Class LambertConicConformal

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

public class LambertConicConformal extends ConformalProjection
Lambert Conic Conformal projection (EPSG codes 9801, 9802, 9803, 9826, 1051). See the following references for an overview:

Description

Areas and shapes are deformed as one moves away from standard parallels. The angles are true in a limited area. This projection is used for the charts of North America and some European countries.
Since:
0.6
Version:
1.3
See Also:
  • Field Details

    • serialVersionUID

      private static final long serialVersionUID
      For cross-version compatibility.
      See Also:
    • n

      final double n
      Internal coefficients for computation, depending only on eccentricity and values of standards parallels. This is defined as n = (ln m₁ – ln m₂) / (ln t₁ – ln t₂) in §1.3.1.1 of IOGP Publication 373-7-2 – Geomatics Guidance Note number 7, part 2 – April 2015.

      Note:

      • If φ₁ = -φ₂, then the cone become a cylinder and this n value become 0. This limiting case is the Mercator projection, but we cannot use this class because n=0 causes indetermination like 0 × ∞ in the equations of this class.
      • If φ₁ = φ₂ = ±90°, then this n value become ±1. The formulas in the transform and inverse transform methods become basically the same than the ones in PolarStereographic, but (de)normalization matrices contain NaN values.
      • Depending on how the formulas are written, n may be positive in the South hemisphere and negative in the North hemisphere (or conversely). However, Apache SIS adjusts the coefficients of the (de)normalization matrices in order to keep n positive, because the formulas are slightly more accurate for positive n values. However, this adjustment is optional and can be disabled in the constructor.
  • Constructor Details

    • LambertConicConformal

      public LambertConicConformal(org.opengis.referencing.operation.OperationMethod method, Parameters parameters)
      Creates a Lambert projection from the given parameters. The method argument can be the description of one of the following:
      • "Lambert Conic Conformal (1SP)".
      • "Lambert Conic Conformal (West Orientated)".
      • "Lambert Conic Conformal (2SP)".
      • "Lambert Conic Conformal (2SP Belgium)".
      • "Lambert Conic Conformal (2SP Michigan)".
      Parameters:
      method - description of the projection parameters.
      parameters - the parameter values of the projection to create.
    • LambertConicConformal

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

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

    • belgeA

      static Number belgeA()
      Constant for the Belgium 2SP case. Defined as 29.2985 seconds, given here in radians. Use double-double arithmetic not for map projection accuracy, but for consistency with the normalization matrix which use that precision for "degrees to radians" conversion. The goal is to have cleaner results after matrix inversions and multiplications.
      Tip: how to verify the value:
    • 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").
    • getInternalParameterNames

      final String[] getInternalParameterNames()
      Returns the names of additional internal parameters which need to be taken in account when comparing two LambertConicConformal projections or formatting them in debug mode.
      Overrides:
      getInternalParameterNames in class NormalizedProjection
    • getInternalParameterValues

      final double[] getInternalParameterValues()
      Returns the values of additional internal parameters which need to be taken in account when comparing two LambertConicConformal projections or formatting them in debug mode.
      Overrides:
      getInternalParameterValues in class NormalizedProjection
    • 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:
    • getDomain

      public Optional<org.opengis.geometry.Envelope> getDomain(DomainDefinition criteria)
      Returns the domain of input coordinates. The limits defined by this method are arbitrary and may change in any future implementation. Current implementation sets a longitude range of ±180° (i.e. the world) and a latitude range from pole to equator in the hemisphere of the projection.
      Overrides:
      getDomain in class AbstractMathTransform
      Parameters:
      criteria - controls the definition of transform domain.
      Returns:
      estimation of a domain where this transform is considered numerically applicable.
      Since:
      1.3
      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 (θ,φ) coordinates and stores the result in dstPts. In addition, opportunistically computes the projection derivative if derivate is true. The units of measurement are implementation-specific (see super-class javadoc). 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:
    • inverseTransform

      protected void inverseTransform(double[] srcPts, int srcOff, double[] dstPts, int dstOff) throws ProjectionException
      Converts the specified (x,y) coordinates and stores the (θ,φ) result in dstPts.
      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.