c++: CGAL 2D delauny triangulation: Concave Shapes -

I am currently meeting CGAL for some 2D triode tasks and I find something simple to do anything has gone. Either way I actually get to actually triangulate the gap size from now on, I always get the convex hull of all the points. Actually I want to add points on the mouseclick as it works in the drawing, so that all of them in order Point shape should be outlined. How can I do this with CGAL? In general, a simple example of making concave shapes triangular will take me on the right path! Thanks!