hw3

// navigare nei prototipi costa! per evitare l'accesso alla stessa proprietà assgno propr = Math.propr;
var pow = Math.pow;
var sqrt = Math.sqrt;

/* POINT */
var Point = function(x,y){
  this.x = x || 0;
	this.y = y || 0;
}

Point.prototype.getDistance = function(point) {
	var XDistance = this.x - point.x;
	var YDistance = this.y - point.y;
	
	return sqrt(pow(XDistance,2)+pow(YDistance,2));
};

Point.prototype.translate = function(dx,dy) {
	this.x += dx;
	this.y += dy;

	return this;
};

/* TRIANGLE */
var Triangle = function (p1,p2,p3){
	this.p1 = p1;
	this.p2 = p2;
	this.p3 = p3;

	this.l1 = p1.getDistance(p2);
	this.l2 = p1.getDistance(p3);
	this.l3 = p1.getDistance(p3);
}

Triangle.prototype.getPerimeter = function() {
	var perimeter = this.l1+this.l2+this.l3;
	
	return perimeter;
};

Triangle.prototype.getArea = function() {
	var semiperimeter = this.getPerimeter() / 2;
	return sqrt(semiperimeter*(semiperimeter - this.l1)*(semiperimeter - this.l2)*(semiperimeter - this.l3));
};

var p1 = new Point(0,0);

p1.translate(1,2);