cds.astro
Class Coocube

java.lang.Object
  cds.astro.Coo
      cds.astro.Coocube

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

public class Coocube
extends Coo

The routines provided in this module define a "coordinate" as a face number (between 1 and 6), and two (X,Y) values in the range [-1,1[ representing the projection of a direction onto a cube. The face numbers, and the axis orientations, are:

 1 = +z X=+y Y=-x  (North Pole)
 2 = +y X=-z Y=-x  (azimuth +90)
 3 = +x X=+y Y=+z  (azimuth 0)
 4 = -x X=-z Y=-y  (azimuth 180)
 5 = -y X=+x Y=+z  (azimuth -90)
 6 = -z X=+x Y=-y  (South Pole)
           +---------+
           |    ^    |
           |    |x   |
           |<---+    |
           |    1    |
 +---------+---------+---------+---------+
 |    ^    |    ^    |         |         |
 |    |    |    |    |         |         |
 |   5+--->|  3 +--->|   2+--->|   4+--->|
 |      x  |      x  |   x|    |   x|    |
 |         |         |    v    |    v    |
 +---------+---------+---------+---------+
           |    ^    |
           |    |x   |
           |<---+    |
           |    6    |
           +---------+

These coordinates can be used to address accurately a point with 2 floating-point numbers associated to a 3-bit face number

Version:

1.0 16-sep-2002

Author:

Francois Ochsenbein

See Also:

Serialized Form

Field Summary

byte	face The face number in range 1 to 6 -- zero for undefined.
double	X The position on the face, a number between -1 and 1.
double	Y The position on the face, a number between -1 and 1.

Fields inherited from class cds.astro.Coo

decimals, ed, Umatrix3, x, y, z

Constructor Summary

Coocube()
Define the default undefined Coocube

Coocube(Coo coo)
Define the Coocube from a Coordinate

Coocube(int face, double X, double Y)
Define the Coocube from its components

Method Summary

java.lang.StringBuffer	edit(java.lang.StringBuffer buf, int ndec) Edit the Coocube value as f:±X±Y
static int	face(double[] u) Compute the face number from the unit vector
void	set(Coo coo) Compute the Coocube coordinates
void	set(double[] u) Compute the Coocube coordinates from the Direction Cosines
void	set(int face, double X, double Y) Compute the Coocube from its (XY) components
static int	setUvec(int face, double X, double Y, double[] u) Transformation (face + Projections) --> unit vector
static int	setXY(double[] u, double[] XY) Compute the (face, X, Y)
java.lang.String	toString() Default Edition of the Coocube values

Methods inherited from class cds.astro.Coo

add, add, clone, copyAngles, copyUvector, distance, distance, dump, editCoo, equals, eulerMatrix, getLat, getLon, localMatrix, localMatrix, localMatrix, moveMatrix, normalize, normalize, parse, parsing, rotate_1, rotate, rotateVector_1, rotateVector, set, set, set, set, setDecimals, setUvec, sub, sub

Methods inherited from class java.lang.Object

getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

face

public byte face

The face number in range 1 to 6 -- zero for undefined.

X

public double X

The position on the face, a number between -1 and 1.

Y

public double Y

The position on the face, a number between -1 and 1.

Constructor Detail

Coocube

public Coocube()

Define the default undefined Coocube

Coocube

public Coocube(Coo coo)

Define the Coocube from a Coordinate

Coocube

public Coocube(int face,
               double X,
               double Y)

Define the Coocube from its components

Parameters:

face - the face number between 1 and 6 face is set to 0 in case of error.

X - x position on the face

Y - y position on the face

Method Detail

face

public static final int face(double[] u)

Compute the face number from the unit vector

Parameters:

u - unit vector (vector of 3 direction cosines)

Returns:

the face number in range 1..6 (0 if error)

setXY

public static final int setXY(double[] u,
                              double[] XY)

Compute the (face, X, Y)

Parameters:

u - the Direction Cosines

XY - the (X,Y) components

Returns:

the face number in range 1..6 (0 if error)

setUvec

public static final int setUvec(int face,
                                double X,
                                double Y,
                                double[] u)

Transformation (face + Projections) --> unit vector

Parameters:

face - the face number (1 to 6)

X - X value of the projection on the face n

Y - Y value of the projection on the face n

u - the unit vector (modified)

Returns:

the face number

set

public final void set(double[] u)

Compute the Coocube coordinates from the Direction Cosines

Parameters:

u - the Direction Cosines

set

public final void set(Coo coo)

Compute the Coocube coordinates

Overrides:

set in class Coo

Parameters:

coo - coordinates of a point

set

public final void set(int face,
                      double X,
                      double Y)

Compute the Coocube from its (XY) components

Parameters:

face - the face number between 1 and 6 face is set to 0 in case of error.

X - x position on the face

Y - y position on the face

edit

public java.lang.StringBuffer edit(java.lang.StringBuffer buf,
                                   int ndec)

Edit the Coocube value as f:±X±Y

Overrides:

edit in class Coo

Parameters:

buf - buffer for the edition

ndec - number of decimals for edition (a value of 6 corresponds to an accuracy of 0.3arcsec)

Returns:

the face number in range 1..6 (0 if error)

toString

public java.lang.String toString()

Default Edition of the Coocube values

Overrides:

toString in class Coo

Returns:

the string equivalent of the Coocube the angles in degrees.