public static void main(String[] args){ //declaring coordinates int x1 = 50; int y1 = 100; int x2 = 250; int y2 = 150; //drawing line Graphics2D.lineStyle(3); Graphics2D.moveTo(x1, y1); graphics.lineTo(x2, y2) //forming line vectors line = new Vector2D(x2 - x1, y2 - y1); leftNormal = line.rotate(Math.PI * -0.5); }