Package org.orekit.rugged.api

Enum AlgorithmId

java.lang.Object

java.lang.Enum<AlgorithmId>

org.orekit.rugged.api.AlgorithmId

All Implemented Interfaces:

Serializable, Comparable<AlgorithmId>

public enum AlgorithmId
extends Enum<AlgorithmId>

Enumerate for Digital Elevation Model intersection.

Author:

Luc Maisonobe

Enum Constant Summary

Enum Constants

Enum Constant	Description
BASIC_SLOW_EXHAUSTIVE_SCAN_FOR_TESTS_ONLY	Basic, very slow algorithm, designed only for tests and validation purposes.
CONSTANT_ELEVATION_OVER_ELLIPSOID	Algorithm that simply uses a constant elevation over ellipsoid.
DUVENHAGE	Fast algorithm due to Bernardt Duvenhage.
DUVENHAGE_FLAT_BODY	Fast algorithm due to Bernardt Duvenhage.
IGNORE_DEM_USE_ELLIPSOID	Dummy algorithm that simply ignores the Digital Elevation Model.

Method Summary

Modifier and Type	Method	Description
static AlgorithmId	valueOf(String name)	Returns the enum constant of this type with the specified name.
static AlgorithmId[]	values()	Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

DUVENHAGE

public static final AlgorithmId DUVENHAGE

Fast algorithm due to Bernardt Duvenhage.

The algorithm is described in the 2009 paper: Using An Implicit Min/Max KD-Tree for Doing Efficient Terrain Line of Sight Calculations.

DUVENHAGE_FLAT_BODY

public static final AlgorithmId DUVENHAGE_FLAT_BODY

Fast algorithm due to Bernardt Duvenhage.

The algorithm is described in the 2009 paper: Using An Implicit Min/Max KD-Tree for Doing Efficient Terrain Line of Sight Calculations.

This version of the duvenhage's algorithm considers the body to be flat, i.e. lines computed from entry/exit points in the Digital Elevation Model are considered to be straight lines also in geodetic coordinates. The sagitta resulting from real ellipsoid curvature is therefore not corrected in this case. As this computation is not costly (a few percents overhead), the full DUVENHAGE is recommended instead of this one. This choice is mainly intended for comparison purposes with other systems.

BASIC_SLOW_EXHAUSTIVE_SCAN_FOR_TESTS_ONLY

public static final AlgorithmId BASIC_SLOW_EXHAUSTIVE_SCAN_FOR_TESTS_ONLY

Basic, very slow algorithm, designed only for tests and validation purposes.

The algorithm simply computes entry and exit points at high and low altitudes, and scans all Digital Elevation Models in the sub-tiles defined by these two corner points. It is not designed for operational use.

CONSTANT_ELEVATION_OVER_ELLIPSOID

public static final AlgorithmId CONSTANT_ELEVATION_OVER_ELLIPSOID

Algorithm that simply uses a constant elevation over ellipsoid.

Intersections are computed only with respect to the reference ellipsoid and a user-specified elevation. If the user-specified elevation is 0.0, then this algorithm is equivalent to IGNORE_DEM_USE_ELLIPSOID, only slower.

IGNORE_DEM_USE_ELLIPSOID

public static final AlgorithmId IGNORE_DEM_USE_ELLIPSOID

Dummy algorithm that simply ignores the Digital Elevation Model.

Intersections are computed only with respect to the reference ellipsoid.

This algorithm is equivalent to CONSTANT_ELEVATION_OVER_ELLIPSOID when the elevation is set to 0.0, but this one is much faster in this specific case.

Method Detail

values

public static AlgorithmId[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (AlgorithmId c : AlgorithmId.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static AlgorithmId valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null