intersection-point

readme.md

intersection-point

Created with <3 with dartpad.dev.

main.dart

void main() {
  final p1 = Point(0, 0);
  final p2 = Point(-5, -10);
  final p3 = Point(-10, -5);
  final p4 = Point(15, -5);
  final r1 = Line(p1, p2);
  final r2 = Line(p3, p4);
  final pi = intersection(r1, r2);
  print("${pi.x}, ${pi.y}");
}

class Point {
  const Point(this.x, this.y); 

  final double x;
  final double y;
}

class Line {
  const Line(this.one, this.two);

  final Point one;
  final Point two;

  double get m => (two.y - one.y) / (two.x - one.x);
}

Point intersection(Line r1, Line r2) {
  final x = (-1 * r1.m * r1.one.x + r2.m * r2.one.x + r1.one.y - r2.one.y) / (r2.m - r1.m);
  final y = r1.m * (x - r1.one.x) + r1.one.y;
  return Point(x, y);
}