> For the complete documentation index, see [llms.txt](https://cityweft.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cityweft.gitbook.io/docs/geometry/surface.md).

# Surface

Geometry Type:  <mark style="color:blue;">`meshes`</mark>&#x20;

```javascript
{
     "type": "surface",
     "geometryType": "meshes",
     "meshes": Mesh[]
},
```

What does a surface mesh element contain? This is the example:

```javascript
{
     // The most important element of any meshed geometry for visualization
     "vertices": [x1, y1, z1, x2, y2, z2, ...],
     "type": string
},
```

### Available types

| Type                     | Description                      |
| ------------------------ | -------------------------------- |
| **asphalt**              | Paved surfaces like roads        |
| **roadwayIntersection**  | Junctions of roads               |
| **pavement**             | Footpaths or sidewalks           |
| **water**                | Bodies of water                  |
| **farmland**             | Agricultural land                |
| **grass**                | General grassy surfaces          |
| **sand**                 | Sandy areas                      |
| **rock**                 | Rocky terrain                    |
| **pitch**                | Sports fields                    |
| **manicuredGrass**       | Well-maintained lawns            |
| **helipad**              | Helicopter landing areas         |
| **forest**               | Densely wooded areas             |
| **garden**               | Decorative or functional gardens |
| **construction**         | Areas under construction         |
| **buildingConstruction** | Building sites                   |
| **shrubbery**            | Areas with shrubs                |
| **roadwayArea**          | Areas designated for roads       |

{% hint style="warning" %}
When a topography model is requested, all surfaces are projected onto it, which can significantly increase the size of the resulting surface data. To optimize performance, consider disabling projection when it’s not needed. More info [Customizations](/docs/basics/customizations.md)
{% endhint %}

<figure><img src="/files/OrUqtfVuSKDs93hjKIqV" alt=""><figcaption><p>Projected Surfaces</p></figcaption></figure>

An example of filtering by type in Three.js:

```javascript
const material = new THREE.MeshStandardMaterial({
  color: mesh.descriptor.type === "asphalt" ? "#dc0d0d" : getRandomColour(),
});
```

<figure><img src="/files/rJ8Di7fXQbDXXnE7ruI9" alt=""><figcaption></figcaption></figure>


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