AWIPS uses a hierarchical system known as *Localization* to configure many aspects of EDEX and CAVE, such as available menu items, color maps, and derived parameters. This system allows a user to override existing configurations and customize CAVE. For example, a _**User**-level_ localization file will supercede any similar file in a higher level (such as **Site**).
The Localization Perspective acts as file editor for the XML, Python, and text files which customize the look and feel of CAVE. This perspective is available in the menu **CAVE > Perspective > Localization**.
There may be several versions of each file including **BASE**, **CONFIGURED** (GFE only), **SITE**, and **USER**. Each file version is listed separately under the actual file name.
The **_File Editor_** view opens the selected configuration file in an appropriate editor. For example, a Python file is opened in a Python editor, and an XML file is opened in an XML editor.
Navigate to **D2D > Menus** and select a submenu (e.g. **satellite**). This directory lists all of the menu file contributions made by this data plugin. Most data menu directories will have an `index.xml` file from which you can investigate the menu structure and make needed changes.
Selecting a file such as `index.xml` (by double clicking, or expanding) will show a sub-menu with a default localization level (typically **BASE** or **CONFIGURED**). Double-click this file to open in the file editor (you may need to click **Source** at the bottom of the view to see the raw XML). Right-click this file and select **Copy To** > **User (_username_)** and you will see the file localization versions update with the new copy. Select this file to edit, and override, the existing version.
In the Localization Perspective, navigate to ‘**NCEP - Predefined Area Menus**’, double-click ‘**AreaMenus.xml**’, and then right-click ‘**BASE**’ and select ‘**Copy To - User**’.
Now you can either copy and paste an existing xml area file, or simple create one in the NCP. Switch back to the NCP, and select ‘**Area - World**’ to load a known Mercator projection. Zoom in to the continental United States and then from the menu bar select ‘**File - Save Area**’ and name it **CONUS_Mercator** so it matches the name string given in the above AreaMenuItem.
You can switch back to the Localization Perspective to confirm that the file was saved. It will be viewable under **NCEP - Predefined Areas** and, in this example, be called **CONUS_Mercator.xml**.
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CAVE needs to be restarted in order for the new menu item to show up under the NCP **Area** menu.
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Switch to the new Area to confirm.
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On your workstation you can find the new USER localization files in ~/caveData