org.instantreality.InstantIO
Class Vec2d

java.lang.Object
  org.instantreality.InstantIO.Vec2d

public class Vec2d
extends java.lang.Object

Helper class for exchanging vectors of two double components.

Vec2d is a basic helper class for exchanging vectors of two double components between different software components. It does not contain any means for vector arithmetics, only methods for setting and getting the components. It is not meant to be used directly by software components for vector representation. Instead, software components should use their own, appropriate classes for handling vectors. Only when sending vectors to an OutSlot, or when receiving vectors from an InSlot, the internal representation of vectors should be converted to Vec2d's. This ensures the interoperability between different software components that use different internal representations for vectors.

The following example creates a Vec2d object and prints its components to the console:

 Vec2d vec = new Vec2d(1.0, 2.0);
 System.out.println("x component = " + vec.getX());
 System.out.println("y component = " + vec.getY());
 

Author:

Patrick Dähne

Field Summary

static Vec2d

NULL The null vector <0,0>.

Constructor Summary

Vec2d(double[] vec)
Constructor that initializes the components of the Vec2d object with the values of a given double array.

Vec2d(double x, double y)
Constructor that initializes the components of the Vec2d object with the given double values.

Vec2d(Vec2d vec)
Constructor that initializes the components of the Vec2d object with the components taken from another Vec2d object.

Method Summary

boolean	equals(java.lang.Object obj) Compares the vector to another object.
void	get(double[] vec) Returns the values of the x and y components.
double	getX() Returns the value of the x component.
double	getY() Returns the value of the y component.
java.lang.String	toString() Converts the vector to a string.
static Vec2d	valueOf(java.lang.String str) Converts a string to a Vec2d object.

Methods inherited from class java.lang.Object

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

Field Detail

NULL

public static final Vec2d NULL

The null vector <0,0>.

Constructor Detail

Vec2d

public Vec2d(double x,
             double y)

Constructor that initializes the components of the Vec2d object with the given double values.

The following example demonstrates how to create a Vec2d object:

 double x_component = 1.0;
 double y_component = 2.0;
 Vec2d vec = new Vec2d(x_component, y_component);
 

Parameters:

x - Value of the x component of the new vector.

y - Value of the y component of the new vector.

Vec2d

public Vec2d(double[] vec)

Constructor that initializes the components of the Vec2d object with the values of a given double array.

The following example demonstrates how to create a Vec2d object:

 double x_component = 1.0;
 double y_component = 2.0;
 double[] vector_components = new double[] { x_component, y_component };
 Vec2d vec = new Vec2d(vector_components);
 

Parameters:

vec - An array of at least two double values. The x component of the vector is set to the value of the first element of the array, and the y component is set to the value of the second element of the array.

Vec2d

public Vec2d(Vec2d vec)

Constructor that initializes the components of the Vec2d object with the components taken from another Vec2d object.

The following example demonstrates how to create a Vec2d object that is an exact copy of another Vec2d object:

 Vec2d given_vec = ...;
 Vec2d vec = new Vec2d(given_vec);
 

Parameters:

vec - The other vector used to initialize the new vector.

Method Detail

getX

public final double getX()

Returns the value of the x component.

The following example demonstrates how to print the x component of a Vec2d object to the console:

 Vec2d vec = ...;
 System.out.println("x component = " + vec.getX());
 

Returns:

The value of the x component

getY

public final double getY()

Returns the value of the y component.

The following example demonstrates how to print the y component of a Vec2d object to the console:

 Vec2d vec = ...;
 System.out.println("y component = " + vec.getY());
 

Returns:

The value of the y component

get

public final void get(double[] vec)

Returns the values of the x and y components.

The following example prints the components of a Vec2d object to the console:

 Vec2d vec = ...;
 double[] vector_components = new double[2];
 vec.get(vector_components);
 System.out.println("x component = " + vector_components[0]);
 System.out.println("y component = " + vector_components[1]);
 

Parameters:

vec - A double array that gets filled with the components of the vector. This array must have at least two elements. The first element of the array is set to the x component of the vector, and the second element of the array is set to the y component of the vector.

equals

public final boolean equals(java.lang.Object obj)

Compares the vector to another object. The result is true if the object is not null and is a Vec2d object and the components of the other Vec2d object are the same as the components of this vector.

The following example compares two vectors and prints the result to the console:

 Vec2d vec1 = ...;
 Vec2d vec2 = ...;
 System.out.println("Vectors are the same: " + vec1.equals(vec2));
 

Overrides:

equals in class java.lang.Object

Parameters:

obj - the object to compare the vector to

Returns:

true when the vectors are equal, false otherwise

toString

public final java.lang.String toString()

Converts the vector to a string. The string representation consists of the x component and the y component, separated by space characters.

The following example prints the string representation of a Vec2d object to the console:

 Vec2d vec = ...;
 System.out.println("Vector = " + vec.toString());
 

Overrides:

toString in class java.lang.Object

Returns:

A string representation of the vector

valueOf

public static final Vec2d valueOf(java.lang.String str)

Converts a string to a Vec2d object. The string must consist of the x and y components, separated by space characters.

The following example creates a new Vec2d object:

 Vec2d vec = Vec2d.valueOf("1.0 2.0");
 

Parameters:

str - The string representation of the vector.

Returns:

The new Vec2d object, parsed from the string.