How to draw a convexthull and a polygon around the hand in this tutorial.

I found this tutorial in JavaCV how to detect a hand gesture. But it doesn't show how to draw the convexhull or a polygon around the palm. Can someone tell me how to do that in this example?

http://www.javacodegeeks.com/2012/12/hand-and-finger-detection-using-javacv.html

Just draw it on the Graphics2D in draw()?

That example has all the code and extensive explanations. What exactly do you need that's not in the code or the explanations?

QThat example has all the code and extensive explanations. What exactly do you need that's not in the code or the explanations?

It doesn't show how to Draw a Convexhull. It shows how to calculae it but there is no demonstration on how to draw it on the image.

Just draw it on the Graphics2D in draw()?

That is what I want to know how

there is no method in Graphics2d to draw a Convexhull. It is a JavaCV thing

Correct. AFAIK, You'll need to get the geometry of it and draw it onto the Graphics2D.