CGAL 5.5.2 - 2D Arrangements
ArrTraits::CompareXOnBoundary_2 Concept Reference

## Operations

A model of this concept must provide:

Comparison_result operator() (const ArrTraits::Point_2 &p1, const ArrTraits::Point_2 &p2)
Given two points p1 and p2, such that either p1 or p2 (or both) lie on the bottom or top boundary of the parameter space, compares the $$x$$-coordinate of p1 and the $$x$$-coordinate of p2. More...

## ◆ operator()()

 Comparison_result ArrTraits::CompareXOnBoundary_2::operator() ( const ArrTraits::Point_2 & p1, const ArrTraits::Point_2 & p2 )

Given two points p1 and p2, such that either p1 or p2 (or both) lie on the bottom or top boundary of the parameter space, compares the $$x$$-coordinate of p1 and the $$x$$-coordinate of p2.

Returns CGAL::SMALLER, CGAL::EQUAL, or CGAL::LARGER accordingly.

Precondition
Parameter_space_in_y_2 (p1) $$\neq$$ CGAL::ARR_INTERIOR or Parameter_space_in_y_2 (p2) $$\neq$$ CGAL::ARR_INTERIOR.