Basic Functions – Looking at Overlay Data

This article explains how to view and interact with overlay data using GGP, whether you're working in a Standard View or a script that includes multiple overlays.

🗺️ What Are Overlays?

Overlays are data layers used in GGP to display and manage geographic information. In order to view or edit overlay data, you must first select which overlays to use in your session.

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📌 Selecting Overlays for Viewing

If you're using a Standard View script (which does not contain overlays by default), you'll need to manually choose the overlays to display.

✅ Steps to Select Overlays:

1. Open the Overlay Selection Panel:

   • Click the Select Overlay toolbar button
     — or —

   • Go to Options > Overlays from the main menu.

2. Choose Available Overlays:

   • In the left-hand pane, you'll see a list of available overlays.

   • In the right-hand pane, you'll see overlays selected for the current script.

3. Add Overlays to Display:

   • Click on an overlay in the left-hand pane to highlight it.

   • Click the right arrow (→) to move it into the Selected Overlays list.

Overlays added to the Selected list become background overlays—visible and queryable, but not editable.

4. Adjust Overlay Display Order:

   • Use the up/down arrows to change the display/print order of selected overlays.

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✏️ Selecting a Foreground Overlay (for Editing)

To add or edit data in an overlay, it must be set as the foreground overlay.

How to Set a Foreground Overlay:

• From the Selected Overlays list (right-hand pane):

  1. Highlight the overlay.

  2. Click the Set button.

  3. The overlay name will now appear in the Foreground Overlay box.

— or —

• Use the Set Foreground toolbar button:

  • A list of selected overlays will be shown.

  • Choose the one you want to make active.

Only the foreground overlay can be edited. All others remain read-only.

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👁️ Viewing Overlay Data

Once overlays are selected:

• The overlay names will appear in the map key (if enabled).

• All data from the selected overlays within your current map view will be displayed.

• The display order follows the sequence in the Selected Overlays list.

🔍 To Inspect Data:

• Right-click any graphic object on the map.

• The Overlay Database Form will open, showing data linked to that object.

• If multiple records exist nearby, use the left/right arrows to scroll through:

  • This includes records from different overlays covering the same location.

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🧭 Summary

• Background overlays: Viewable, printable, and queryable.

• Foreground overlay: Editable overlay set for data entry or modification.

• Use the Select Overlay and Set Foreground tools to manage overlays efficiently.

• Right-click objects to see data details.

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