Full Version: XNurbs for MoI

Hello Moiers!

I had a conversation with the XNurbs developers some time ago, and while there are a few concerns, there's also some positive feedback. I won't share private messages, but to summarize:

* The XNurbs team is interested in creating a plugin for MoI.
* However, this would require development time from Michael, and I'm not sure if he's willing to invest the effort. Michael has a clear vision for MoI, and XNurbs is definitely a niche feature.
* Pricing is another consideration. I don't think it's reasonable to charge twice the price of a MoI license for a plugin, so there needs to be some middle ground on this.

I've been using XNurbs in Plasticity for a while now, and it's an impressive tool. It offers surfacing options with continuity features that I often find lacking in MoI's current toolkit. I understand that for surfacing purists, XNurbs might be seen as unconventional, but for my use case—creating game assets and rendering geometry—it's a perfect fit.

The main reason I believe XNurbs would be a great addition to MoI is the lack of continuity options in its existing tools, aside from edge-to-edge blends. Despite the goodwill, I find Plasticity's UI, geometry manipulation, outliner, lack of quad views, shortcut combos frustrating.

Personally, I'd be willing to pay an extra $200-300 for access to this surfacing tool within MoI. I'd love to hear your thoughts on this, and maybe we can use this thread to gauge interest from the community.

Cheers.

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Had a request years ago for muti sided blend and blend parameter access tools. I think the current geometry kernel is the limiting factor for Michael (well, the time investment also)

Looked at xburbs in the past

I would choke up 200-300 to add it to my MoI

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Probably the way with the least amount of work overall would be that I'd do all the XNurbs/MOI integration work myself (because it's a lot of work to make a full C++ SDK, I can make a specialized one with just what is needed for XNurbs a lot more easily) but the resulting plug-in would be sold and distributed only by the XNurbs team as they do with Rhino and SolidWorks plug-ins currently.

That way there doesn't have to be any IP licensing set up which greatly simplifies things.

For timing probably near the start of the MOI v6 cycle would work because I'm heavily occupied with ACIS integration work for trying to wrap up v5.

Thanks, - Michael

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Hello,
Excellent idea! Thanks PaQ!
I'll buy the plugin.
Thanks Michael for the interest.

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@Michael,

I'm sure this is a really dumb question, but is it not viable for you to create your own xnurbs instead of relying on a third party?
-B

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Hi Billabong,

re:
> I'm sure this is a really dumb question, but is it not viable for you to create
> your own xnurbs instead of relying on a third party?

It could be possible but that type of surface fitting is a finicky area of work. It tends to be difficult to avoid oscillations.

It's hard to accurately estimate how much work would be involved, my initial guess is maybe 5 to 10 years?

- Michael

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well that pretty much cancels that idea, LOL

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Hi Michael,

I would like to know your anticipation on how far would it be? - in terms of years-

-Psygorn

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Hi Psygorn, probably sometime next year. But that depends on whether that approach is accepted by XNurbs, I have not discussed it directly with them as of yet.

- Michael

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got it :-)

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That's really encouraging, thanks for your input Michael !

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It's really nice to see some new surfacing tools, either x-nurbs plugin or implementing ACIS kernel into network and n-sided commands to add more features to them.
While it is not completely related to the x-nurbs discussion, I was thinking, Is it possible to make a plugin to connect moi to freecad library to use its surface filling tool inside moi?

I know it's not as powerful as x-nurbs, But, It has these features:
Making a surface with boundary curves/edges
Accepting guide curves/points
G1/G2 continuity

https://wiki.freecad.org/Surface_Filling

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Hi Mo, that could be a possibility but I haven't heard much about how well it behaves.

Have you used this function in FreeCAD very much?

- Michael

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Hi Michael
Actually, I haven't used it that much except for a couple simple surfaces. But here is a test for more complex situations.
To be fair, I tried to use these videos as reference to compare freecad and x-nurbs results. ( I just quickly glanced at the curves in the videos, so it's not exactly the same. )
https://www.youtube.com/watch?v=mGbYDIqt_MM
https://www.youtube.com/watch?v=a1Himxz1C-Q

As already known, using freecad's surface filling tool was challenging. You can't just select all the boundaries at once and get the x-nurbs magical results.
I tried to minimize the patch area to make it simpler for freecad. You can see the results in the attached file.

Results are not perfect for sure and I totally understand if you don't want to put your time on it. :)

Attachments:
Freecad_surfaceFillingTool.zip

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Hi Mo, thanks for the tests of the Freecad surface filling module.

But yeah it does not look promising, it looks like it is afflicted by oscillations which is often a complication with this type of surface fitting calculation.

You can see them particularly in this surface:







The control points kind of wildly spike back and forth to opposite sides of the surface in a small area. This makes the surface have a kind of subtle bumpy shaping to it in those spots.

Some of the other surfaces in there are not so bad as this one but it does not really bode well for being very reliable.

There are kind of opposing forces between maintaining surface smoothness versus accuracy of forcing the surface to pass through curves. It is quite tricky to balance between these.

There will often be either oscillations or inaccurate results that aren't close enough to join up with the existing edges. Or both.

- Michael

Image Attachments:
freecad_filling1.png  freecad_filling2.png  freecad_filling3.png 

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If so, make cars will be more easy here.
You could recover all users that migrate to Plasticity because of Xnurbs.

M

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