org.freehep.graphics3d
Class Quaternion

java.lang.Object
  |
  +--org.freehep.graphics3d.Quaternion

public class Quaternion

extends Object

Keeps a quaternion.

Original ArcBall C code from Ken Shoemake, Graphics Gems IV, 1993.

Version:

$Id: Quaternion.java,v 1.3 2003/03/20 00:20:23 duns Exp $

Author:

Mark Donszelmann

Field Summary

double	w
double	x
double	y
double	z

Constructor Summary

Quaternion()
creates a null quaternion

Quaternion(double x, double y, double z, double w)
creates a quaternion from x,y,z,w

Quaternion(Quaternion q)
creates a new quaternion from q

Method Summary

Quaternion	conjugate(Quaternion r)
double	length()
Quaternion	multiply(Quaternion q, Quaternion r)
Quaternion	normalize(Quaternion r)
Quaternion	set(double x, double y, double z, double w)
Quaternion	set(Quaternion q)
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

x

public double x

y

public double y

z

public double z

w

public double w

Constructor Detail

Quaternion

public Quaternion(double x,
                  double y,
                  double z,
                  double w)

creates a quaternion from x,y,z,w

Quaternion

public Quaternion()

creates a null quaternion

Quaternion

public Quaternion(Quaternion q)

creates a new quaternion from q

Method Detail

toString

public String toString()

Overrides:

toString in class Object

Returns:

a string representation of quaternion

length

public double length()

Returns:

length of quaternion

normalize

public Quaternion normalize(Quaternion r)

Returns:

normalized form of quaternion, or null if length is 0;

multiply

public Quaternion multiply(Quaternion q,
                           Quaternion r)

Returns:

quaternion product (this * q). Note: order is important! To combine rotations, use the product this.multiply(q), which gives the effect of rotating by this then q.

conjugate

public Quaternion conjugate(Quaternion r)

Returns:

conjugate of quaternion.

set

public Quaternion set(double x,
                      double y,
                      double z,
                      double w)

Returns:

the quaternion set to x,y,z,w

set

public Quaternion set(Quaternion q)

Returns:

the quaternion set to q