[Korea-chapter] CAD Working Group meeting (17:00 PST, January 9th) - minutes

[Hyokwang Lee]

Attendees : Don Brutzman, Vincent Marchetti, Myeong Won Lee, Hyokwang Lee

> CAD Working group meeting is on January 9th Wed at 5:00pm PST.
> (January 10th Thu at 10:00am KST)
>
> Agenda items for CAD WG teleconference are as follows.
>
> - Work in progress (to be discussed if necessary)
>
>  * NURBS component (Vince & Don)
Vince and Don plan to integrate Vince's improved NURBS code into the NPS 
branch of Xj3D.
We will dial into the Web3D Conference call line.
- Initial work Tuesday 15 January 1000 PST/1300 EST
- Change review Thursday 17 January 1700 PST/2000 EST/1000 KST Friday

We will test code changes against current X3D NURBS examples, which for 
now appear
to be sufficient. Terry Norbraten NPS will confirm that our integration 
of code is OK.

If all that works, then we will report results to X3D public and Xj3D 
source and X3D cad
mailing lists.

>  * CAD working group strategies for NURBS and for B-REPS
Hyo has found some interesting work with OpenGL Tesselation Shader.
- Triangle Tessellation with OpenGL 4.0
http://prideout.net/blog/?p=48
OSU courses CS 419/519 - RenderMan and OpenGL Shaders
- http://web.engr.oregonstate.edu/~mjb/cs519/
- http://web.engr.oregonstate.edu/~mjb/cs519/Handouts/tessellation.1pp.pdf

Referring to the above sites, it was possible to implement a c++ example 
code
for tessellation and rendering of a surface with their control points on 
the fly.

As the current WebGL does not support the tessellation shader, it cannot 
be applied
to the X3DOM. Hope that it might be included in WebGL, then realtime 
tessellation and
rendering of NURBS nodes would be possible in X3DOM!!

Also possibility in JOGL.
http://forum.jogamp.org/OpenGL-4-status-td2969055.html
If it works, we don't have any reason not to apply them to Xj3D!

Not supported in jgeom but Vince has looked a little at that...
there are a lot of open source implementations out there!

We hope to document various NURBS resources of interest to X3D on the wiki.

Hyo, Vince and Dick have been discussing X3D BREPS.
Frow the viewpoint of visualization(ISO TC184/SC4), another BREPS might 
be redundant,
as STEP already has the master/original BREPS version.
NURBS is not included in the CAD interchange profile and doesn't need to 
be necessary.

As before, NURBS is our primary approach for efficient X3D parametric 
surfaces
on desktop and mobile devices. However BREPS still has some worthwhile 
interest,
perhaps as a component for server-side or offline CAD format conversions.

This will be a topic of further discussion in Korea, we will revisit it.

>  * CADFace spec (Don)
We will review (minimalist) CADFace changes in v3.3 during next meeting.

> - TC184/SC4 Issues
We discussed the surprise emergence of JT as a CAD standard from ISO 
TC184/SC4.

Web3D is asking ISO/IEC JTC1/SC24 what are the rules for patents in ISO 
standards.
It is possible that a future inquiry might occur between ISO standards 
committees.
Dick Puk and Don Brutzman are tracking this.

We might invite TC184/SC4 to brief JTC1/SC24 and X3D CAD Working Group
on their new standard.

This will be a good topic of discussion during the Korea meetings.
Perhaps Soonhung Han, the liaison of TC184/SC4 for Web3D, knows more 
that can be shared.

> - Other Issues/News (be welcomed!)
We discussed agenda and dates for upcoming Korea Chapter meetings at end 
of January.
Dick Puk and Anita Havele will be attending.

Vince discussed some of the interesting lessons learned from the 
StampX3D model.
Please see his interesting page.
- Issues arise when a model is too big - 3D printers (at Shapeways and 
elsewhere)
  can't build a 1-meter model.
- X3DOM doesn't render small models - bug or conversion problem?
- Should we consider what would be good metadata guidance for annotating
  how to print a 3D model?
- I would like to write a panel for X3D-Edit that captures the workflow 
of preparing
  a model for printing

> If anyone is not available, please let me know.
>
> I might not be available from 5:00pm to 5:20pm PST for a power outrage 
> drill.
> I think, however, I can make a call. : )
>
> It seems that there is a problem in the wiki page.
> A warning message at the top as followes,
> 'Warning: Invalid argument supplied for foreach() in 
> /home/spi3der/public_html/x3d/wiki/extensions/AntiBot/AntiBot.php on 
> line 56'.
Web3d.org maintenance and upgrade is proceeding, looked like it began 
working
during our call. Seems peppy too (faster, whites are whiter, blues are 
bluer...)
Thanks Len!

Thanks Don for your help for the minutes!

> With best regards,
> Hyokwang Lee
> ================================================================
> - Building a set of example models to confirm correct operation
>   and encourage the evolution of best practices : Teapot illustrations!
> - A cool logo for CAD working group : a good candidate is the Stamp 
> X3D model v2.0!
> ================================================================