/*
  * Copyright (c) 2006-2007 Erin Catto 
* This software is provided 'as-is', without any express or implied
* warranty.  In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked, and must not be
* misrepresented the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/

// b2Vec2 has no constructor so that it
// can be placed in a union.
var b2Vec2 = Class.create();
b2Vec2.prototype = 
{
        initialize: function(x_, y_) {this.x=x_; this.y=y_;},

        SetZero: function() { this.x = 0.0; this.y = 0.0; },
        Set: function(x_, y_) {this.x=x_; this.y=y_;},
        SetV: function(v) {this.x=v.x; this.y=v.y;},

        Negative: function(){ return new b2Vec2(-this.x, -this.y); },

        Copy: function(){
                return new b2Vec2(this.x,this.y);
        },

        Add: function(v)
        {
                this.x += v.x; this.y += v.y;
        },

        Subtract: function(v)
        {
                this.x -= v.x; this.y -= v.y;
        },

        Multiply: function(a)
        {
                this.x *= a; this.y *= a;
        },

        MulM: function(A)
        {
                var tX = this.x;
                this.x = A.col1.x * tX + A.col2.x * this.y;
                this.y = A.col1.y * tX + A.col2.y * this.y;
        },

        MulTM: function(A)
        {
                var tX = b2Math.b2Dot(this, A.col1);
                this.y = b2Math.b2Dot(this, A.col2);
                this.x = tX;
        },

        CrossVF: function(s)
        {
                var tX = this.x;
                this.x = s * this.y;
                this.y = -s * tX;
        },

        CrossFV: function(s)
        {
                var tX = this.x;
                this.x = -s * this.y;
                this.y = s * tX;
        },

        MinV: function(b)
        {
                this.x = this.x < b.x ? this.x : b.x;
                this.y = this.y < b.y ? this.y : b.y;
        },

        MaxV: function(b)
        {
                this.x = this.x > b.x ? this.x : b.x;
                this.y = this.y > b.y ? this.y : b.y;
        },

        Abs: function()
        {
                this.x = Math.abs(this.x);
                this.y = Math.abs(this.y);
        },

        Length: function()
        {
                return Math.sqrt(this.x * this.x + this.y * this.y);
        },

        Normalize: function()
        {
                var length = this.Length();
                if (length < Number.MIN_VALUE)
                {
                        return 0.0;
                }
                var invLength = 1.0 / length;
                this.x *= invLength;
                this.y *= invLength;

                return length;
        },

        IsValid: function()
        {
                return b2Math.b2IsValid(this.x) && b2Math.b2IsValid(this.y);
        },

        x: null,
        y: null};
b2Vec2.Make = function(x_, y_)
        {
                return new b2Vec2(x_, y_);
        };



  *
  * This software is provided 'as-is', without any express or implied
  * warranty.  In no event will the authors be held liable for any damages
  * arising from the use of this software.
  * Permission is granted to anyone to use this software for any purpose,
  * including commercial applications, and to alter it and redistribute it
  * freely, subject to the following restrictions:
  * 1. The origin of this software must not be misrepresented; you must not
  * claim that you wrote the original software. If you use this software
  * in a product, an acknowledgment in the product documentation would be
  * appreciated but is not required.
  * 2. Altered source versions must be plainly marked, and must not be
  * misrepresented the original software.
  * 3. This notice may not be removed or altered from any source distribution.
  */
  
  // b2Vec2 has no constructor so that it
  // can be placed in a union.
  var b2Vec2 = Class.create();
  b2Vec2.prototype = 
  {
          initialize: function(x_, y_) {this.x=x_; this.y=y_;},
  
          SetZero: function() { this.x = 0.0; this.y = 0.0; },
          Set: function(x_, y_) {this.x=x_; this.y=y_;},
          SetV: function(v) {this.x=v.x; this.y=v.y;},
  
          Negative: function(){ return new b2Vec2(-this.x, -this.y); },
  
          Copy: function(){
                  return new b2Vec2(this.x,this.y);
          },
  
          Add: function(v)
          {
                  this.x += v.x; this.y += v.y;
          },
  
          Subtract: function(v)
          {
                  this.x -= v.x; this.y -= v.y;
          },
  
          Multiply: function(a)
          {
                  this.x *= a; this.y *= a;
          },
  
          MulM: function(A)
          {
                  var tX = this.x;
                  this.x = A.col1.x * tX + A.col2.x * this.y;
                  this.y = A.col1.y * tX + A.col2.y * this.y;
          },
  
          MulTM: function(A)
          {
                  var tX = b2Math.b2Dot(this, A.col1);
                  this.y = b2Math.b2Dot(this, A.col2);
                  this.x = tX;
          },
  
          CrossVF: function(s)
          {
                  var tX = this.x;
                  this.x = s * this.y;
                  this.y = -s * tX;
          },
  
          CrossFV: function(s)
          {
                  var tX = this.x;
                  this.x = -s * this.y;
                  this.y = s * tX;
          },
  
          MinV: function(b)
          {
                  this.x = this.x < b.x ? this.x : b.x;
                  this.y = this.y < b.y ? this.y : b.y;
          },
  
          MaxV: function(b)
          {
                  this.x = this.x > b.x ? this.x : b.x;
                  this.y = this.y > b.y ? this.y : b.y;
          },
  
          Abs: function()
          {
                  this.x = Math.abs(this.x);
                  this.y = Math.abs(this.y);
          },
  
          Length: function()
          {
                  return Math.sqrt(this.x * this.x + this.y * this.y);
          },
  
          Normalize: function()
          {
                  var length = this.Length();
                  if (length < Number.MIN_VALUE)
                  {
                          return 0.0;
                  }
                  var invLength = 1.0 / length;
                  this.x *= invLength;
                  this.y *= invLength;
  
                  return length;
          },
  
          IsValid: function()
          {
                  return b2Math.b2IsValid(this.x) && b2Math.b2IsValid(this.y);
          },
  
          x: null,
          y: null};
  b2Vec2.Make = function(x_, y_)
          {
                  return new b2Vec2(x_, y_);
          };