//Constructor
var JPoint=function(x,y)
{
	// Field
	this.x=x;
	this.y=y;
	this.height=0;
	
	// Method
	this.distance=JPoint_distance;
	this.angle=JPoint_angle;
}

function JPoint_distance(x1,y1,x2,y2)
{ 	
	return Math.sqrt((x2-x1)*(x2-x1)+(y2-y1)*(y2-y1)); 	
}

function JPoint_angle(x1,y1,x2,y2)
{
	var an;

	an=Math.atan2(y2-y1,x2-x1);
	
	if(an>0)
		return an;
	else
		return (Math.PI*2+an);
}