Draggable Column Chart fixing Datapoint to the nearest interval | CanvasJS - JavaScript Charts

Draggable Column Chart fixing Datapoint to the nearest interval | CanvasJS - JavaScript Charts

by canvasjs

HTML

<script src="https://canvasjs.com/assets/script/canvasjs.min.js"></script>
<script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>
    
<div id="chartContainer" style="height: 370px; width: 100%;"></div>

JavaScript

window.onload = function() {

  var chart = new CanvasJS.Chart("chartContainer", {       
    animationEnabled: true,
    title: {
      text: "Try Dragging Any Column to Resize"
    },
    axisX:{
      minimum: 5,
      maximum: 95
    },
    data: [{
      type: "column",
      dataPoints: [
        { x: 10, y: 71 },
        { x: 20, y: 55 },
        { x: 30, y: 50 },
        { x: 40, y: 65 },
        { x: 50, y: 95 },
        { x: 60, y: 68 },
        { x: 70, y: 28 },
        { x: 80, y: 34 },
        { x: 90, y: 14 }
      ]
    }]
  });
  chart.render();

  var xSnapDistance = chart.axisX[0].convertPixelToValue(chart.get("dataPointWidth")) / 2;
  var ySnapDistance = 3;

  var xValue, yValue;

  var mouseDown = false;
  var selected = null;
  var changeCursor = false;

  var timerId = null;
  var yAxisIntervals = [];

  function getNearestValue(currrentY, yAxisIntervals) {
    var nearestYValue = yAxisIntervals[0];
    var diff = Math.abs (currrentY - nearestYValue);
    for (var i = 0; i < yAxisIntervals.length; i++) {
      if (Math.abs (currrentY - yAxisIntervals[i]) < diff) {
        diff = Math.abs (currrentY - yAxisIntervals[i]);
        nearestYValue = yAxisIntervals[i];
      }
    }
    return nearestYValue;
  }


  function getPosition(e) {
    var parentOffset = $("#chartContainer > .canvasjs-chart-container").offset();          	
    var relX = e.pageX - parentOffset.left;
    var relY = e.pageY - parentOffset.top;
    xValue = Math.round(chart.axisX[0].convertPixelToValue(relX));
    yValue = Math.round(chart.axisY[0].convertPixelToValue(relY));
  }

  function searchDataPoint() {
    var dps = chart.data[0].dataPoints;
    for(var i = 0; i < dps.length; i++ ) {
      if( (xValue >= dps[i].x - xSnapDistance && xValue <= dps[i].x + xSnapDistance) && (yValue >= dps[i].y - ySnapDistance && yValue <= dps[i].y + ySnapDistance) ) 
      {
        if(mouseDown) {
          selected = i;
          break;
        } else {
          changeCursor = true;
...