title: A list of vector2 arrays
body: <p>I'm making a 2D game in XNA, and the NPC sprites are all grouping together into one mass, appearing to be one sprite. I thought that a way around this would be to do collision detection on all of the sprites, and just move them away from each other, but that meant doing hundreds of checks a frame.</p>
  
  <p>I then decided to break up the game window into a <code>grid (6*6)</code>, and put each sprite into one of 36 arrays, so I'd only have to check each sprite against each other sprite in the same quadrant. This is now my problem, as I'm checking the position, which is a <code>Vector2</code>, and I have no idea how to put them all in the relevant grid square. </p>
  
  <p>If I've been unclear anywhere, please let me know, and I'll do my best to improve it.</p>