Someone in my moi3d AC group made this model with Plasicity, and everyone felt that moi3d modeling could not maintain G1 curvature and that the 5-sided polygon complement was inconvenient. Can anyone challenge this model with moi3d and attach a tutorial? I'm sending you screenshots and a Plasicity video for your reference. https://www.bilibili.com/video/BV1ZG411X7Nx/?buvid=XUFD92DFDB2D1ED4AD50B5FAA9C90C798DA22&from_spmid=default-value&is_sto ry_h5=false&mid=XAgPKRH86x4YDPG%2FmUAXuA%3D%3D&p=1&plat_id=116&share_from=ugc&share_medium=android&share_plat=android&sh are_session_id=df3ca26a-60a0-4301-a7b4-bee8232f0512&share_source=WEIXIN&share_tag=s_i&spmid=united.player-video-detail.0 .0×tamp=1699352329&unique_k=azjapws&up_id=479424569&share_source=weixin

Hi c3g, if you want to construct things by filling in patches between edges, Plasticity has a better patch construction command that it gets from Parasolid, so you can't really follow those same steps in MoI.

However, usually it's much better with NURBS modeling to form things like 5 sided boundaries by trimming an extended surface rather than trying to make a single surface that fits directly to the irregular boundary.

So in this case here that could look like this:

Initial profile curves:



Extrude:



Sweep:



Make a transition between 2 surfaces using Construct > Fillet:



Trim:



Trim:



So now the 5 sided region is formed:



The surface quality is much higher with this method because this area of the end result has a simple and well controlled surface shape:





If you look at the result of the patch method (is there a STEP version of the plasticity file available?), it's going to have awkward bunching in its shaping with a chaotic looking control point structure.

- Michael

My 2 cents to do it...



Pros and cons
It depends on the ability to make Filets which remains empirical for some cases.
But you have a single surface at the end if you use the process up to the version on the right
​

Thank you very much, this issue has been successfully resolved.By the way, your tutorial is very good to read

Another way for tests

Not the fastest
Not the most orthodox
Not my personal choice

But it exists...

Mesh and Subdiv...

Hi Michael,

Does ACIS have patch construction command as well? And could we expect to have it in MOI as well? or something similar?

Please notice: It is just a question out of my personal curiosity ( I have known your view on Patches; I think you generally suggest us to use polygonal modeling softwares for that matter! yet I felt the need to ask the above question merely out of curiosity! )

- Psygorn

Hi Psygorn,

re:
> Does ACIS have patch construction command as well?

Not in its base modeling library. It does have a separately licensed covering module but it's not that great.


> And could we expect to have it in MOI as well? or something similar?

Sorry no I'm not expecting to have that in MOI. If you need to do that kind of modeling, the best available patching is with Rhino using the XNURBS plugin or also Plasticity would be a good choice too.

Constructing things by patching between wireframe outlines is a pretty advanced and finicky area of NURBS modeling, it has a high learning curve and it's just not where it shines the brightest. MoI is more focused on modeling using 2D profile curves and booleans.

- Michael

Hi Michael,

Thank you for your explanation.

1- I do use Onshape when I need patching (although I am not very good at it but it worked for me)

2- I think we all know you had created Rhino so, I think there might be a chance that there are similarities between the two softwares (well I might be 100% wrong!) so, is there a chance someday someone could create a plugin similar to XNURBS for MOI? by studying XNURBS plugin structure?

3- Question number "2" is out of curiosity not out of necessity! :-)

- Psygorn

Hi Psygorn,

re:
> so, is there a chance someday someone could create a plugin similar to XNURBS for
> MOI? by studying XNURBS plugin structure?

It doesn't seem very likely, it's a pretty difficult area to make work well.

- Michael

@Psygorn

You can try to contact xNurbs guy directly too to show interest.

I don't want to paste the reply I get here, but to summarize : It's easy to do (would take a few weeks to prototype), 'they' would need Michael help. However they are concern with the community reception about the price, an other funky concerns about how to educate the correct usage of the product (?¿).

Also I think they don't support Mac, it's unlikely to happens.

Hi PaQ,

That's a good idea!

- Psygorn