A vertex record in an envelope diagram. It is always associated with a point on the lower (upper) envelope of a nonempty set of curves. A vertex is also associated with a set of $$xmonotone curves that induce the envelope over this point. It is incident to two edges, one lying to its left and the other to its right.
 
default constructor.
 
 
copy constructor.
 
 
constructs a vertex associated with the given point p.


 returns the point associated with v. 

 returns the number of $$xmonotone curves associated with v. 

 return an iterator for the first $$xmonotone curve associated with v. 

 return a pasttheend iterator for the $$xmonotone curves associated with v. 

 returns the edge lying to v's left. 

 returns the edge lying to v's right. 

 associates the point p with v. 

 clears the set of curves associated with v. 

 
adds the $$xmonotone curve cv to the set of curves associated with v.  

 
adds the given range of $$xmonotone curves to the set of curves associated with v.  

 sets the edge lying to the left of v to be e. 

 
sets the edge lying to the right of v to be e. 