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Drawing Database Compatibility
In drawing database compatibility, PowerCAD provides these features:
DWG Roundtrip. If you open an AutoCAD drawing, you now have the possibility to "Roundtrip" all unsupported AutoCAD entities. That means, that while being edited in PowerCAD, unsupported AutoCAD entities remain unchanged and invisible. If the drawing is saved in AutoCAD drawing format again, all entities including these unsupported AutoCAD entities will be written back to the file. "Roundtripped" AutoCAD Entities include:
ARCALIGNEDTEXT
BODY
IMAGE
MLINE
PROXY
RAY
REGION
RTEXT
SOLID3D
WIPEOUT
XLINE
XRECORD-OBJECTS
Може би е това.