Value

Meaning

1

Extra vertex created by curve-fitting.

2

Curve-fit tangent defined for this vertex. A curve-fit tangent direction of 0 may be omitted from DXF output but is significant if this bit is set.

4

Not used.

8

Spline vertex created by spline-fitting.

16

Spline frame control point.

32

3D polyline vertex

64

3D polygon mesh

128

Polyface mesh vertex