Can we do this for 1M avatars as circles? I want it to start from initial 100 circles and expand slowly as new users are added exponentially (every user from the initial 100 has to invite 2 other new users, and it keeps going). The avatars need to be clickable for poping up more info and zoom needs to be controlled manually, but this random jump/animation is fun by default, we can stop it as soon as the user clicks/touches the screen.

I would not recommend using SVG for more than 10k elements. For a million elements you might want to work directly in WebGL. You can still use D3's zoom functions of course to control the interaction, but rendering is going to be a challenge.

Thank you for your reply, any example? Thanks.