I made my first request in 2003, since then several projects have passed, the fact that Ton is not interested is not true, there have been several attempts, and none has ever reached a level that would make possible what is today done with SP, it is possible because Blender has already introduced several new improvements, having said that we are all aware that Blender aspires to become a visual effects player, which is what Blender was born for, but several independent projects were born around the project such as BlenderBIM, each of these has different uses, I have been using it as CAD for years and I try to promote this type of use, Ton has said several times that there are other projects that are more suitable for making CAD, only recently has a glimmer of opportunity opened up in world of design and this is due to the subdivision surfaces certainly not to the Nurbs functionality.
We talk about money because you talk about it!
And I repeat, I am happy to contribute, however, we must first understand what can be done with it, and what its real capabilities are otherwise as has happened in the past where fundraising was done and time and enthusiasm was spent on projects that ended up in a dead end, such as also for Blender Nurbs https://archive.blender.org/wiki/2015/index.php/User:Jjoonathan/NURBS_Final_Report/
I am not blaming Ton - under his hand and the team Blender matured perfectly in some areas - just not NURBS.
also for mesh modeling Blender could use some big help - compare this to Hexagon 2.5.
but anyway I agree with you
Oh I was looking for Jjoonathanās work and never found it, thanks !
And yes, one of my main preoccupation was on ways to not repeat the past failed attempts. And for me GN was quite a good options because, it should update with Blender, and your SP files will 100% work without the addon. And even if it breaks, and for some reason Iām not here anymore, in theory it is quite simpler to dive into the nodes than into my badly written code. Mainly because nodes impose me a structure, whereas code will give me too much freedom and encourage me to do noob hacks and messy stuff.
Separate from the recent conversation aboveā¦
I recently gave SP a go along with your test files and found it to be a refreshingly new approach to nurbs surface development. Although I donāt fully understand the intricacies of each function youāve put together, I was able to fumble through it and connect some patches with various levels of continuity.
Keep up the great work! I look forward to what will be possible. Iāll be keeping my eyes 
on you!
Also on the topic, if Blender ever wants to involve me in the making of a new NURBS datablock, I would be honored and certainly agree. I saw the question being asked somewhere, since the new curve datablock needs to have a NURBS subtype like the old one. There is a world where, like simulation nodes, the core devs make the basic blocks and the community builds onto it all the tools with GN asset packs.
Thanks, I agree this is not very understandable for the moment, and I donāt do to much doc also because it is still changing quite a lot. For example no more āBezier Chain / Any Order Patchā difference in alpha 5, this is legacy from when I needed to quickly prove the concept.
Comments above didnāt understand you were offering 50 Euro as a reward for an algorithm to rearrange the grid index to integrate it into Surface Psycho and not asking 50 Euro donations for your work.
Just clarifying in case anyone that can do that kind of work reads this and feels tempted to contribute.
Also the project already attracted a 100 times my expectations so I could never complain. Before SP, I spent all my free time making art with no audience and I will probably continue. And when I started SP I was terrified it wouldnāt be noticed, which is clearly not the case.
Btw @RomainGuimbal I think your approach is great and will certainly be useful. More than a few times Iāve found myself wanting to loft meshes directly on blender for character design or quick adjustments around props without opening other software for convenience, ease of use, visualization, testing materials and integrate them directly ionto other processes Iāve developed myself inside of blender.
And of course it can be done, thereās many solutions available, but I have to say that the problem you are trying to solve is something Iāve come to need many times before.
Funny that you mentioned the grid sorting. For a while Iāve used a few node presets with loft and sometimes they flip around randomly depending on the angle, they look just like the example you posted with the grid index, but with meshes and curves, with the subdivisions, the weird continuity, and some addons use collections and break when things move around, is just annoying.
Sometimes when you are dealing with several minutes of animation with a bunch of assets and simulations the last thing you want to do is to open Rhino. Seeing the curves move and create those continuous patches on the fly for blender is huge, at least for me.
So I think you are definitely on the right path, you had your eureka moment and you know this has a lot of potential so I know you donāt need to read any of this stuff.
But just in case.
Thank you, it meansa lot to me. I love how since Blender is so open, if I do a tool for a very specific need, it ends up in the hands of people who immediately knows how to use it on a very different task. I donāt think people from commercial softwares realize the magic of this
Iām working on more important stuff too, but they are not ready, so take this 
Fillet Bezier patches !
This required a whole upgrade of the matrix inversion for better numerical stability, and it isnāt even sufficient. Anyway, the next step is radius control per corner.
Also Iām working on the importer and it fails to iterate through the shapes for some reasons 
Fillet per corner !
Looking at this, the obvious missing feature here is hole support, not sure how hard it could be
There is matrix attribute data type in 4.2.
Yes but it is only for transform matrices, the homogeneous coordinates which are 4*4 matrices. Maybe grids will have an invert matrix node but not for the moment if I didnāt miss anything
Transform matrices are 4x4 and now have nodes to acces its raw components.
Yes, and what I made is a n*n matrix inverter
First, I want to express my gratitude.
I happened to become captivated by the CC850 Hypercar and did some modeling and rendering related to it. Among the related videos, this addon was introduced, and when I looked into it, I was very surprised that it is FREE.
I also found the development process very interesting and read the comments.
I tend to avoid using addons, but this addon seems to be a fantastic way to implement surfaces as NURBS in Blender, so I want to give it a try.
It is indeed true that the current version of Blender is somewhat limited in representing surfaces.
Iām grateful that your talent has brought me joy, and I believe others will also be thankful to you in the future.
Later, Iāll treat you to a cup of coffee for our conversation (figuratively speaking).
Take care of your health and pace yourself. 
Thank you !
It is free for a lot of reasons, but one of them is to receive more comments from enthusiastic people 
Circles and disks are now of any order and any segment number !
hi there, big kudos and thanks for the effort. I always believed that Blender will become somewhat NURBS capable at some point. I briefly scrolled through this thread and checked some vids, images and it looks impressive, but I am not sure why I would not simply do this in Moi3D, Plasticity or even Alias.
My background is Automotive Design, so I started in Alias, but currently use mainly Blender, since I usually just need to visualize my ideas. If I need NURBS precision I can import Sub-D into Moi3D. I got used to SubD, but I really miss creating surfaces from curves and trimming/blending them. It seems like Plasticity is getting close to this with xNurbs. Alias is of course on a different level, but it can even combine SubD and NURBS surfacing. Most Automotive designers have some Alias knowledge, it is usually taught in Design Schools, so many designers would like to build 3D models in an Alias way, but in Blender.
I highly agree with pafurijaz, there should be some very straight forward examples of how to use SP (btw I like the name surfacepsycho) in a similar way like Alias/Plasticity/etc.
For example, one very important criteria would be the ability to create 4 sided patches with all G3 continuity. This simple demonstration would make a huge difference.
And good, fast Fillets of course.
I have not installed SP yet. I would like to look into it, but time is limited and I still have to try out Plasticity. And learning new software is always a painā¦
So maybe I am a good example of a potential customer. (I believe you have to put a price on it eventually to be able to maintain the development, which is fine for me)
Anyways, keep it up. I will check the add on at some point and will give you feedback (from the perspective of an Automotive designer who has no clue about coding and barely any knowledge of GN. However I know what complex, high quality surfaces look like and how to build them.)
Best regards, k526