title: How do you calculate the radius of the smallest circle-shape that a sprite would fit in?
body: <p>I am making a game in HTML5, JS.</p>
  
  <p>In the game I perform the collisions by circle-shapes since my sprites are rotating.</p>
  
  <p>The player has different shapes since it has different sprites when it holds different weapons.</p>
  
  <p>The radius of the player is half the sprites width / height.</p>
  
  <p>The sprites are resized from 16x16 to 50x50 pixels (50 / 16 = 3.125, so 3.125 times bigger)</p>
  
  <p><strong>My question is: How do you calculate the radius of the smallest circle-shape that the sprite would fit in? Like this:</strong></p>
  
  <p>Normal Sprite: <a href="http://imgur.com/wWS1nDy" rel="nofollow">http://imgur.com/wWS1nDy</a></p>
  
  <p>Red = To calculate radius of (how?), Blue = Radius I use (sprite width or height / 2): <a href="http://imgur.com/kytpRPz" rel="nofollow">http://imgur.com/kytpRPz</a></p>
  
  <p>(For a better look of the images open them in a image program or something to zoom in please.)</p>