freesewing/markdown/dev/tutorials/pattern-design/part2/creating-the-closure/en.md

title	order
Creating the closure	91

Things are starting to look good, but we can't fit the bib over the baby's head like this. So we must create a closure. We'll let the straps overlap at the end, and put in a snap later.

Using macros

To round the straps, we'll use something new: a macro. To use macros, we need the macro method, which we can destructure to get access to it.

Macros are little helpers that automate things that would otherwise get rather tedious. There are macros to add titles to our pattern, or grainline indicators, a scalebox, and there's a macro to round corners. The round macro.

You can find more information on the round macro in the macros docs.

We need a half circle here, but the round macro works on 90° angles, so we'll use it twice. As such, we'll add some points to guide the macro, and then put it to work.

Like our neck opening, we've only drawn half since we can simply copy the points to the other side.

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

/*

• Construct the quarter neck opening */ let tweak = 1 let target = (measurements.head * options.neckRatio) /4 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)

/*

• 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')

/*

• Drawing the bib outline */ const width = measurements.head * options.widthRatio const length = measurements.head * options.lengthRatio

points.topLeft = new Point( width / -2, points.top.y - (width / 2 - points.right.x) ) points.topRight = points.topLeft.shift(0, width) points.bottomLeft = points.topLeft.shift(-90, length) points.bottomRight = points.topRight.shift(-90, length)

paths.rect = new Path() .move(points.topLeft) .line(points.bottomLeft) .line(points.bottomRight) .line(points.topRight) .line(points.topLeft) .close() .addClass('fabric')

/*

• Shape the straps */ points.edgeLeft = new Point(points.topLeft.x, points.left.y) points.edgeRight = new Point(points.topRight.x, points.right.y) points.edgeTop = new Point(0, points.topLeft.y)

points.edgeLeftCp = points.edgeLeft.shiftFractionTowards(points.topLeft, 0.5) points.edgeRightCp = points.edgeLeftCp.flipX() points.edgeTopLeftCp = points.edgeTop.shiftFractionTowards( points.topLeft, 0.5 ) points.edgeTopRightCp = points.edgeTopLeftCp.flipX()

/*

• Now, adapt our rect path so it's no longer a rectangle: */ paths.rect = new Path() .move(points.edgeTop) .curve(points.edgeTopLeftCp, points.edgeLeftCp, points.edgeLeft) .line(points.bottomLeft) .line(points.bottomRight) .line(points.edgeRight) .curve(points.edgeRightCp, points.edgeTopRightCp, points.edgeTop) .close()

// Round the straps const strap = points.edgeTop.dy(points.top)

points.tipRight = points.edgeTop.translate(strap / 2, strap / 2) points.tipRightTop = new Point(points.tipRight.x, points.edgeTop.y) points.tipRightBottom = new Point(points.tipRight.x, points.top.y)

macro("round", { id: "tipRightTop", from: points.edgeTop, to: points.tipRight, via: points.tipRightTop, hide: false }) macro("round", { id: "tipRightBottom", from: points.tipRight, to: points.top, via: points.tipRightBottom, hide: false })

return part }

</Example>