This function can also be accessed in the Global Mapper File toolbar.
This Function Can be used with Ctrl+O on your keyboard.
The Open Data File(s) command allows the user to open additional data files into the main Global Mapper view.
If no other data is already loaded and the user has not explicitly set a projection, the view will adopt the projection and datum of the first data file selected for loading. If other data is already loaded, the selected data files will be displayed in the current projection/datum.
The data will automatically be displayed at the proper location relative to other loaded data, creating a mosaic of data that is properly placed spatially.
You don't have to do anything special to create mosaics of multiple files, this happens simply by loading the geo-referenced files into Global Mapper.
Note: Global Mapper automatically opens files with tar.gz extensions without the use of a decompression tool such as Winzip. This is particularly useful for SDTS transfers, which are typically distributed in a .tar.gz format.