title: Off-screen enemy indicator algorithm
body: <p>So I'm using Unity to do this, but I'm not sure that matters.</p>
  
  <p>I have enemies that are off the visible screen, and I'd like to have indicators on the side of the screen to denote where they are. That's fine, but there's a lot of enemies so I want to group them into blobs. As in, rather than showing 8 indicators on top of each other, I want 1 indicator with an (8) next to it.</p>
  
  <p>So right now, my algorithm is:</p>
  
  <ul>
  <li>minimum blog range is a constant that I set</li>
  <li>loop through all enemies
  <ul>
  <li>check distance to all enemies already assigned to blobs, if within range, assign to blob</li>
  <li>if not, check other non-assigned enemies, if any are within blob range, make a blob</li>
  </ul></li>
  </ul>
  
  <p>I'm doing this every frame, and it feels inefficient. What can I do to improve this as well as save on processing between frames. As in, what could I do with the previous frame's data to make this better (since the likelihood of the blob's members changing is very low, but it'll definitely have an updated position).</p>
  
  <p>Or, should I just stop worrying about it and continue on, because it's just vector math and it isn't really going to cause problems for the engine.</p>