Package org.apache.sis.referencing.operation.projection

Class Orthographic

java.lang.Object

org.apache.sis.io.wkt.FormattableObject

org.apache.sis.referencing.operation.transform.AbstractMathTransform

org.apache.sis.referencing.operation.transform.AbstractMathTransform2D

org.apache.sis.referencing.operation.projection.NormalizedProjection

org.apache.sis.referencing.operation.projection.Orthographic

All Implemented Interfaces:

Serializable, Parameterized, LenientComparable, org.opengis.referencing.operation.MathTransform, org.opengis.referencing.operation.MathTransform2D

public class Orthographic
extends NormalizedProjection

Orthographic projection (EPSG:9840). See the following references for an overview:

• Orthographic projection on Wikipedia
• Orthographic projection on MathWorld

Description

This is a perspective azimuthal (planar) projection that is neither conformal nor equal-area. It resembles a globe viewed from a point of perspective at infinite distance. Only one hemisphere can be seen at a time. While not useful for accurate measurements, this projection is useful for pictorial views of the world.

Since:

1.1

Version:

1.1

Author:

Rueben Schulz (UBC), Martin Desruisseaux (Geomatys), Rémi Maréchal (Geomatys)

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.sis.referencing.operation.projection.NormalizedProjection

NormalizedProjection.ParameterRole

Field Summary

Fields inherited from class org.apache.sis.referencing.operation.projection.NormalizedProjection

eccentricity, eccentricitySquared

Fields inherited from class org.apache.sis.referencing.operation.transform.AbstractMathTransform2D

DIMENSION

Constructor Summary

Constructors

Constructor	Description
Orthographic(org.opengis.referencing.operation.OperationMethod method, Parameters parameters)	Creates an orthographic projection from the given parameters.

Method Summary

Modifier and Type	Method	Description
protected void	inverseTransform(double[] srcPts, int srcOff, double[] dstPts, int dstOff)	Converts the specified (x,y) coordinates and stores the result in dstPts (angles in radians).
org.opengis.referencing.operation.Matrix	transform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, boolean derivate)	Projects the specified (λ,φ) coordinates and stores the result in dstPts.

Methods inherited from class org.apache.sis.referencing.operation.projection.NormalizedProjection

computeHashCode, createMapProjection, equals, getContextualParameters, getParameterDescriptors, getParameterValues, inverse, tryConcatenate

Methods inherited from class org.apache.sis.referencing.operation.transform.AbstractMathTransform2D

createTransformedShape, derivative, getSourceDimensions, getTargetDimensions, transform

Methods inherited from class org.apache.sis.referencing.operation.transform.AbstractMathTransform

derivative, equals, formatTo, getDomain, hashCode, isIdentity, transform, transform, transform, transform, transform

Methods inherited from class org.apache.sis.io.wkt.FormattableObject

print, toString, toString, toWKT

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.opengis.referencing.operation.MathTransform

derivative, isIdentity, toWKT, transform, transform, transform, transform, transform

Constructor Details

Orthographic

public Orthographic(org.opengis.referencing.operation.OperationMethod method,
 Parameters parameters)

Creates an orthographic projection from the given parameters. The method argument can be the description of one of the following:

• "Orthographic".

Parameters:

method - description of the projection parameters.

parameters - the parameter values of the projection to create.

Method Details

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 and stores the result in dstPts. 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:

• AbstractMathTransform.derivative(DirectPosition)
• AbstractMathTransform.transform(DirectPosition, DirectPosition)
• MathTransforms.derivativeAndTransform(MathTransform, double[], int, double[], int)

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.