freesewing/markdown/dev/tutorials/pattern-design/part2/completing-the-neck-opening/en.md

title	order
Completing the neck opening	80

We've constructed the perfectly sized quarter neck, and we're going to use this to create our complete neck path by flipping and mirroring it.

Hiding our quarter neck opening

To make our code easier to understand, we're going to leave the quarterNeck path as it is, and simply chose to not show it.

To accomplish this, we'll call the hide() method on our path:

```design/src/bib.mjs function draftBib({ Path, Point, paths, points, measurements, options, part, }) {

/*

• Construct the quarter neck opening */ const target = (measurements.head * options.neckRatio) /4 let tweak = 1 let delta do { points.right = new Point( tweak * measurements.head / 10, 0 ) points.bottom = new Point( 0, tweak * measurements.head / 12 )

points.rightCp1 = points.right.shift(
  90, 
  points.bottom.dy(points.right) / 2
)
points.bottomCp2 = points.bottom.shift(
  0, 
  points.bottom.dx(points.right) / 2
)

paths.quarterNeck = new Path()
  .move(points.right)
  .curve(
    points.rightCp1, 
    points.bottomCp2, 
    points.bottom
  )
  // highlight-start
  .hide()
  // highlight-end

delta = paths.quarterNeck.length() - target
if (delta > 0) tweak = tweak * 0.99
else tweak = tweak * 1.02

} while (Math.abs(delta) > 1)

return part }

</Example>

We're saying: _hide this path_. In other words, don't show it.
The path is still known, and we can still use it to calculate the length of the neck opening.
But it won't show up on screen or on the page.

## Create the complete neck opening

Now that we've hidden our homework, let's create the complete neck path.
As the neck opening is symmetrical, there's no need to re-calculate the points
on the other side. We can just flip them over, so to speak. And that's exactly
what we'll do.

Let's add some more points, and then construct the complete path for the neck
opening.

<Example tutorial caption="Our completed neck opening">
```design/src/bib.mjs
function draftBib({
  Path,
  Point,
  paths,
  points,
  measurements,
  options,
  part,
}) {

  /*
   * Construct the quarter neck opening
   */
  const target = (measurements.head * options.neckRatio) /4
  let tweak = 1
  let delta
  do {
    points.right = new Point(tweak * measurements.head / 10, 0)
    points.bottom = new Point(0, tweak * measurements.head / 12)
    points.rightCp1 = points.right.shift( 90, points.bottom.dy(points.right) / 2)
    points.bottomCp2 = points.bottom.shift( 0, points.bottom.dx(points.right) / 2)

    paths.quarterNeck = new Path()
      .move(points.right)
      .curve(points.rightCp1, points.bottomCp2, points.bottom)
      .hide()

    delta = paths.quarterNeck.length() - target
    if (delta > 0) tweak = tweak * 0.99
    else tweak = tweak * 1.02
  } while (Math.abs(delta) > 1)

  // highlight-start
  /*
   * Construct the complete neck opening
   */
  points.rightCp2 = points.rightCp1.flipY()
  points.bottomCp1 = points.bottomCp2.flipX()
  points.left = points.right.flipX()
  points.leftCp1 = points.rightCp2.flipX()
  points.leftCp2 = points.rightCp1.flipX()
  points.top = points.bottom.flipY()
  points.topCp1 = points.bottomCp2.flipY()
  points.topCp2 = points.bottomCp1.flipY()

  paths.neck = new Path()
    .move(points.top)
    .curve(points.topCp2, points.leftCp1, points.left)
    .curve(points.leftCp2, points.bottomCp1, points.bottom)
    .curve(points.bottomCp2, points.rightCp1, points.right)
    .curve(points.rightCp2, points.topCp1, points.top)
    .close()
    .addClass('fabric')
  // highlight-end

  return part
}

To add the points, we're using the Point.flipX() and Point.flipY() methods here. There's a few new Path methods too, like close() and addClass().

Perhaps you can figure out what they do? If not, both the Point documentation and the Path documentation have detailed info on all the methods available, including these.