title: Is there a robust C++ implementation of the Bentley-Ottmann algorithm?
body: <p>The Bentley-Ottoman algorithm finds all crossings in a set of line segments. For a well known and important algorithm, it seems quite weird that a C++ implementation of Bentley-Ottmann algorithm &mdash; the implementation that can handle all the degenerated cases (i.e., no special assumption on the sweeping line and the number of intersection points, and so on) &mdash; is simply not available. The only code I can found is <a href="http://www.koders.com/c/fid78DC582FD108792293256F28AB5B27F7120E62FF.aspx?s=skiplist#L39" rel="nofollow noreferrer">here</a>, but it doesn't seem to handle <a href="https://stackoverflow.com/q/4213117/3834">the generalized case</a>.</p>
  
  <p>Is Bentley-Ottmann algorithm <em>already</em> implemented in any well-tested library, such as Boost or LEDA? If yes, may I have the reference to it?</p>