math.geom3d
Class Vector3D

java.lang.Object
  math.geom3d.Vector3D

public class Vector3D
extends java.lang.Object

Define a vector in 3 Dimensions. Provides methods to compute cross product and dot product, addition and subtraction of vectors.

Constructor Summary

Vector3D()
Constructs a new Vector3D initialized with x=1, y=0 and z=0.

Vector3D(double x, double y, double z)
Base constructor, using coordinates in each direction.

Vector3D(Point3D point)
Construct a new vector between origin and a 3D point.

Vector3D(Point3D point1, Point3D point2)
construct a new vector between two points

Method Summary

static Vector3D	crossProduct(Vector3D v1, Vector3D v2) Computes the cross product of the two vectors.
static double	dotProduct(Vector3D v1, Vector3D v2) Computes the dot product of the two vectors, defined by : x1*x2 + y1*y2 + z1*z2 Dot product is zero if the vectors defined by the 2 vectors are orthogonal.
boolean	equals(java.lang.Object obj)
double	getX()
double	getY()
double	getZ()
static boolean	isColinear(Vector3D v1, Vector3D v2) test if the two vectors are colinear
static boolean	isOrthogonal(Vector3D v1, Vector3D v2) test if the two vectors are orthogonal
Vector3D	minus(Vector3D v) Return the subtraction of current vector with vector given as parameter.
double	norm() Computes the norm of the vector
Vector3D	normalize() Returns the vector with same direction as this one, but with norm equal to 1.
double	normSq() Computes the square of the norm of the vector.
Vector3D	opposite() Returns the opposite vector v2 of this, such that the sum of this and v2 equals the null vector.
Vector3D	plus(Vector3D v) Return the sum of current vector with vector given as parameter.
Vector3D	times(double k) Multiplies this vector by a constant.
Vector3D	transform(AffineTransform3D trans) Transform the vector, by using only the first 4 parameters of the transform.

Methods inherited from class java.lang.Object

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

Constructor Detail

Vector3D

public Vector3D()

Constructs a new Vector3D initialized with x=1, y=0 and z=0.

Vector3D

public Vector3D(double x,
                double y,
                double z)

Base constructor, using coordinates in each direction.

Vector3D

public Vector3D(Point3D point)

Construct a new vector between origin and a 3D point.

Vector3D

public Vector3D(Point3D point1,
                Point3D point2)

construct a new vector between two points

Method Detail

dotProduct

public static final double dotProduct(Vector3D v1,
                                      Vector3D v2)

Computes the dot product of the two vectors, defined by :

x1*x2 + y1*y2 + z1*z2

Dot product is zero if the vectors defined by the 2 vectors are orthogonal. It is positive if vectors are in the same direction, and negative if they are in opposite direction.

crossProduct

public static final Vector3D crossProduct(Vector3D v1,
                                          Vector3D v2)

Computes the cross product of the two vectors. Cross product is zero for colinear vectors. It is positive if angle between vector 1 and vector 2 is comprised between 0 and PI, and negative otherwise.

isColinear

public static final boolean isColinear(Vector3D v1,
                                       Vector3D v2)

test if the two vectors are colinear

Returns:

true if the vectors are colinear

isOrthogonal

public static final boolean isOrthogonal(Vector3D v1,
                                         Vector3D v2)

test if the two vectors are orthogonal

Returns:

true if the vectors are orthogonal

getX

public double getX()

getY

public double getY()

getZ

public double getZ()

plus

public Vector3D plus(Vector3D v)

Return the sum of current vector with vector given as parameter. Inner fields are not modified.

minus

public Vector3D minus(Vector3D v)

Return the subtraction of current vector with vector given as parameter. Inner fields are not modified.

times

public Vector3D times(double k)

Multiplies this vector by a constant.

opposite

public Vector3D opposite()

Returns the opposite vector v2 of this, such that the sum of this and v2 equals the null vector.

Returns:

the vector opposite to this.

norm

public double norm()

Computes the norm of the vector

Returns:

the euclidean norm of the vector

normSq

public double normSq()

Computes the square of the norm of the vector. This avoids to compute the square root.

Returns:

the euclidean norm of the vector

normalize

public Vector3D normalize()

Returns the vector with same direction as this one, but with norm equal to 1.

transform

public Vector3D transform(AffineTransform3D trans)

Transform the vector, by using only the first 4 parameters of the transform. Translation of a vector returns the same vector.

Parameters:

trans - an affine transform

Returns:

the transformed vector.

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object