How I handle action on the interface

If some are curious, there's a post here about the technique I'm using to handle events on the interface (characters and NPCs movements, attacks and such). Now the real question is how much the browser will be able to deal with before everything becomes too laggy.

So far I've only tested with 1 character and 4 NPCs at the same time and I had no problem at all. I'm guessing that if there was 50 avatars on the screen at the same time things would be a bit different but if that's ever the case, I guess that'd be a "happy problem".

I won't wait long before testing this since it might have an impact on how movements/events are dealt with.