DGNLib is a small C/C++ library for reading and writing Microstation DGN files (also known as ISFF format). Microstation DGN files are CAD files similar to AutoCAD's DWG.
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This release implements 2D write support, fixes bugs (color tables,
spatial queries, DGNFreeElement()for tags), adds support for ViewInfo
from TCB, and associates IDs in attribute linkages.