> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-apis/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-apis/accessing-os-apis/os-ngd-api-features/getting-started/gis-software/cadcorp-sis.md).

# Cadcorp SIS

The Cadcorp Spatial Information System® (Cadcorp SIS®) is an integrated family of geospatial products comprising desktop, web, and developer applications.

Cadcorp SIS Desktop connects directly to the OS Data Hub through dedicated wizards.

## What you need

* Cadcorp SIS (version SIS 9 or later).
* A preloaded base map, for example, [OS Maps API](/os-apis/accessing-os-apis/os-maps-api.md) or [OS Vector Tile API](/os-apis/accessing-os-apis/os-vector-tile-api.md).
* OS NGD API – Features added to an API project in the OS Data Hub with an API Key. See [Getting started with an API project](/os-apis/core-concepts/getting-started-with-an-api-project.md) for more information.

## Instructions

{% hint style="info" %}
These instructions are based on Cadcorp SIS Desktop version 9.1.1668.
{% endhint %}

{% stepper %}
{% step %}

### Add overlay

Once a new map has been set up, in the Home tab, click *Add Overlay*.

<figure><img src="/files/4e750bbe5d2c441fa18e38eb6f584a1abb2641f0" alt="Cadcorp SIS Desktop UI highlighting Add Overlay button."><figcaption><p>Cadcorp SIS Desktop UI highlighting the Add Overlay button.</p></figcaption></figure>
{% endstep %}

{% step %}

### Select API

In the Overlay Types dialog:

* Select *Ordnance Survey (GB) > OS (GB) Data Hub*, and then click *Next*.

In the OS (GB) Data Hub dialog:

* Select *OS National Geographic Database (NGD) API*– *Features*.
* **API Key**: Enter your API key.
* **Premium/Public Sector Plan**: Select this option if you have this plan.
* **Save in the UI settings database (encrypted)**: Select this option.
* Click *Next*.

<figure><img src="/files/a3fa0701f3d1ad0f4b47563ed908c34b258d2da5" alt="Cadcorp SIS Desktop OS (GB) Data Hub dialog with the Next button and API Key button highlighted."><figcaption><p>Cadcorp SIS Desktop OS (GB) Data Hub dialog</p></figcaption></figure>
{% endstep %}

{% step %}

### Adding layers to the map

In the OS Data Hub NGD API – Features Data Themes and Feature Types dialog:

* **Well-known ‘recipe’**: Select a predefined recipe, if available.
* **Data Themes**: Select your data themes.
* **Features**: If necessary, use the editing tools (on the right) to delete feature types or to change the order in which they display in your SIS Workspace Definition (SWD).\
  \&#xNAN;*By default, all feature types within the selected data themes are available in the right panel.*
* **Local cache**: Select this option to store the data temporarily on your machine.\
  \&#xNAN;*If you save and reopen the SWD, the data will still be available as it is fetched from your local cache.*
* **One-off import**: Select this option to do a one-off import of the data.\
  \&#xNAN;*If you save and reopen the SWD, the data will not be available and you will need to re-import it. These imports have a larger file size.*
* **Filtering**:\
  \&#xNAN;*These settings are used in conjunction and define how much data is required for display. It is recommended that you always set a spatial filter and feature limit.*
  * **Spatial**: The *Intersect with current view extent* option limits the download to only selected features within the current window extent.\
    \&#xNAN;*You can also load features within a specific area of interest using the polygon feature to draw your area of interest on the map BEFORE opening the Add Overlay dialog.*
  * **Maximum number of features**: Limits the number of feature values downloaded to the number set.\
    \&#xNAN;*This limit is applied per feature within any filtered spatial area.*
* Click *Finish*.

<figure><img src="/files/3e7bab36b313c46d30f51af4e3aba111d5c48620" alt="OS Data Hub NGD API – Features recipe shown in the Data Themes and Feature Types window with Building, Land, RAMI, Water Features and Water Network"><figcaption></figcaption></figure>

*The selected layer(s) will then display in the* SIS Workspace Definition (SWD) *and the data will display in the map area:*

<figure><img src="/files/18e2352929f1172c925f2c495398301c01d38f1e" alt="Cadcorp SIS Desktop UI showing OS NGD API – Features data in the map area."><figcaption><p>Cadcorp SIS Desktop UI showing OS NGD API – Features data.</p></figcaption></figure>
{% endstep %}
{% endstepper %}


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