title: How to determine if an (x, y) point is within a polygon defined by a list of boundary points
body: <p>I have a big list of points that define a boundary of some (not necessarily convex) shape.  I then have some query point <code>(x, y)</code> and I want to determine whether <code>(x, y)</code> is within the region defined by my boundary of points.</p>
  
  <p>So, simple enough question.  How do I determine whether the query point would be inside the shape formed by my boundary points?  And is there a nice boost module for this?  I am looking through <code>boost::geometry</code> but haven't found anything yet..</p>