Hello! I'm trying to simulate a molecular movement. the more heat the greater the movement. For now I got the basics covered. I put approx. 10 particles (sprites) on my canvas, and with physics have them bounce around 4 invisible rectangular sprites forming a box.
What I am looking to achieve is that the particles would be "trapped" inside a circle and have the circle expand and contract to give the particles more space to travel.
Is this something doable. I am assuming it would have something to do with the collision shape, but not sure how.