writing DXF files for solid 3D objects

I am writing a programme to create DXF files for import into autocad.
I need to create a complex three dimensional object with solid colour.
I have a mesh for the shape I want to make, but I am defeated by the
way that the dxf file format represents world and object co-ordinates.
Can anyone tell me how I translate from a set of (x,y,z) coordinates
into the numbers for the codes (10,20,30 etc .... 210,220,230)
necessary for the SOLID object.

Thanks

Trevor

 

First, there are 3, very different possibilities in AutoCAD when you
mention the word "solid". I am assuming that you are wanting to deal
with 3D Solids, the way the word is used in most of the CAD industry.

When I looked for info on the 3d solids, I spoke with a few other
folks who have attempted this. What they said they ran into was the
problem that the ACIS solids is in a propriatary format which they
couldn't find info on.

Sorry I couldn't be of more help. But, apparently this is a
difficult thing to do. The Open DWG alliance might be of more help.

 

To write 3DSOLIDS for import into Acad, try ACIS .SAT file format.
I believe You may get a free of charge (for 1 year) code library from
the supplier see http://www.spatial.com

There is a free dowloadable .sat file viewer (7-8Mb)
which You may use as a file checker.

Hallstein

 

Just brainstorming here... but one way around the ACIS issue is to
create the import file via a Script file. This is a text file with
the command line sequence necessary to create the object. You need to
be very well versed in AutoCAD to do this, and probably must have
access to Autocad itself while you are working it out.