とりあえずベクトルを

とりあえずベクトル計算を行いたかったので、こんなプログラムを作ってみた。３次元ベクトルの足算、引算、内積、外積、正規化を行える...はず

var Vector3 = function(){
    this.elements = new Array(0.0, 0.0, 0.0);
    
    this.set = function(x, y, z){
        this.elements[0] = x;
        this.elements[1] = y;
        this.elements[2] = z;
        
        return this;
    }
    
    this.seta = function(other){
        for(var i = 0; i < 3; i++){
            this.elements[i] = other[i];
        }
        
        return this;
    }
    
    this.setv = function(other){
        for(var i = 0; i < 3; i++){
            this.elements[i] = other.elements[i];
        }
        
        return this;
    }
    
    this.add = function(other){
        for(var i = 0; i < 3; i++){
            this.elements[i] += other.elements[i];
        }
        
        return this;
    }
    
    this.sub = function(other){
        for(var i = 0; i < 3; i++){
            this.elements[i] -= other.elements[i];
        }
        
        return this;
    }
    
    this.length = function(){
        var ret = 0.0;
        
        for(var i = 0; i < 3; i++){
            ret += this.elements[i] * this.elements[i];
        }
        
        return Math.sqrt(ret);
    }
    
    this.normalize = function(){
       var length = this.length();
       
       for(var i = 0; i < 3; i++){
           this.elements[i] /= length;
       }
       
       return this;
    }
    
    this.dot = function(other){
        var ret = 0.0;
        
        for(var i = 0; i < 3; i++){
            ret += this.elements[i] * other.elements[i];
        }
        
        return ret;
    }
    
    this.cross = function(other){
        return new Vector3().set(
            this.elements[1] * other.elements[2] - this.elements[2] * other.elements[1],
            this.elements[2] * other.elements[0] - this.elements[0] * other.elements[2],
            this.elements[0] * other.elements[1] - this.elements[1] * other.elements[0]
        );
    }
}

Vector3.add = function(v1, v2){
    return new Vector3().setv(v1).add(v2);
}

Vector3.sub = function(v1, v2){
    return new Vector3().setv(v1).sub(v2);
}

Vector3.dot = function(v1, v2){
    return v1.dot(v2);
}

Vector3.cross = function(v1, v2){
    return v1.cross(v2);
}