Mega Code Archive
Vector2 Structure
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/*
* This file is part of Libgdx by Mario Zechner (badlogicgames@gmail.com)
*
* Libgdx is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Libgdx is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with libgdx. If not, see <http://www.gnu.org/licenses/>.
*/
//package com.badlogic.gdx.math;
/**
* Taken from libgdx
* Modified to remove final declaration
*
* Encapsulates a 2D vector. Allows chaining methods by returning a
* reference to itself
* @author badlogicgames@gmail.com
*
*/
public class Vector2
{
/** static temporary vector **/
private final static Vector2 tmp = new Vector2();
/** the x-component of this vector **/
public float x;
/** the y-component of this vector **/
public float y;
/**
* Constructs a new vector at (0,0)
*/
public Vector2( )
{
}
/**
* Constructs a vector with the given components
* @param x The x-component
* @param y The y-component
*/
public Vector2( float x, float y )
{
this.x = x;
this.y = y;
}
/**
* Constructs a vector from the given vector
* @param v The vector
*/
public Vector2( Vector2 v )
{
set( v );
}
/**
* @return a copy of this vector
*/
public Vector2 cpy( )
{
return new Vector2( this );
}
/**
* @return The euclidian length
*/
public float len( )
{
return (float)Math.sqrt( x * x + y * y );
}
/**
* @return The squared euclidian length
*/
public float len2( )
{
return x * x + y * y;
}
/**
* Sets this vector from the given vector
* @param v The vector
* @return This vector for chaining
*/
public Vector2 set( Vector2 v )
{
x = v.x;
y = v.y;
return this;
}
/**
* Sets the components of this vector
* @param x The x-component
* @param y The y-component
* @return This vector for chaining
*/
public Vector2 set( float x, float y )
{
this.x = x;
this.y = y;
return this;
}
/**
* Substracts the given vector from this vector.
* @param v The vector
* @return This vector for chaining
*/
public Vector2 sub( Vector2 v )
{
x -= v.x;
y -= v.y;
return this;
}
/**
* Normalizes this vector
* @return This vector for chaining
*/
public Vector2 nor( )
{
float len = len( );
if( len != 0 )
{
x /= len;
y /= len;
}
return this;
}
/**
* Adds the given vector to this vector
* @param v The vector
* @return This vector for chaining
*/
public Vector2 add( Vector2 v )
{
x += v.x;
y += v.y;
return this;
}
/**
* Adds the given components to this vector
* @param x The x-component
* @param y The y-component
* @return This vector for chaining
*/
public Vector2 add( float x, float y )
{
this.x += x;
this.y += y;
return this;
}
/**
* @param v The other vector
* @return The dot product between this and the other vector
*/
public float dot( Vector2 v )
{
return x * v.x + y * v.y;
}
/**
* Multiplies this vector by a scalar
* @param scalar The scalar
* @return This vector for chaining
*/
public Vector2 mul( float scalar )
{
x *= scalar;
y *= scalar;
return this;
}
/**
* @param v The other vector
* @return the distance between this and the other vector
*/
public float dst(Vector2 v)
{
float x_d = v.x - x;
float y_d = v.y - y;
return (float)Math.sqrt( x_d * x_d + y_d * y_d );
}
/**
* @param x The x-component of the other vector
* @param y The y-component of the other vector
* @return the distance between this and the other vector
*/
public float dst( float x, float y )
{
float x_d = x - this.x;
float y_d = y - this.y;
return (float)Math.sqrt( x_d * x_d + y_d * y_d );
}
/**
* @param v The other vector
* @return the squared distance between this and the other vector
*/
public float dst2(Vector2 v)
{
float x_d = v.x - x;
float y_d = v.y - y;
return x_d * x_d + y_d * y_d;
}
public String toString( )
{
return "[" + x + ":" + y + "]";
}
/**
* Substracts the other vector from this vector.
* @param x The x-component of the other vector
* @param y The y-component of the other vector
* @return This vector for chaining
*/
public Vector2 sub(float x, float y)
{
this.x -= x;
this.y -= y;
return this;
}
/**
* @return a temporary copy of this vector. Use with care as this is backed by a single static Vector2 instance. v1.tmp().add( v2.tmp() ) will not work!
*/
public Vector2 tmp( )
{
return tmp.set(this);
}
}
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