[freearchitecture] x3d-cad vs. step

[Terry Hancock]

Lars Grobe wrote:

>One note on the format to store models. There is a x3d-cad specification,
>and it is in development. It is also available without paying fees. And
>there are already lots of apps for x3d. Blender supports some x3d-export
>right now. It is already xml.
>
>So, this is a real question, what about using x3d-cad instead of step?
>  
>
Well, my question is, 'are they really comparable?'

STEP is a large, modular standard, and it covers a range of use-case
based engineering domains.

OTOH, STEP is probably "overbuilt", being, as it is, a committee-based
ISO standards product.

Does X3D-CAD support just geometry, or the whole range of engineering
data?  STEP has a number of representational features that make
it useful, not only for specifying geometry, but also tolerances and
materials, and lots of other stuff.

I imagine that any realistic CAD system, even if it implemented STEP
would have to concentrate on a *subset* of STEP.  But, is that subset
equivalent to what X3D-CAD represents?

I'm really not in a position to compare these things, but I want to
raise the questions if a choice would have to be made.

I think one of the great weaknesses of a community-developed CAD
system, is that the developer community doesn't really have a lot
of experienced industry-based engineers. So, naturally, we don't know
what experienced engineers want.  We can imagine "toy" CAD application,
and so that's what we're inclined to create.

But if we do that, we are doomed to fall far short of the mark.

STEP was created by industry input from many, many engineers and
engineering companies. It therefore represents something close to
a *complete* set of the things that engineers need to represent. It's
quite comprehensive.

Because of that, I think STEP sets a high target for what a free CAD
system ought to aspire to.  Even if in the end, the format chosen is
not STEP or Express-based, I think that the question of representing
what STEP can represent is important (or eventually being able to,
anyway).

BTW, you didn't post a link, but here's one:

http://www.web3d.org/x3d

Looks like X3D is backed by the W3C which is itself a strong
recommendation, based on the number of successful free standards
they have created, and it is also XML-based, which means there's
lots of good free tools for handling the data.

I'm warming up to the idea. ;-)

Cheers,
Terry

-- 
Terry Hancock (hancock at AnansiSpaceworks.com)
Anansi Spaceworks http://www.AnansiSpaceworks.com