Hi all, Tedds discovery is also what they discovered when they worked out the file format for DXF files in 804 AD. > Table 11-13. Group 70 bit codes for Polyline entity > +======================================================+ > | Flag bit | Meaning | > | value | | > |----------|-------------------------------------------| > | 1 | This is a closed Polyline (or a polygon | > | | mesh closed in the M direction) | > |----------|-------------------------------------------| > | 2 | Curve-fit vertices have been added | > |----------|-------------------------------------------| > | 4 | Spline-fit vertices have been added | > |----------|-------------------------------------------| > | 8 | This is a 3D Polyline | > |----------|-------------------------------------------| > | 16 | This is a 3D polygon mesh. | > | | Group 75 indicates the smooth surface type| > | | as follows: | > | | 0 = no smooth surface fitted | > | | 5 = quadratic B-spline surface | > | | 6 = cubic B-spline surface | > | | 8 = Bezier surface | > |----------|-------------------------------------------| > | 32 | The polygon mesh is closed in the N | > | | direction | > |----------|-------------------------------------------| > | 64 | This Polyline is a polyface mesh | > |----------|-------------------------------------------| > | 128 | The linetype pattern is generated | > | | continuously around the vertices of | > | | this Polyline | > +------------------------------------------------------+ Dats the same type of thing isn't it? Also, just because Tedd rediscovered this, doesn't demean his work. It probably took Autocad 1200 years to work that out, and perhaps that's why they won't let the rest of the silly file format drop:-) JC ========================================================================== John Clark Aeronaut Automation 30 Kennedy Place Bayview 2104 Australia Phone: 61 2 99 97 28 42 Fax: 61 2 99 79 56 15 email: JohnC@... http://www.AeronautAuto.com ========================================================================== ========================================================================== John Clark Aeronaut Automation 30 Kennedy Place Bayview 2104 Australia Phone: 61 2 99 97 28 42 Fax: 61 2 99 79 56 15 email: JohnC@... http://www.AeronautAuto.com ==========================================================================