/*
* Copyright (c) 2002-2008 LWJGL Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of 'LWJGL' nor the names of
* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.lwjgl.util.vector;
import java.io.Serializable;
import java.nio.FloatBuffer;
import org.lwjgl.util.vector.Vector2f;
/**
*
* Holds a 2-tuple vector.
*
* @author cix_foo <cix_foo@users.sourceforge.net>
* @version $Revision$
* $Id$
*/
public class Vector2f extends Vector implements Serializable, ReadableVector2f, WritableVector2f {
private static final long serialVersionUID = 1L;
public float x, y;
/**
* Constructor for Vector2f.
*/
public Vector2f() {
super();
}
/**
* Constructor.
*/
public Vector2f(ReadableVector2f src) {
set(src);
}
/**
* Constructor.
*/
public Vector2f(float x, float y) {
set(x, y);
}
/* (non-Javadoc)
* @see org.lwjgl.util.vector.WritableVector2f#set(float, float)
*/
public void set(float x, float y) {
this.x = x;
this.y = y;
}
/**
* Load from another Vector2f
* @param src The source vector
* @return this
*/
public Vector2f set(ReadableVector2f src) {
x = src.getX();
y = src.getY();
return this;
}
/**
* @return the length squared of the vector
*/
public float lengthSquared() {
return x * x + y * y;
}
/**
* Translate a vector
* @param x The translation in x
* @param y the translation in y
* @return this
*/
public Vector2f translate(float x, float y) {
this.x += x;
this.y += y;
return this;
}
/**
* Negate a vector
* @return this
*/
public Vector negate() {
x = -x;
y = -y;
return this;
}
/**
* Negate a vector and place the result in a destination vector.
* @param dest The destination vector or null if a new vector is to be created
* @return the negated vector
*/
public Vector2f negate(Vector2f dest) {
if (dest == null)
dest = new Vector2f();
dest.x = -x;
dest.y = -y;
return dest;
}
/**
* Normalise this vector and place the result in another vector.
* @param dest The destination vector, or null if a new vector is to be created
* @return the normalised vector
*/
public Vector2f normalise(Vector2f dest) {
float l = length();
if (dest == null)
dest = new Vector2f(x / l, y / l);
else
dest.set(x / l, y / l);
return dest;
}
/**
* The dot product of two vectors is calculated as
* v1.x * v2.x + v1.y * v2.y + v1.z * v2.z
* @param left The LHS vector
* @param right The RHS vector
* @return left dot right
*/
public static float dot(Vector2f left, Vector2f right) {
return left.x * right.x + left.y * right.y;
}
/**
* Calculate the angle between two vectors, in radians
* @param a A vector
* @param b The other vector
* @return the angle between the two vectors, in radians
*/
public static float angle(Vector2f a, Vector2f b) {
float dls = dot(a, b) / (a.length() * b.length());
if (dls < -1f)
dls = -1f;
else if (dls > 1.0f)
dls = 1.0f;
return (float)Math.acos(dls);
}
/**
* Add a vector to another vector and place the result in a destination
* vector.
* @param left The LHS vector
* @param right The RHS vector
* @param dest The destination vector, or null if a new vector is to be created
* @return the sum of left and right in dest
*/
public static Vector2f add(Vector2f left, Vector2f right, Vector2f dest) {
if (dest == null)
return new Vector2f(left.x + right.x, left.y + right.y);
else {
dest.set(left.x + right.x, left.y + right.y);
return dest;
}
}
/**
* Subtract a vector from another vector and place the result in a destination
* vector.
* @param left The LHS vector
* @param right The RHS vector
* @param dest The destination vector, or null if a new vector is to be created
* @return left minus right in dest
*/
public static Vector2f sub(Vector2f left, Vector2f right, Vector2f dest) {
if (dest == null)
return new Vector2f(left.x - right.x, left.y - right.y);
else {
dest.set(left.x - right.x, left.y - right.y);
return dest;
}
}
/**
* Store this vector in a FloatBuffer
* @param buf The buffer to store it in, at the current position
* @return this
*/
public Vector store(FloatBuffer buf) {
buf.put(x);
buf.put(y);
return this;
}
/**
* Load this vector from a FloatBuffer
* @param buf The buffer to load it from, at the current position
* @return this
*/
public Vector load(FloatBuffer buf) {
x = buf.get();
y = buf.get();
return this;
}
/* (non-Javadoc)
* @see org.lwjgl.vector.Vector#scale(float)
*/
public Vector scale(float scale) {
x *= scale;
y *= scale;
return this;
}
/* (non-Javadoc)
* @see java.lang.Object#toString()
*/
public String toString() {
StringBuilder sb = new StringBuilder(64);
sb.append("Vector2f[");
sb.append(x);
sb.append(", ");
sb.append(y);
sb.append(']');
return sb.toString();
}
/**
* @return x
*/
public final float getX() {
return x;
}
/**
* @return y
*/
public final float getY() {
return y;
}
/**
* Set X
* @param x
*/
public final void setX(float x) {
this.x = x;
}
/**
* Set Y
* @param y
*/
public final void setY(float y) {
this.y = y;
}
public boolean equals(Object obj) {
if (this == obj) return true;
if (obj == null) return false;
if (getClass() != obj.getClass()) return false;
Vector2f other = (Vector2f)obj;
if (x == other.x && y == other.y) return true;
return false;
}
}