(double[], int, double[], int, boolean) method, but is overridden for efficiency.
      Specified by:
      transform in interface org.opengis.referencing.operation.MathTransform
      Overrides:
      transform in class AbstractMathTransform
      Parameters:
      srcPts - the array containing the source point coordinates.
      srcOff - the offset to the first point to be transformed in the source array.
      dstPts - the array into which the transformed point coordinates are returned. May be the same than srcPts.
      dstOff - the offset to the location of the first transformed point that is stored in the destination array.
      numPts - the number of point objects to be transformed.
      Throws:
      org.opengis.referencing.operation.TransformException - if a point cannot be converted.
    • inverseTransform

      protected void inverseTransform(double[] srcPts, int srcOff, double[] dstPts, int dstOff) throws ProjectionException
      Converts the specified (x,y) coordinates and stores the result in dstPts (angles in radians).
      Specified by:
      inverseTransform in class NormalizedProjection
      Parameters:
      srcPts - the array containing the source point coordinates, as linear distance on a unit sphere or ellipse.
      srcOff - the offset of the point to be converted in the source array.
      dstPts - the array into which the converted point coordinates is returned (may be the same than srcPts). Coordinates will be (longitude, latitude) angles in radians.
      dstOff - the offset of the location of the converted point that is stored in the destination array.
      Throws:
      ProjectionException - if the point cannot be converted.