public function @ax-lib-flex-animation-code-02-com-foed-Vector2D(x:Number = 0, y:Number = 0)
                {
                        _x = x;
                        _y = y;
                }
                
                

* Can be used to visualize the vector. Generally used for debug purposes only. *
parameter: graphics The Graphics instance to draw the vector on. * @param color The color of the line used to represent the vector. */ public function draw(graphics:Graphics, color:uint = 0):void { graphics.lineStyle(0, color); graphics.moveTo(0, 0); graphics.lineTo(_x, _y); } /** * Generates a copy of this vector. * @return @ax-lib-flex-animation-code-02-com-foed-Vector2D A copy of this vector. */ public function clone():@ax-lib-flex-animation-code-02-com-foed-Vector2D { return new @ax-lib-flex-animation-code-02-com-foed-Vector2D(x, y); } /** * Sets this vector's x and y values, and thus length, to zero. * @return @ax-lib-flex-animation-code-02-com-foed-Vector2D A reference to this vector. */ public function zero():@ax-lib-flex-animation-code-02-com-foed-Vector2D { _x = 0; _y = 0; return this; } /** * Whether or not this vector is equal to zero, i.e. its x, y, and length are zero. * @return Boolean True if vector is zero, otherwise false. */ public function isZero():Boolean { return _x == 0 && _y == 0; } /** * Sets / gets the length or magnitude of this vector. Changing the length will change the x and y but not the angle of this vector. */ public function set length(value:Number):void { var a:Number = angle; _x = Math.cos(a) * value; _y = Math.sin(a) * value; } public function get length():Number { return Math.sqrt(lengthSQ); } /** * Gets the length of this vector, squared. */ public function get lengthSQ():Number { return _x * _x + _y * _y; } /** * Gets / sets the angle of this vector. Changing the angle changes the x and y but retains the same length. */ public function set angle(value:Number):void { var len:Number = length; _x = Math.cos(value) * len; _y = Math.sin(value) * len; } public function get angle():Number { return Math.atan2(_y, _x); } /** * Normalizes this vector. Equivalent to setting the length to one, but more efficient. * @return @ax-lib-flex-animation-code-02-com-foed-Vector2D A reference to this vector. */ public function normalize():@ax-lib-flex-animation-code-02-com-foed-Vector2D { if(length == 0) { _x = 1; return this; } var len:Number = length; _x /= len; _y /= len; return this; } /** * Ensures the length of the vector is no longer than the given value. * @param max The maximum value this vector should be. If length is larger than max, it will be truncated to this value. * @return @ax-lib-flex-animation-code-02-com-foed-Vector2D A reference to this vector. */ public function truncate(max:Number):@ax-lib-flex-animation-code-02-com-foed-Vector2D { length = Math.min(max, length); return this; } /** * Reverses the direction of this vector. * @return @ax-lib-flex-animation-code-02-com-foed-Vector2D A reference to this vector. */ public function reverse():@ax-lib-flex-animation-code-02-com-foed-Vector2D { _x = -_x; _y = -_y; return this; } /** * Whether or not this vector is normalized, i.e. its length is equal to one. * @return Boolean True if length is one, otherwise false. */ public function isNormalized():Boolean { return length == 1.0; } /** * Calculates the dot product of this vector and another given vector. * @param v2 Another @ax-lib-flex-animation-code-02-com-foed-Vector2D instance. * @return Number The dot product of this vector and the one passed in as a parameter. */ public function dotProd(v2:@ax-lib-flex-animation-code-02-com-foed-Vector2D):Number { return _x * v2.x + _y * v2.y; } /** * Calculates the cross product of this vector and another given vector. * @param v2 Another @ax-lib-flex-animation-code-02-com-foed-Vector2D instance. * @return Number The cross product of this vector and the one passed in as a parameter. */ public function crossProd(v2:@ax-lib-flex-animation-code-02-com-foed-Vector2D):Number { return _x * v2.y - _y * v2.x; } /** * Calculates the angle between two vectors. * @param v1 The first @ax-lib-flex-animation-code-02-com-foed-Vector2D instance. * @param v2 The second @ax-lib-flex-animation-code-02-com-foed-Vector2D instance. * @return Number the angle between the two given vectors. */ public static function angleBetween(v1:@ax-lib-flex-animation-code-02-com-foed-Vector2D, v2:@ax-lib-flex-animation-code-02-com-foed-Vector2D):Number { if(!v1.isNormalized()) v1 = v1.clone().normalize(); if(!v2.isNormalized()) v2 = v2.clone().normalize(); return Math.acos(v1.dotProd(v2)); } /** * Determines if a given vector is to the right or left of this vector. * @return int If to the left, returns -1. If to the right, +1. */ public function sign(v2:@ax-lib-flex-animation-code-02-com-foed-Vector2D):int { return perp.dotProd(v2) < 0 ? -1 : 1; } /** * Finds a vector that is perpendicular to this vector. * @return @ax-lib-flex-animation-code-02-com-foed-Vector2D A vector that is perpendicular to this vector. */ public function get perp():@ax-lib-flex-animation-code-02-com-foed-Vector2D { return new @ax-lib-flex-animation-code-02-com-foed-Vector2D(-y, x); } /** * Calculates the distance from this vector to another given vector. * @param v2 A @ax-lib-flex-animation-code-02-com-foed-Vector2D instance. * @return Number The distance from this vector to the vector passed as a parameter. */ public function dist(v2:@ax-lib-flex-animation-code-02-com-foed-Vector2D):Number { return Math.sqrt(distSQ(v2)); } /** * Calculates the distance squared from this vector to another given vector. * @param v2 A @ax-lib-flex-animation-code-02-com-foed-Vector2D instance. * @return Number The distance squared from this vector to the vector passed as a parameter. */ public function distSQ(v2:@ax-lib-flex-animation-code-02-com-foed-Vector2D):Number { var dx:Number = v2.x - x; var dy:Number = v2.y - y; return dx * dx + dy * dy; } /** * Adds a vector to this vector, creating a new @ax-lib-flex-animation-code-02-com-foed-Vector2D instance to hold the result. * @param v2 A @ax-lib-flex-animation-code-02-com-foed-Vector2D instance. * @return @ax-lib-flex-animation-code-02-com-foed-Vector2D A new vector containing the results of the addition. */ public function add(v2:@ax-lib-flex-animation-code-02-com-foed-Vector2D):@ax-lib-flex-animation-code-02-com-foed-Vector2D { return new @ax-lib-flex-animation-code-02-com-foed-Vector2D(_x + v2.x, _y + v2.y); } /** * Subtacts a vector to this vector, creating a new @ax-lib-flex-animation-code-02-com-foed-Vector2D instance to hold the result. * @param v2 A @ax-lib-flex-animation-code-02-com-foed-Vector2D instance. * @return @ax-lib-flex-animation-code-02-com-foed-Vector2D A new vector containing the results of the subtraction. */ public function subtract(v2:@ax-lib-flex-animation-code-02-com-foed-Vector2D):@ax-lib-flex-animation-code-02-com-foed-Vector2D { return new @ax-lib-flex-animation-code-02-com-foed-Vector2D(_x - v2.x, _y - v2.y); } /** * Multiplies this vector by a value, creating a new @ax-lib-flex-animation-code-02-com-foed-Vector2D instance to hold the result. * @param v2 A @ax-lib-flex-animation-code-02-com-foed-Vector2D instance. * @return @ax-lib-flex-animation-code-02-com-foed-Vector2D A new vector containing the results of the multiplication. */ public function multiply(value:Number):@ax-lib-flex-animation-code-02-com-foed-Vector2D { return new @ax-lib-flex-animation-code-02-com-foed-Vector2D(_x * value, _y * value); } /** * Divides this vector by a value, creating a new @ax-lib-flex-animation-code-02-com-foed-Vector2D instance to hold the result. * @param v2 A @ax-lib-flex-animation-code-02-com-foed-Vector2D instance. * @return @ax-lib-flex-animation-code-02-com-foed-Vector2D A new vector containing the results of the division. */ public function divide(value:Number):@ax-lib-flex-animation-code-02-com-foed-Vector2D { return new @ax-lib-flex-animation-code-02-com-foed-Vector2D(_x / value, _y / value); } /** * Indicates whether this vector and another @ax-lib-flex-animation-code-02-com-foed-Vector2D instance are equal in value. * @param v2 A @ax-lib-flex-animation-code-02-com-foed-Vector2D instance. * @return Boolean True if the other vector is equal to this one, false if not. */ public function equals(v2:@ax-lib-flex-animation-code-02-com-foed-Vector2D):Boolean { return _x == v2.x && _y == v2.y; } /** * Sets / gets the x value of this vector. */ public function set x(value:Number):void { _x = value; } public function get x():Number { return _x; } /** * Sets / gets the y value of this vector. */ public function set y(value:Number):void { _y = value; } public function get y():Number { return _y; } /** * Generates a string representation of this vector. * @return String A description of this vector. */ public function toString():String { return "[@ax-lib-flex-animation-code-02-com-foed-Vector2D (x:" + _x + ", y:" + _y + ")]"; } }}

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[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _

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(C) Æliens 18/6/2009

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