JSFiddle - React, Tailwind, and code Playground

JavaScript

var paper = Raphael(0, 0, '100%', '100%');

var path1 = paper.path("M0 0L100 100");
var path2 = paper.path("M100 0L0 100");

var array1 = new Array();
var array2 = new Array();

for(var i = 0; i < path1.getTotalLength(); i++) {
    array1.push(path1.getPointAtLength(i));
}

for(var i = 0; i < path2.getTotalLength(); i++) {
    array2.push(path2.getPointAtLength(i));
}

for(var i = 0; i < array1.length; i++) {
    for(var k = 0; k < array2.length; k++) {
        // the threshold +-1 is important!
        if(array1[i].x < ( array2[k].x + 1 ) &&
           array1[i].x > ( array2[k].x - 1 )){
            if(array1[i].y < ( array2[k].y + 1 ) &&
               array1[i].y > ( array2[k].y - 1 )){
                // alert('yeah'); // uncomment this. It will alert 4 times.
            } 
        }  
    }
}