freesewing/sites/dev/docs/reference/api/utils/curvesintersect

---
title: utils.curvesIntersect()
---

The `utils.curvesIntersect()` function finds the intersections between two curves
described by 4 points each.

## Signature

```js
array | Point | false utils.curvesIntersect(
  Point startA,
  Point Cp1A,
  Point Cp2A,
  Point endA,
  Point startB,
  Point Cp1B,
  Point Cp2B,
  Point endB)
```

This returns `false` if no intersections are found,
a [Point](/reference/api/point) object if
a single intersection is found, and an array
of [Point](/reference/api/point) objects if
multiple intersections are found.

## Example

<Example caption="A Utils.curvesIntersect() example">
```js
({ Point, points, Path, paths, Snippet, snippets, utils, getId, part }) => {

points.A = new Point(10, 10)
points.Acp = new Point(310, 40)
points.B = new Point(110, 70)
points.Bcp = new Point(-210, 40)

points.C = new Point(20, -5)
points.Ccp = new Point(60, 300)
points.D = new Point(100, 85)
points.Dcp = new Point(70, -220)
paths.curveA = new Path()
.move(points.A)
.curve(points.Acp, points.Bcp, points.B)
paths.curveB = new Path()
.move(points.C)
.curve(points.Ccp, points.Dcp, points.D)

const intersections = utils.curvesIntersect(
points.A,
points.Acp,
points.Bcp,
points.B,
points.C,
points.Ccp,
points.Dcp,
points.D
)

if (intersections) {
if (intersections instanceof Array) {
for (const p of intersections)
snippets[getId()] = new Snippet('notch', p)
} else {
snippets[getId()] = new Snippet('notch', intersections)
}
}

return part
}

```
</Example>
```