https://threejs.org/examples/?q=draw#webgl_buffergeometry_drawrange
I want it to be round instead of a square but I couldn’t.
Hi!
Set vertices inside of a sphere. When a point is further, than the set radius, reflect its velocity vector via a normal, which is simply normalized and negated position of the point (I used .reflect() method of Vector3)
Thus, you’ll get something like this:
Thank you so much! 
