Sheet Lightning has 3 major file types defined by the file extension:
*.grd - Design Files hold Sheet Lightning 3D CAD designs, creating by saving a design from the 3D CAD
designer. The file is in a binary format and cannot therefore be read with an editor.
*.grp - Parametric Design Files in exactly the same format as '*.grd' files, holding a Sheet Lightning 3D
CAD design in binary format. Files are named with a 'grp' extension to indicate that they form one of two
files used to define a parametric design. Any 'grp' file should therefore also have an accompanying 'par'
file (see next) stored with it to define the parameters that have been attached to the design in this file. A
'grp' file can be loaded into the CAD design system in exactly the same way as the 'grd' file (not available
in the Lite version), but it is unadvisable to alter the design without a good understanding of the impact on
the design parametrics.
*.par - Parametric parameter files. A 'par' file accompanies each 'grp' (Parametric Design) file of the same
name and stored in the same directory. Both files are created when the design is saved from the
parametric designer. Together the two files define the design and the parameters that have been attached
to it using the 'Convert to Parametric' command in the 3D designer. The 'par' file is a text file and can
therefore be loaded into an editor and read, or altered. However the file should have a particualr format
and the parameters in the design file should have some correlation to the associated design. It is therefore
not advisable to alter th parametric file directly without a good undertanding of the impact of the
alterations on the associated design. For a fuller understanding of the parametric file format see - Parametric File Format .