// ********************************************************** // File: Segment.cpp // Description: Implementation of class Segment // // Author: Carlos Moreno // ********************************************************** #include "Segment.h" #include "Triangle.h" // orientation function #include "graphic_interface.h" bool Segment::intersects (const Segment & s) const { return turn (p1, p2, s.p1) == -turn (p1, p2, s.p2) && turn (s.p1, s.p2, p1) == -turn (s.p1, s.p2, p2); } bool Segment::contains (const Point & p) const { return turn (p1, p2, p) == collinear && ((p-p1) * (p-p2) < 0); // If the scalar product is negative, it means // p1-p and p2-p are in opposite senses; therefore, // p is between p1 and p2 } void Segment::draw () const { draw_line (p1.get_x(), p1.get_y(), p2.get_x(), p2.get_y()); } bool Segment::operator== (const Segment & s) const { return p1 == s.p1 && p2 == s.p2; } bool Segment::operator!= (const Segment & s) const { return !(*this == s); }