/*
 * $RCSfile$
 *
 * Copyright (c) 2004 Sun Microsystems, Inc. All rights reserved.
 *
 * Use is subject to license terms.
 *
 * $Revision$
 * $Date$
 * $State$
 */

package javax.vecmath;

import java.lang.Math;

/**
 * A three byte tuple.  Note that Java defines a byte as a signed integer
 * in the range [-128, 127]. However, colors are more typically
 * represented by values in the range [0, 255]. Java 3D recognizes this
 * and, in those cases where Tuple3b is used to represent color, treats
 * the bytes as if the range were [0, 255]---in other words, as if the
 * bytes were unsigned.
 * Values greater than 127 can be assigned to a byte variable using a
 * type cast.  For example:
 * <ul>byteVariable = (byte) intValue; // intValue can be > 127</ul>
 * If intValue is greater than 127, then byteVariable will be negative.  The
 * correct value will be extracted when it is used (by masking off the upper
 * bits).
 */
public abstract class Tuple3b implements java.io.Serializable, Cloneable {

    static final long serialVersionUID = -483782685323607044L;

    /**
     * The first value.
     */
    public	byte	x;

    /**
     * The second value.
     */
    public	byte	y;

    /**
     * The third value.
     */
    public	byte	z;


    /**
     * Constructs and initializes a Tuple3b from the specified three values.
     * @param b1 the first value
     * @param b2 the second value
     * @param b3 the third value
     */
    public Tuple3b(byte b1, byte b2, byte b3)
    {
	this.x = b1;
	this.y = b2;
	this.z = b3;
    }


    /**
     * Constructs and initializes a Tuple3b from input array of length 3.
     * @param t the array of length 3 containing b1 b2 b3 in order
     */
    public Tuple3b(byte[] t)
    {
	this.x = t[0];
	this.y = t[1];
	this.z = t[2];
    }


    /**
     * Constructs and initializes a Tuple3b from the specified Tuple3b.
     * @param t1  the Tuple3b containing the initialization x y z data
     */
    public Tuple3b(Tuple3b t1)
    {
	this.x = t1.x;
	this.y = t1.y;
	this.z = t1.z;
    }


    /**
     * Constructs and initializes a Tuple3b to (0,0,0).
     */
    public Tuple3b()
    {
	this.x = (byte) 0;
	this.y = (byte) 0;
	this.z = (byte) 0;
    }


   /**
     * Returns a string that contains the values of this Tuple3b.
     * @return a String with the values
     */
    public String toString()
    {   
        return("("  + ((int)this.x & 0xff) +
	       ", " + ((int)this.y & 0xff) +
	       ", " + ((int)this.z & 0xff) + ")");
    }   

 
   /**   
     * Places the value of the x,y,z components of this Tuple3b
     * into the array of length 3.
     * @param t array of length 3 into which the component values are copied
     */ 
    public final void get(byte[] t)
    {   
 
        t[0] = this.x;
        t[1] = this.y;
        t[2] = this.z;
    }   


   /**
     * Places the value of the x,y,z components of this tuple into 
     * the tuple t1.
     * @param t1  the tuple into which the values are placed
     */
    public final void get(Tuple3b t1)
    {
       t1.x = this.x;
       t1.y = this.y;
       t1.z = this.z;
    }


   /**
     * Sets the value of the data members of this tuple to the value 
     * of the argument tuple t1.
     * @param t1  the source tuple for the memberwise copy
     */ 
    public final void set(Tuple3b t1)
    {   
        this.x = t1.x;
        this.y = t1.y;
        this.z = t1.z;
    }   

 
   /**
     * Sets the value of the x,y,z, data members of this tuple to the 
     * values in the array t of length 3.
     * @param t  array of length 3 which is the source for the memberwise copy
     */ 
    public final void set(byte[] t)
    {   
        this.x = t[0];
        this.y = t[1];
        this.z = t[2];
    }   

 
   /**
     * Returns true if all of the data members of tuple t1 are equal to
     * the corresponding data members in this tuple. 
     * @param t1  the tuple with which the comparison is made
     * @return  true or false
     */ 
    public boolean equals(Tuple3b t1)
    {
        try {
        return(this.x == t1.x && this.y == t1.y && this.z == t1.z);
        }
        catch (NullPointerException e2) {return false;}

    }

   /**
     * Returns true if the Object t1 is of type Tuple3b and all of the
     * data members of t1 are equal to the corresponding data members in
     * this Tuple3b.
     * @param t1  the object with which the comparison is made
     */ 
    public boolean equals(Object t1)
    {
        try {
           Tuple3b t2 = (Tuple3b) t1;
           return(this.x == t2.x && this.y == t2.y && this.z == t2.z);
        }
        catch (NullPointerException e2) {return false;}
        catch (ClassCastException   e1) {return false;}

    }

    /**
     * Returns a hash code value based on the data values in this
     * object.  Two different Tuple3b objects with identical data values
     * (i.e., Tuple3b.equals returns true) will return the same hash
     * code value.  Two objects with different data members may return the
     * same hash value, although this is not likely.
     * @return the integer hash code value
     */  
    public int hashCode() {
	return ((((int)x & 0xff) <<  0) |
		(((int)y & 0xff) <<  8) |
		(((int)z & 0xff) << 16));
    }
   
    /**
     * Creates a new object of the same class as this object.
     *
     * @return a clone of this instance.
     * @exception OutOfMemoryError if there is not enough memory.
     * @see java.lang.Cloneable
     * @since Java 3D 1.3
     */
    public Object clone() {
	// Since there are no arrays we can just use Object.clone()
	try {
	    return super.clone();
	} catch (CloneNotSupportedException e) {
	    // this shouldn't happen, since we are Cloneable
	    throw new InternalError();
	}
    }

}