/* Line Intersect boolean function by Paul Caron 2020 struct Point2d: -move constructor -parameter constructor -x,y coordinates struct Segment: -parameters constructor with rvalue Points -point A and point B (begin and end of line segment) -m the slope (calculated upon Segment construction) -c the constant at x=0;((y=mx+c) also calculated upon construction) segments_intersect(Segment s1,Segment s2): -returns true if segment lines intersect each other, otherwise returns false */ #include #include #include using namespace std; struct Point2d{ const double x,y; Point2d(double x,double y):x(x),y(y){} Point2d(Point2d&&p):x(move(p.x)),y(move(p.y)){} }; struct Segment{ const Point2d A,B; const double m,c; Segment(Point2d&& a,Point2d&& b): A(forward(a.x(a.xs2.B.x) return false; const double y=s2.m*x+s2.c; if(ymax(s1.A.y,s1.B.y)) return false; return true; } if(s2.m==INFINITY){ const double x=s2.A.x; if(xs1.B.x) return false; const double y=s1.m*x+s1.c; if(ymax(s2.A.y,s2.B.y)) return false; return true; } const double x=(s2.c-s1.c)/(s1.m-s2.m); if(xs1.B.x||x>s2.B.x) return false; const double y=s1.m*x+s1.c; if(ymax({s1.A.y,s1.B.y,s2.A.y,s2.B.y})) return false; return true; } int main() { Segment s1{{1,2},{3,4}}; Segment s2{{2,0},{2,-4}}; Segment s3{{-5,5},{5,5}}; Segment s4{{-4,3},{4,4}}; Segment s5{{-4,3},{3,0}}; Segment s6{{-4,-2},{3,1}}; Segment s7{{-4,5},{4,4}}; Segment s8{{0,5},{4,5}}; Segment s9{{0,0},{5,5}}; cout << segments_intersect(s1,s2)<

bool line segments intersect