In addition to the basic UV Mapping funtions there are some additional functions for mapping surfaces.
Since it is generally undesirable to export every single facet of a surface as an individual 2D part the Surface functions are designed to gather groups of facets to create Segments of the 3D object. The resulting segment can then be converted into editable 2D parts.
The functions and ther purpose are as follows:
Quick Selection: Selects a contiguous series of facets based on the setting in the UV Mapping Options.
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