# Vector tiles overview

OS MasterMap Topography Layer is supplied as a national vector tiles set in six MBTiles files (one file per feature type). This is a lightweight set of tiles that is efficient and fast to render in your software, and which provides high-resolution data and gives a seamless experience when zooming in and out. The data is supplied in Web Mercator projection (ESPG:3857).

## Vector tiles schema <a href="#id-6.1-vector-tiles-schema" id="id-6.1-vector-tiles-schema"></a>

The vector tiles schema is detailed in the following table. In the zoom levels columns within the table, the letter *N* indicates that the specified layer and attribute are not mapped within that zoom level, whereas the letter *Y* indicates that the specified layer and attribute are mapped within that zoom level.

{% hint style="info" %}
*The zoom level is a number that defines how large or small the contents of a vector tiles dataset appear in the viewing pane of a GIS application.*
{% endhint %}

### boundary\_line layer

| Attribute          | Zoom level: 0 to 15 | Zoom level: 16 |
| ------------------ | ------------------- | -------------- |
| toid               | N                   | Y              |
| theme              | N                   | Y              |
| style\_code        | N                   | Y              |
| style\_description | N                   | Y              |
| line               | N                   | Y              |

### cartographic\_symbol layer

| Attribute          | Zoom level: 0 to 15 | Zoom level: 16 |
| ------------------ | ------------------- | -------------- |
| toid               | N                   | Y              |
| theme              | N                   | Y              |
| orientation        | N                   | Y              |
| style\_code        | N                   | Y              |
| style\_description | N                   | Y              |
| point              | N                   | Y              |

### cartographic\_text layer

| Attribute          | Zoom level: 0 to 15 | Zoom level: 16 |
| ------------------ | ------------------- | -------------- |
| toid               | N                   | Y              |
| theme              | N                   | Y              |
| height             | N                   | Y              |
| style\_code        | N                   | Y              |
| style\_description | N                   | Y              |
| colour\_code       | N                   | Y              |
| font\_code         | N                   | Y              |
| rotation           | N                   | Y              |
| geo\_x             | N                   | Y              |
| geo\_y             | N                   | Y              |
| anchor             | N                   | Y              |
| text\_string       | N                   | Y              |
| point              | N                   | Y              |

### topographic\_area layer

| Attribute          | Zoom level: 0 to 15 | Zoom level: 16 |
| ------------------ | ------------------- | -------------- |
| toid               | N                   | Y              |
| theme              | N                   | Y              |
| style\_code        | N                   | Y              |
| style\_description | N                   | Y              |
| polygon            | N                   | Y              |

### topographic\_line layer

| Attribute          | Zoom level: 0 to 15 | Zoom level: 16 |
| ------------------ | ------------------- | -------------- |
| toid               | N                   | Y              |
| style\_code        | N                   | Y              |
| style\_description | N                   | Y              |
| line               | N                   | Y              |

### topographic\_point layer

| Attribute          | Zoom level: 0 to 15 | Zoom level: 16 |
| ------------------ | ------------------- | -------------- |
| toid               | N                   | Y              |
| theme              | N                   | Y              |
| style\_code        | N                   | Y              |
| style\_description | N                   | Y              |
| point              | N                   | Y              |


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