Super-overlays are a form of KML in which data is divided into regions. This allows Google Earth to refresh/request only particular regions of the map when the viewed area changes. Super-overlays are used to efficiently publish large sets of data. MapTiler Engine is able to generate great super-overlays for Google Earth.
Types of Super-overlay
GeoServer supports two types of super-overlays: raster and vector. With raster super-overlays, GeoServer intelligently produces imagery appropriate to the current zoom level and dynamically outputs new imagery when the zoom level changes. With vector super-overlays, feature data is requested for only the visible features and new features are dynamically loaded as necessary. Raster super-overlays require fewer resources on the client, but vector super-overlays have a higher output quality.
When using the KML Reflector, super-overlays are enabled by default, whether the data in question is raster or vector. For more information on the various options for KML super-overlay output, please see the page on the KML Reflector.
Creating overlays for Google Earth in MapTiler Engine
MapTiler Engine can create overlays for Google Earth. Here is how to do it the step-by-step:
- Open the application and choose your file(s).
- If the image is a GeoTIFF, it already has a geolocation inside. If not, you have to specify the Coordinate system and Georeference it. Once the georeferencing is done, proceed by clicking the "Export" button.
- Select "Google Earth KML" as the output format.
- Click on "Continue", and "render", create a new folder, and start rendering. Once the rendering process is finished, the .kml file is available in the rendering folder. You can either view the content of the folder by clicking on the "Open folder" option or open Google Earth directly by clicking on the "Preview the map" option.
- Once the file is opened by the Google Earth application, the map is positioned in the correct location and perfectly overlays the terrain. It is possible to pan, zoom and view it from all sides in 3D.
You can try to create a KML super overlay with the sample image of the Grand Canyon.