How to massively over-engineer a method which is possible natively with getBoundingClientRect() - A guide by someone who didn't know about getBoundingClientRect()

over-engineered.js

calculateWidthOld: function (elem) {
  var tr, values, transform,
      a, b,
      angle, width, height,
      adjustedWidth;

  transform = [
    elem.css('-webkit-transform'),
    elem.css('-moz-transform'),
    elem.css('-ms-transform'),
    elem.css('-o-transform'),
    elem.css('transform')
  ];

  // Take the first value that isn't undefined from our array
  tr = transform[0] || transform[1] || transform[2] || transform[3];

  values = tr.split('(')[1];
  values = values.split(')')[0];
  values = values.split(',');

  a = values[0];
  b = values[1];

  angle  = Math.atan2(b, a); // Angle in radians
  if (angle < 0) { angle = angle * -1; } // Make sure our angle is positive

  width  = elem.width();
  height = elem.height();

  // http://stackoverflow.com/questions/9791403/how-to-get-actual-not-original-height-of-a-css-rotated-element
  adjustedWidth = (height * Math.sin(angle)) + (width * Math.cos(angle));

  return adjustedWidth;
}