Maybe because OpenGL and other libraries dropped them after v3.0 and didn't support, however, still other possibilities
It seems that we should build a "tiny" FreeCAD :)
If I remember correctly Blender does not support solids by design. The mesh modelling approach was developed as a fast method to allow artists maximum flexibility with animation. I ll try and find an earlier text by Ton explaining this.
@stephen_l B-Splines and NURBS are mathematical equations in this way:
Volume: V(u, v, w)
Surface: S(u, v)
Curve: C(u)
So, does Blender save and let us import and export them in those ways (parametrically)?
And for sure for representation, it evaluates them to meshes through tessellation or voxelization or other techniques
Yes blender does save nurbs in parametric way, but the current lib behind nurbs is quite limited, and not talking about missing required basic operators toolset.
So in order to get anything usefull, it probably will be way easyer to implement eevee/cycles into a nurbs / volume capable piece of software.
Blender uses the open source library OpenSubdivision started by Pixar. Besides of traditional poly meshes, this lib also supports SubD surface descriptions. I point this out, because surfaces described this way are much more efficient in storage, rendering and modern GPUs are / will be capable of real time presenting them.
But for now most workflows in Blender tend to convert all intermediate results to traditional polyMeshes of various tesselation levels.
I'm curious as well about the post of Ton, you mentioned.
@pixelpartner it seems that until Blender 2.92 they will improve their mesh system and include Vulkan, ...
Mesh is mesh, it's great for many usages, but not always, especially when it comes to volumetric data
Comments
https://github.com/blender/blender/search?q=quaternion
https://github.com/blender/blender/search?q=nurb
https://github.com/blender/blender/search?q=nurbs
https://github.com/blender/blender/search?q=spline
https://github.com/blender/blender/search?q=bspline
https://github.com/blender/blender/search?q=bezier
https://github.com/blender/blender/search?q=curve
https://github.com/blender/blender/search?q=knot
https://github.com/blender/blender/search?q=subd
https://github.com/blender/blender/search?q=subdiv
https://github.com/blender/blender/search?q=cube
https://github.com/blender/blender/search?q=cuboid
https://github.com/blender/blender/search?q=pyramid
https://github.com/blender/blender/search?q=prism
https://github.com/blender/blender/search?q=polyhedron
https://github.com/blender/blender/search?q=cylinder
https://github.com/blender/blender/search?q=cone
https://github.com/blender/blender/search?q=truncated+cone
https://github.com/blender/blender/search?q=ball
https://github.com/blender/blender/search?q=sphere
https://github.com/blender/blender/search?q=csg
https://github.com/blender/blender/search?q=sweep
https://github.com/blender/blender/search?q=profile
https://github.com/blender/blender/search?q=extrude
https://github.com/blender/blender/search?q=isocurve
https://github.com/blender/blender/search?q=isosurface
https://github.com/blender/blender/search?q=polynomial
https://github.com/blender/blender/search?q=brep
https://github.com/blender/blender/search?q=frep
https://github.com/blender/blender/search?q=voxel
https://github.com/blender/blender/search?q=volumetric
@stephen_l @Andyrexic could you please list all the obstacles related to Blender's geometry kernel? Solids, B-Splines (R2 --> R3, R3 --> R2), and NURBS?
It seems that Blender somewhat supports NURBS and B-Splines, but does it convert them to meshes?
https://docs.blender.org/manual/en/latest/modeling/surfaces/introduction.html
2-5 billion $ i guess.
Nurbs / B-splines display always is a mesh / curve evaluation.
Maybe because OpenGL and other libraries dropped them after v3.0 and didn't support, however, still other possibilities
It seems that we should build a "tiny" FreeCAD :)
If I remember correctly Blender does not support solids by design. The mesh modelling approach was developed as a fast method to allow artists maximum flexibility with animation. I ll try and find an earlier text by Ton explaining this.
@stephen_l B-Splines and NURBS are mathematical equations in this way:
So, does Blender save and let us import and export them in those ways (parametrically)?
And for sure for representation, it evaluates them to meshes through tessellation or voxelization or other techniques
Yes blender does save nurbs in parametric way, but the current lib behind nurbs is quite limited, and not talking about missing required basic operators toolset.
So in order to get anything usefull, it probably will be way easyer to implement eevee/cycles into a nurbs / volume capable piece of software.
Blender uses the open source library OpenSubdivision started by Pixar. Besides of traditional poly meshes, this lib also supports SubD surface descriptions. I point this out, because surfaces described this way are much more efficient in storage, rendering and modern GPUs are / will be capable of real time presenting them.
But for now most workflows in Blender tend to convert all intermediate results to traditional polyMeshes of various tesselation levels.
I'm curious as well about the post of Ton, you mentioned.
@pixelpartner it seems that until Blender 2.92 they will improve their mesh system and include Vulkan, ...
Mesh is mesh, it's great for many usages, but not always, especially when it comes to volumetric data
IFC NURBS samples: https://github.com/buildingSMART/Sample-Test-Files/tree/master/IFC 4.0/NURBS
https://github.com/buildingSMART/NextGen-IFC/issues/75