[x3d-public] Extrusions, take 3

[Leonard Daly]

On 1/26/2016 3:21 PM, John Carlson wrote:
> Leonard, I think you forget that Extrusion splines etc. can be 
> animated.  If Maya can export an Extrusion animation to X3D V4.0 and 
> your new elements can handle animation of it, I think we are fine.

In Maya and Blender, extrusions are converted to IndexedFaceSets. These 
can be animated through the usual mechanisms in those applications. The 
results are typically stored in a FBX file. Unfortunately, the FBX 
format is not open and not too conducive to importing in a browser. 
Autodesk provides a C++ and Python API for accessing the file.

Extrusions are just a convenience node for creating a constrained 
IndexedFaceSet. I am working on exactly how X3D fits in the process 
chain from modeling tools to display. The goal is that X3D is an 
declarative archivable format that has a browser-based run time. The 
goal is to not reduce the display capability of X3D in that chain; 
however, not all of the functionality of X3D V3.3 is necessary to remain 
in the node definitions to make that happen.

Animation of the spline and cross-sections of an extrusion is much 
easier for the developer, but puts a much greater load on the run-time 
as it needs to re-triangulate the result on each animation.


Leonard Daly





>
> John
>> On Jan 26, 2016, at 1:47 PM, Leonard Daly <Leonard.Daly at realism.com 
>> <mailto:Leonard.Daly at realism.com>> wrote:
>>
>> I would like to ask the question very differently. My question is not 
>> to ignore the importance of getting the definition correct for X3D <= 
>> V3.3.
>>
>>
>> Most (>95%) 3D modeling is done with a tool. In non-CAD environment, 
>> the tools is almost certainly Maya or Blender. Both of those tools 
>> have extrusions built in to their interface. I imagine CAD tools are 
>> similar. With so many tools providing graphical extrusion editors, 
>> and some of the tools being open-source (at least Blender);
>>
>> Do we need an extrusion node in V4 to support content developed for V4+?
>>
>>
>> Leonard Daly
>>
>>
>>
>> On 1/26/2016 7:15 AM, Alekseyev, Vsevolod (NIH/NIAID) [E] wrote:
>>> Hi X3D community,
>>>
>>> I've tried and failed twice to explain the problems with the 
>>> definition of the Extrusion node. So here's a tl;dr version:
>>>
>>> Dear authors of the X3D standard, please take a careful look at the 
>>> standard and answer me:
>>>
>>> 1) When the spine goes (0,0,0)-(0,-1,0), what is the CSP?
>>> Note: all answers but one will render one of the reference models in 
>>> the Savage archive invalid.
>>>
>>> 2) When the spine goes (0,0,0)-(0,1,0)-(0,0,0), what is the CSP?
>>>
>>> 3) When the spine goes (0,0,0)-(1,1,0)-(1,1,0)-(1,1,0)-(2,0,0), what 
>>> is the CSP for the three middle points?
>>>
>>>
>>> _______________________________________________
>>> x3d-public mailing list
>>> x3d-public at web3d.org
>>> http://web3d.org/mailman/listinfo/x3d-public_web3d.org
>>
>>
>> --
>> *Leonard Daly*
>> 3D Systems & Cloud Consultant
>> X3D Co-Chair on Sabbatical
>> LA ACM SIGGRAPH Chair
>> President, Daly Realism -/Creating the Future/
>> _______________________________________________
>> x3d-public mailing list
>> x3d-public at web3d.org <mailto:x3d-public at web3d.org>
>> http://web3d.org/mailman/listinfo/x3d-public_web3d.org
>
>
>
> _______________________________________________
> x3d-public mailing list
> x3d-public at web3d.org
> http://web3d.org/mailman/listinfo/x3d-public_web3d.org


-- 
*Leonard Daly*
3D Systems & Cloud Consultant
X3D Co-Chair on Sabbatical
LA ACM SIGGRAPH Chair
President, Daly Realism - /Creating the Future/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://web3d.org/pipermail/x3d-public_web3d.org/attachments/20160126/67bbd47f/attachment-0001.html>