# Position matrix on LineGeometry

**URL:** <https://discourse.threejs.org/t/position-matrix-on-linegeometry/81456>\
**Category:** Questions\
**Tags:** geometry\
**Created:** [April 21, 2025, 10:39am UTC](https://discourse.threejs.org/t/position-matrix-on-linegeometry/81456 "2025-04-21T10:39:55Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![IgorBarcelos](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.threejs.org/igorbarcelos/32/52040_2.png) [@IgorBarcelos](https://discourse.threejs.org/u/IgorBarcelos)\
**Post date:** [April 21, 2025, 10:39am UTC](https://discourse.threejs.org/t/position-matrix-on-linegeometry/81456/1 "2025-04-21T10:39:55Z")

</div>

I’m creating a straightforward equilateral triangle using Line2 and LineGeometry like this :

```javascript
const positions = [];

    for (let i = 0; i < 3; i++) {
      const angle = (i * 2 * Math.PI / 3) + Math.PI / 6;
      const x = this.centerPoint.x + this.radius * Math.cos(angle);
      const z = this.centerPoint.z + this.radius * Math.sin(angle);
      positions.push(x, this.centerPoint.y, z);
    }
    positions.push(positions[0], positions[1], positions[2]);

    
    this.geometry.setPositions(positions);
    this.mesh?.computeLineDistances();
    this.material.resolution.set(window.innerWidth, window.innerHeight);
  }

```

It’s working fine.  
The problem is that when I look back to the created object, I don’t see the positions matrix as I’ve set it up. What I get is something like :

 ![image](https://canada1.discourse-cdn.com/flex035/uploads/threejs/original/3X/c/b/cb6789289fb5ad07e3fab17e95f697195361fc97.png)

Can someone explain why?

---

<div class="post-metadata">

**Author:** ![prisoner849](https://yyz1.discourse-cdn.com/flex035/user_avatar/discourse.threejs.org/prisoner849/32/535_2.png) [@prisoner849](https://discourse.threejs.org/u/prisoner849)\
**Post date:** [April 21, 2025, 10:52am UTC](https://discourse.threejs.org/t/position-matrix-on-linegeometry/81456/2 "2025-04-21T10:52:11Z")

</div>

All the data about positions of lines is in these attributes: `instanceStart`, `instanceEnd`. 🤔