SHGmap

About

UPDATE: This functionality is now available directly in StatsHunters (you can download Garmin IMG from the download menu). I’m keeping this extension here only as a fallback in case the built-in option stops working or has issues in the future. If everything works for you in StatsHunters, you don’t need this extension.

This extension enhances the StatsHunters website by adding a new option to the download menu. 
This allows you to export all missing tiles within a 124x124 square around the current map center directly into a Garmin-compatible IMG file with a single click.

How to use:
1.  Navigate to your heatmap on statshunters.com
2.  Make sure your explore tiles are visible (Display settings → Show explore tiles).
3.  Click the download button and select the "Garmin IMG (missing tiles) [shgmap]" option.
4.  Click "Download". The extension will export a 'sh-gmap.img' file containing your missing tiles.

Installing the map on your Garmin device:
1.  Connect your Garmin device to your computer (either as a USB storage device or using an application like OpenMTP).
2.  Copy the downloaded 'shgmap.img' file into the main 'Garmin' folder on your device.
3.  Disconnect your device. The new "SH Missing Tiles" map layer should now be visible.

By default, the gridlines are solid, dark red, and 1 pixel thick, and are visible on map scales up to 12km.
If the map layer is not visible, you may need to enable it in your device's settings (e.g., Profile → Navigation → Map → Map Information).

For larger map areas, the generation process might take a few moments.