---
title: "CoordsMarker"
section: "Components"
order: 38
description: "CoordsMarker — Vuer documentation"
---

import { DocImage } from '@docs/components/Docs'

# CoordsMarker

The `CoordsMarker` component displays 3D coordinate axis markers. This is ideal for:

- Visualizing coordinate frames and orientations
- Debugging transformations and poses
- Showing robot joint frames
- Creating reference markers in scenes

<DocImage src="/source/components/figures/coords_marker.png" alt="" />

## Basic Usage

A minimal example that creates coordinate markers:

```python
import asyncio
from vuer import Vuer
from vuer.schemas import DefaultScene, CoordsMarker, OrbitControls

app = Vuer()

n = 10
N = 1000

@app.spawn(start=True)
async def main(session):
    markers = [
        CoordsMarker(
            position=[i % n, (i // n) % n, (i // n ** 2) % n],
            scale=0.25,
        )
        for i in range(N)
    ]

    session.set @ DefaultScene(
        *markers,
        bgChildren=[
            OrbitControls(key="OrbitControls")
        ],
    )

    while True:
        await asyncio.sleep(1.0)
```

## Key Parameters

| Parameter   | Type  | Default   | Description                                                             |
| ----------- | ----- | --------- | ----------------------------------------------------------------------- |
| `key`       | str   | -         | Unique identifier for the marker                                        |
| `position`  | list  | `[0,0,0]` | Marker position in world coordinates                                    |
| `rotation`  | list  | `[0,0,0]` | Marker rotation (Euler angles)                                          |
| `matrix`    | list  | -         | 4x4 transformation matrix (16 numbers). Overrides position and rotation |
| `scale`     | float | `1.0`     | Overall marker size                                                     |
| `headScale` | float | `1.0`     | Scale factor for the arrow heads                                        |
| `lod`       | int   | -         | Level of detail - number of segments for the cone and stem              |