Free Geography Tools

Last week, I covered my KML Screen Overlay Maker utility, which simplifies the job of converting graphics into Google Earth screen overlays. It occurred to me that this utility could be used in conjunction with the free utility EarthPaint to create screen overlays. I’ve covered EarthPaint before - it’s a useful tool for creating Google Earth ground overlay files using vector-graphic-like drawing tools (lines, circles, ellipses, polygons, text, etc.). But the graphic file it generates can be used along with the KML Screen Overlay Maker to create a screen overlay instead of a ground overlay.

1. Start up EarthPaint; Google Earth will start up at the same time.

2. You’ll be given the option to either use the current location in Google Earth, or set a new one. Doesn’t matter which one you choose, since you’ll be creating a fixed screen overlay.

3. EarthPaint will load in a black-and-white image of the current view in Google Earth. Use this image as a guide as you draw the elements you want in your screen overlay, with the edges of the image defining the limits of the screen overlay graphic. There’s more info on this in my original EarthPaint post.

4. When done, click on Create => Send to Google Earth. You’ll be asked to enter a name for the overlay graphic; after clicking OK, the graphic image you created in step 3 will be opened in Google Earth as a ground overlay. It’s a GIF file with transparency, which makes it perfect for creating a screen overlay.

5. Go to the program directory for EarthPaint (default is C:\Program Files\EarthPlot Software\EarthPaint. Open the “Cache” subdirectory, and look for a GIF file that has the name assigned in step 4. Copy this GIF file to another location.

6. Start up the KML Screen Overlay Maker, and select the GIF graphic file from step 5.

7. Leave the Overlay Size units, x and y, as fraction, and enter “1″ for the value of both of those. This will automatically resize the overlay graphic to fit to the edges of the view in Google Earth. Leave everything else as is.

8. Save the file, and then open it up in Google Earth (with the Network Link option in KML Screen Overlay Maker if you want). You should now see the graphic image created in step 3 as a screen overlay that doesn’t move as you change the view in Google Earth.