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

---
title: utils.beamIntersectsY()
---

The `utils.beamIntersectsY()` function finds the intersection between an endless
line and a given Y-value. Returns a [Point](/reference/api/point) object for
the intersection, or `false` there is no intersection.

## Signature

```js
Point | false utils.beamIntersectsY(Point A, Point B, float Y)
```

## Example

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

  points.A = new Point(10, 10)
  points.B = new Point(50, 40)
  
  paths.AB = new Path().move(points.A).line(points.B)
  
  snippets.x = new Snippet(
    "notch", 
    utils.beamIntersectsY(points.A, points.B, 30)
  )
  
  paths.help = new Path()
    .move(new Point(0, 30))
    .line(new Point(50, 30))
    .attr("class", "note dashed")

  return part
}
```
</Example>