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                <!-- each object needs a unique ID although this could be removed for the className check -->
<p>This script dynamic draws SVG lines between DOM objects and updates after window resizing. <span class="btn">Randomize points</span></p>
<div id="one" class="point"></div>
<div id="two" class="point"></div>
<div id="three" class="point"></div>
<div id="four" class="point"></div>

<svg id="svg">
  <line id="line" class="line original" stroke-dasharray="5, 5"/>



                html, body{
  margin: 0;
  padding: 0;

    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;



  width: 15px;
  height: 15px;
  background: #d54501;
  position: absolute;
  z-index: 10;  

body {
  font-family: 'Niramit', sans-serif;
  background-color: #b2ada3;

p {
  margin-left: 20px;
  position: relative;
  z-index: 11;
  background: rgba(178, 173, 163, .55)
  top: 80px;
  left: 50px;

  top: 290px;
  right: 50px;
#three {
  top: 390px;
  right: 150px;
#four {
  top: 590px;
  left: 20px;
.btn {
  display: inline-block;
  background: #4e7c80;
  color: white;
  padding: 10px 15px;
  margin-left: 5px;
  cursor: pointer;
  position: relative;
  z-index: 11;
  line-height: 1em;
  &:hover {
    background: darken(#4e7c80, 10%);


                const config = {
  target: $(".point"),
  line: $(".line"),
  delay: 40 // enter zero for live resizing
const drawBetweenObjects = {
  //cmake the line
  makeLine: function(line, div1, div2) {
    var className = div1.attr('id') + div2.attr('id');
    if ( className.includes("undefined") !== true ) { //error check
      //calculations (for legibility, these are separte vars)
      var x1 = div1.offset().left + (div1.width()/2);
      var y1 = div1.offset().top + (div1.height()/2);
      var x2 = div2.offset().left + (div2.width()/2);
      var y2 = div2.offset().top + (div2.height()/2);
      $("."+className).attr('x1',x1).attr('y1',y1).attr('x2',x2).attr('y2',y2); //svg attributes
    } else { console.error("undefined object") }
  findLines: function(search) {
   $(".deleteMe").remove(); //remove last set of lines
    $(search).each(function(index, el){
      if ( search.eq(index + 1).length ) { //only do drawBetweenObject if there is another.
        drawBetweenObjects.makeLine(config.line, $(this), search.eq(index + 1));   //args order - line, div1 and div2 - the next div.
  init: function() {
    drawBetweenObjects.findLines( );
    //give resizing time to happen
    var resizeId;
    $(window).resize(function() {
        if (config.delay !== 0) {
          resizeId = setTimeout(doneResizing, config.delay);
        } else {
          drawBetweenObjects.findLines( );
    function doneResizing(){
      drawBetweenObjects.findLines( );


// umimportant ugly scripting
// this just randomizes the points
// It's pretty ugly.
$(".btn").click(function() {
  var heightMax = $(document).height(),
      widthMax = $(document).width();
  function widthCalc () {
    return Math.floor( Math.random() * widthMax );
  function heightCalc() {
    return Math.floor( Math.random() * heightMax )
  $("#one").css({  left: widthCalc(),  top: heightCalc() });
  $("#four").css({ left: widthCalc(),  top: heightCalc() });
  $("#three").css({ right: widthCalc(), top: heightCalc() });
  $("#two").css({ right: widthCalc(), top: heightCalc()  });
   drawBetweenObjects.findLines( );