Polyhedral Splines
projects.blender.org
projects.blender.org
Wow, I remember this recurring extra-modeling-schemes conversation about Blender, and other FOSS mesh modelers from at least 2003...? Lol.
(In 2D land, Inkscape actually retains a few of these various convenient add-on vector drawing methods to this day)
The 3D modeling pitches were also always supported by CAD folks, who were looking to sideload about 10 tons of CAD kernel onto the latest parametric undertaking. Like, give us infinite modeling accuracy and resolution or give us death!
One issue here is this scrappy, Blender-style "whatever works in the final cut" Hollywood mindset [1] vs. the "can I recommend this, as a platform, to all of my friends" mindset in which all contingency needs must be covered, and so Blender is never, ever good enough for you, maybe. Or perhaps the "model itself must be exported directly to high-accuracy industrial plans" mindset.
The former is easier on FOSS teams. The latter always invites this "fork it" mentality and you sometimes get these temporary Frankensteinian spinoffs called "AutoBlenderCAD 3D", etc.
Also reminds me of JPatch? And some other third-party FOSS projects, RIP...
And: Cool if it turns into something great, even if for a while!
[0] https://fosstodon.org/@pafurijaz@mstdn.social/11071443700946...
I suspect it is a bit of hyperbole on the part of the original poster. as Blender has had NURBS surfaces since.. well forever. However nurbs surfaces are very difficult to use in a reasonable manner. As a workable alternative Blender has subdivision surfaces. which as far as the end user is concerned are splines that actually integrate well with mesh geometry.
That specific quote initially led me to dismiss the thread as someone jumping in without understanding blender at all. But I read the whole thread. And my personal conclusion(which does not matter a snot with regards to blender development) is that the original poster wants some poorly defined property that existing spline implementations don't provide(I suspect that if I were more familiar with splines this property would be obvious) and most importantly is willing to provide the dev time required to bring it to blender. So as a occasional blender user I welcome improvements to splines.
In regards to modeling workflow. Realistically, something like blender is good enough for most projects. but my heart lies with constraint based pad and pocket parametric cad. it fits the way I think better.
I fully intended to have a career in this stuff from age 13–20 or so. When it came down to it, the competition was insane and people were already willing to pay my good money to program, so… I took the path of last resistance :)
But AFAIK it will generate a variety of patch types (not just regular b-spline) to accurately represent extraordinary vertices and non-quad base faces.[1]
In general such representations are hard to manipulate. Stitching cubic patches ensuring C2 or C3 continuity is how we did organic modeling before the advent (or re-discovery, rather) of subdivision surfaces.
E.g. the dinosaurs in "Jurassic Park" were modeled from stitched NURBS patches.
[1] https://graphics.pixar.com/opensubdiv/docs/bfr_overview.html
Those were some fun times. I'd like to see that added into Blender some day.
Here is the only link googled.[0]
From the latest such apps look on Seamless3D.[1]
[0] https://cs.gmu.edu/~jchen/graphics/book/tools/softy3d.htm