title: simple shape recognition
body: <p>I wanna achieve something that looks like the <a href="http://www.youtube.com/watch?v=orEUACY3OHg" rel="nofollow">wizard's ability in the game Trine</a>.</p>
  
  <p>I want to create a game where the player uses the mouse to create certain objects, so i will need to compare the shape the player drew to a predefined shape of my own and check if its close.</p>
  
  <p>I have no idea how to achieve this and where to look for, I assume it has something to do with shape recognition like in image processing and computer vision but it should be much simpler and work in real time.</p>
  
  <p>does anyone have a clue how this can be done or where can i look for something like that?</p>