equals = (line1, line2) => {
  // compare directions (unit vectors)
  if (!vec3.equals(line1[1], line2[1])) return false

  // compare points
  if (!vec3.equals(line1[0], line2[0])) return false

  // why would lines with the same slope (direction) and different points be equal?
  // let distance = distanceToPoint(line1, line2[0])
  // if (distance > EPS) return false

  return true
}
Compare the given lines for equality.

@param {line3} line1 - first line to compare
@param {line3} line2 - second line to compare
@return {Boolean} true if lines are equal
@alias module:modeling/maths/line3.equals