Step-by-Step Guide: Creating a Google Earth ScreenOverlay

To master the Google Earth ScreenOverlay, you must use Keyhole Markup Language (KML) code, as the standard Google Earth Pro graphical user interface only allows you to author Ground Overlays (which drape over the geography and move when you pan). A ScreenOverlay fixes an image (like a map legend, North arrow, logo, or banner) to a specific spot on your screen, keeping it perfectly stationary while you navigate the globe. 🛠️ Step 1: Base KML Structure

Because you cannot click a button to build a ScreenOverlay, you must copy a base block of KML text, modify it in a text editor (like Notepad or TextEdit), and paste it directly into Google Earth Pro. Paste this baseline template into your text editor:

<?xml version=“1.0” encoding=“UTF-8”?> My Custom Map Legend https://yourwebsite.com Use code with caution.

📐 Step 2: Mastering the Coordinate Logic (overlayXY and screenXY)

Positioning your overlay relies entirely on mapping a specific anchor point on your image () to a matching anchor point on your monitor (). : Defines the point on your image asset.

: Defines the point on your Google Earth application window. Coordinate Cheat Sheet

Using fraction units simplifies scaling across different screen sizes, where (0,0) is the bottom-left and (1,1) is the top-right: Screen Position overlayXY Configuration screenXY Configuration Bottom-Left Corner x=“0” y=“0” x=“0.05” y=“0.05” (Offsets 5% from edges) Bottom-Right Corner x=“1” y=“0” x=“0.95” y=“0.05” Top-Left Corner x=“0” y=“1” x=“0.05” y=“0.95” Top-Right Corner x=“1” y=“1” x=“0.95” y=“0.95” Dead Center x=“0.5” y=“0.5” x=“0.5” y=“0.5” 📏 Step 3: Controlling Size and Rotation

Prevent Distortion (): Setting both x=“0” y=“0” forces Google Earth to display your image at its original native pixel dimensions.

Forced Dimensions: To force a exact size, use x=“200” y=“150” xunits=“pixels” yunits=“pixels”.

Dynamic Scaling: Setting x=“0.2” y=“0” xunits=“fraction” will make the overlay exactly 20% of the screen’s width while automatically preserving the aspect ratio.

Rotation: To tilt a banner or map compass, use 45 inside the ScreenOverlay block. The tag dictates the pivot point of the asset (set x=“0.5” y=“0.5” to rotate directly around its center). 💾 Step 4: Importing and Deploying Your Overlay

Prep your asset: Design your map legend or logo in software like GIMP or Photoshop, keeping the background transparent. Export it cleanly as a PNG file.

Edit your KML text: Swap out the tag path. You can reference a live web URL or point directly to a local hard drive image file (e.g., C:/Maps/legend.png).

Inject into Google Earth Pro: Select and copy your finished KML text code string. Open Google Earth Pro, click directly onto your Temporary Places folder in the left sidebar, and press Ctrl+V (or Cmd+V on Mac). Your stationary image will snap onto your viewing screen instantly.

Package for sharing: Right-click your temporary project folder containing your geometry and the new ScreenOverlay, and select Save Place As…. Crucial: Choose KMZ format rather than KML. KMZ creates a compressed archive file that embeds your PNG image inside it, ensuring that whoever opens your map can see the overlay.

For official technical deep-dives on nested tag configurations, review the Google Earth Screen Overlays Outreach Tutorial.

I can write out the exact KML coordinates to match your targeted layout.