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Avoiding overlap

While we've only drawn the end of one strap, it's pretty obvious they overlap, which makes it impossible to cut out, so we're going to have to address that.

Specifically, we're going to rotate our strap out of the way until it no longer overlaps. The rest of our bib should stay as it is, so let's start by making a list of points we need to rotate.

However, there is a catch.

Macros and auto-generated IDs

We have used the round macro to help us round the corners of our strap, and it added a bunch of auto-generated points to our pattern. We need to rotate these points too, but what are their names?

A macro will return the names of the things it created. So far, we have not captured that return value, but if we did, it would look like this:

{
"tipRightTop": {
"points": {
"start": "__macro_@freesewing/plugin-round_tipRightTop_start",
"cp1": "__macro_@freesewing/plugin-round_tipRightTop_cp1",
"cp2": "__macro_@freesewing/plugin-round_tipRightTop_cp2",
"end": "__macro_@freesewing/plugin-round_tipRightTop_end"
},
"paths": {
"path": "__macro_@freesewing/plugin-round_tipRightTop_path"
}
},
"tipRightBottom": {
"points": {
"start": "__macro_@freesewing/plugin-round_tipRightBottom_start",
"cp1": "__macro_@freesewing/plugin-round_tipRightBottom_cp1",
"cp2": "__macro_@freesewing/plugin-round_tipRightBottom_cp2",
"end": "__macro_@freesewing/plugin-round_tipRightBottom_end"
},
"paths": {
"path": "__macro_@freesewing/plugin-round_tipRightBottom_path"
}
}
}

Those names aren't very handy to remember. So I will rewrite this code a bit to we'll capture these return values from the round macros and create easy-to-remember points from them:

function draftBib({
Path,
Point,
paths,
points,
measurements,
options,
utils,
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)

/*
* 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()

// 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)

/*
* Macros will return the auto-generated IDs
*/
const ids1 = {
tipRightTop: macro("round", {
id: "tipRightTop",
from: points.edgeTop,
to: points.tipRight,
via: points.tipRightTop,
hide: false
}),
tipRightBottom: macro("round", {
id: "tipRightBottom",
from: points.tipRight,
to: points.top,
via: points.tipRightBottom,
hide: false
})
}

/*
* Create points from them with easy names
*/
for (const side in ids1) {
for (const id of ['start', 'cp1', 'cp2', 'end']) {
points[`${side}${utils.capitalize(id)}`] = points[ids1[side].points[id]].copy()
}
}

/*
* 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()

return part
}

It looks the same as before, but now those macro points are accessible to us

Once we have our list of points to rotate, we can rotate them. How far? Until the strap no longer overlaps.

function draftBib({
Path,
Point,
paths,
points,
measurements,
options,
utils,
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)

/*
* 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()

// 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)

/*
* Macros will return the auto-generated IDs
*/
const ids1 = {
tipRightTop: macro("round", {
id: "tipRightTop",
from: points.edgeTop,
to: points.tipRight,
via: points.tipRightTop,
hide: false
}),
tipRightBottom: macro("round", {
id: "tipRightBottom",
from: points.tipRight,
to: points.top,
via: points.tipRightBottom,
hide: false
})
}

/*
* Create points from them with easy names
*/
for (const side in ids1) {
for (const id of ['start', 'cp1', 'cp2', 'end']) {
points[`${side}${utils.capitalize(id)}`] = points[ids1[side].points[id]].copy()
}
}

/*
* This is the list of points we need to rotate
* to move our strap out of the way
*/
const rotateThese = [
"edgeTopLeftCp",
"edgeTop",
"tipRight",
"tipRightTop",
"tipRightTopStart",
"tipRightTopCp1",
"tipRightTopCp2",
"tipRightTopEnd",
"tipRightBottomStart",
"tipRightBottomCp1",
"tipRightBottomCp2",
"tipRightBottomEnd",
"tipRightBottom",
"top",
"topCp2"
]
/*
* We're rotating all the points in
* the `rotateThese` array around
* the `edgeLeft` point.
*
* We're using increments of 1 degree
* until the `tipRightBottomStart` point
* is 1 mm beyond the center of our bib.
*/
while (points.tipRightBottomStart.x > -1) {
for (const p of rotateThese) points[p] = points[p].rotate(1, points.edgeLeft)
}

/*
* This is not needed
* we are merely adding it to show
* what the rotated path looks like
*/
macro("round", {
id: "showRightTop",
from: points.edgeTop,
to: points.tipRight,
via: points.tipRightTop,
hide: false,
classes: 'contrast dotted',
})
macro("round", {
id: "showRightBottom",
from: points.tipRight,
to: points.top,
via: points.tipRightBottom,
hide: false,
classes: 'contrast dotted',
})
/*
* 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()

return part
}

It is looking pretty wonky now, but we'll deal with that next