Re: [brlcad-devel] DWG import

[H.S.Rai <har...@gm...>]

On Wed, Apr 24, 2013 at 8:41 AM, Christopher Sean Morrison
<br...@ma...> wrote:
>
> That's like saying BRL-CAD supports 2D models, because we store them
> in our .g file format.  We do, but we don't do it very well or very often (certainly
> not the default recommended practice).  AutoCAD is the same in that regard,
> but with a 2D focus and poor/rare 3D entities.

OK.

That mean BRL-CAD used .g is for 3D and support 2D to some extent via
dxf, and AutoCAD focused on 2D using DWG, and support 3D to some
extent within DWG. So DWG is more towards 2D, but can handle 3D also.

STEP can handle both 2D and 3D.

>> One more question. Can we used STEP for 2D in place of DXF?
>
> Absolutely, STEP has *extensive* support for 2D entities.  I like to call it
> the mathematical union of all CAD formats.

;-)

>  It can represent pretty much anything.
>
>> As per my understanding STEP is primarily 3D (I hope I am correct)
>> format. But http://en.wikipedia.org/wiki/ISO_10303#Coverage_of_STEP_Application_Protocols_.28AP.29
>> has some pointer about 2D
>
> STEP is a really immense standard, it really does cover nearly everything that
> everyone uses and even a lot that nobody uses yet.

That's really great.

How much BRL-CAD accommodate STEP; 100% or 60% or some thing else?

> AP201 and 202 do describe 2D elements in detail and most of those entities are
> also in the more prevalently supported AP203/209 specifications.

That mean, not all software support STEP completely.

> A librarian I knew tried to obtain "all" of the STEP standard from ISO.  Reportedly,
> ISO warned them that it was going to be a stack of paper about 20-30 feet tall.
> It would have arrived on a couple pallets.  The instead opted for just 5 of the
> more common APs (there are dozens) ...

OMG!

--
H.S.Rai