[x3d-public] Extrusions, take 3

Tue Jan 26 17:54:10 PST 2016

I think if we restrict Extrusions in V4+ to 2 spline points, that would work for me too.  An easy fallback for V4 products to support V3 might be to ignore all points in the spline except for endpoints.

I think that when SVG is incorporated, if it is, then Extrusions from SVG (meta-SVG?) will become important, so we may want to keep Extrusions around.

John

> On Jan 26, 2016, at 8:21 PM, John Carlson <yottzumm at gmail.com> wrote:
> 
> All I would really like to see is an easy way to define Cylinder with 2 endpoints and a radius.  If that is provided, I have no problem with deprecating Extrusion from the standard.
> I do not think defining a Cylinder in this way would be onerous to a run-time, but I could be wrong.  If someone could provide an example of a Cylinder like this, it would be great!
> 
> John
>> On Jan 26, 2016, at 8:13 PM, John Carlson <yottzumm at gmail.com> wrote:
>> 
>> Uh, I asked for an IndexedFaceSet.  Thanks, though.
>> 
>> John
>>> On Jan 26, 2016, at 8:11 PM, doug sanden <highaspirations at hotmail.com> wrote:
>>> 
>>> 
>>> http://dug9.users.sourceforge.net/web3d/tests/41.x3d
>>> 
>>> snake animation animating extrusion spine
>>> 
>>> From: x3d-public [x3d-public-bounces at web3d.org] on behalf of John Carlson [yottzumm at gmail.com]
>>> Sent: January 26, 2016 6:04 PM
>>> To: Leonard Daly
>>> Cc: x3d-public at web3d.org
>>> Subject: Re: [x3d-public] Extrusions, take 3
>>> 
>>> Maybe just show an example of an IndexedFaceSet which is an extrusion of a circle with 3 spline points, with the “bend” animated from 90 to 180 degrees.
>>> 
>>> It’s okay to use Blender or Maya, I’d just like to see what the results look like.
>>> 
>>> John
>>> On Jan 26, 2016, at 8:01 PM, John Carlson <yottzumm at gmail.com<mailto:yottzumm at gmail.com>> wrote:
>>> 
>>> So how do you propose to animate IndexedFaceSets in a declarative or VRMLscript or JavaScript manner if they are Extrusions?  Can we see an example?  If the developer has to do it, can we help them?
>>> 
>>> John
>>> On Jan 26, 2016, at 6:58 PM, Leonard Daly <Leonard.Daly at realism.com<mailto:Leonard.Daly at realism.com>> wrote:
>>> 
>>> 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 <<mailto:Leonard.Daly at realism.com>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<mailto: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<mailto: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
>> 
> 