The following group codes apply to LAYER symbol table entries. In addition to the group codes described here, see "Common Group Codes for Symbol Table Entries." For information about abbreviations and formatting used in this table, see "Formatting Conventions in This Reference."
LAYER group codes
Group code Description
100 Subclass marker (AcDbLayerTableRecord)
2 Layer name
70 Standard flags (bit-coded values):
1 = Layer is frozen; otherwise layer is thawed.
2 = Layer is frozen by default in new viewports.
4 = Layer is locked.
16 = If set, table entry is externally dependent on an xref.
32 = If this bit and bit 16 are both set, the externally dependent xref has been successfully resolved.
64 = If set, the table entry was referenced by at least one entity in the drawing the last time the drawing was edited. (This flag is for the benefit of AutoCAD commands. It can be ignored by most programs that read DXF files and need not be set by programs that write DXF files.)
62 Color number (if negative, layer is off)
6 Linetype name
290 Plotting flag. If set to 0, do not plot this layer
370 Lineweight enum value
390 Hard pointer ID/handle of PlotStyleName object
Xref-dependent layers are output during SAVEAS. For these layers, the associated linetype name in the DXF file is always CONTINUOUS.