How to find out if a point belongs to a specified segment?

Question

API

I have a certain base of segments (steps) of the route:

I have the coordinates of a point that exactly belongs to one of the specified routes. How do I know which route leg a point belongs to?

Answer 1

So get the equation of a straight line through 2 points.
Make sure that x0<= x <= x1 and y0 <= y <= y1 (x0 < x1, same as y0 < y1)
Insert a point into a line.
Check for equality.
Season with errors.