# Cadcorp SIS Desktop Express

These instructions are based on Cadcorp SIS Desktop Express 9.0.2511 and assume you have set the default coordinate reference system to British National Grid (EPSG 27700). These instructions also work for the fully licenced version of Cadcorp SIS Desktop.

## Loading and displaying the GML supply <a href="#id-5.1-loading-and-displaying-the-gml-suppl" id="id-5.1-loading-and-displaying-the-gml-suppl"></a>

There are two ways to load the GML supply into Cadcorp SIS Desktop: You can use drag and drop or add and overlay.

### Using drag and drop <a href="#id-5.1.1-using-drag-and-drop" id="id-5.1.1-using-drag-and-drop"></a>

To load and display the GML supply using drag and drop:

1. Open an existing project or create a new one.
2. In the file system on your computer system (for example, in Windows Explorer), select the GML data (.gz file).
3. Drag and drop the file directly into the Map area in Cadcorp SIS Desktop.

*Data processing will begin automatically. You can monitor the progress by watching the spinning blue circle in the bottom left of the UI.*

When processing is complete, the data will display in the Maps panel and Map area.

Cadcorp produces their own OS MasterMap Topography styling, which automatically styles your OMMM Topography data. If you cannot see your data, zoom to > 1:4,000 scale and it should become visible.

<figure><img src="/files/HvtHHSSBrjZLoLg6sbLg" alt="Cadcorp SIS Desktop showing loaded OSMM Topography Layer GML data" width="563"><figcaption><p>Cadcorp SIS Desktop showing loaded OSMM Topography Layer GML data</p></figcaption></figure>

### Adding an overlay <a href="#id-5.1.2-adding-an-overlay" id="id-5.1.2-adding-an-overlay"></a>

To load and display the GML supply by adding an overlay:

1. Open an existing project or create a new one.
2. From the Home tab, click *Add Overlay*.<br>

   <figure><img src="/files/zvISFcW4eSSii0G4GOSK" alt="Cadcorp SIS Desktop UI showing Home > Add Overlay action"><figcaption><p>Cadcorp SIS Desktop UI showing <em>Home > Add Overlay</em> action</p></figcaption></figure>
3. In the Overlay Types dialog:
   * Click *Files* in the left navigation menu.
   * Click *File* in the options on the right.
   * Click *Next>*.

<figure><img src="/files/PrF1naAbQ7yzyOupDWfN" alt="Cadcorp SIS Desktop Overlay Types dialog with the Files > File option selected" width="433"><figcaption><p>Cadcorp SIS Desktop Overlay Types dialog with the <em>Files > File</em> option selected</p></figcaption></figure>

4. In the File Browser dialog:
   1. Navigate to and select the GML data (.gz file) you want to load.
   2. Click *Finish*.

<figure><img src="/files/8Ll9IdOvd8iqMZF3brjD" alt="Cadcorp SIS Desktop File Browser dialog showing OSMM Topography Layer GML files" width="446"><figcaption><p>Cadcorp SIS Desktop File Browser dialog showing OSMM Topography Layer GML files</p></figcaption></figure>

*Data processing will begin automatically. You can monitor the progress by watching the spinning blue circle in the bottom left of the UI.*

When processing is complete, the data will display in the Maps panel and Map area.

Cadcorp produces their own OS MasterMap Topography styling, which automatically styles your OMMM Topography data. If you cannot see your data, zoom to > 1:4,000 scale and it should become visible.

<figure><img src="/files/lw3o09aa6Y6iQCJ5XdGH" alt="Cadcorp SIS Desktop showing loaded OSMM Topography Layer GML data" width="563"><figcaption><p>Cadcorp SIS Desktop showing loaded OSMM Topography Layer GML data</p></figcaption></figure>


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