Freecad for users of Blender

A place to share learning material: written tutorials, videos, etc.
Forum rules
Be nice to others! Respect the FreeCAD code of conduct!
vocx
Veteran
Posts: 5197
Joined: Thu Oct 18, 2018 9:18 pm

Re: Freecad for users of Blender

Post by vocx »

Celica_Supra wrote: Thu Feb 28, 2019 5:05 pm I totally agree with Openbrain, FreeCAD is engineering oriented and Blender is artistic. I am not experienced on the modeling side of blender. Freecad is a parametric modeler where every modeled feature is able to be defined by hard dimensioning, has a history tree etc whereas in my limited experience with Blender, it has more of a direct modeling approach which makes organic surfacing WAYY easier, but doesn't have the hard dimensioning/sketching/history tree available. I think the core of this conversation is trying to translate understanding between direct modeling and parametric modeling.
...
Kunda1 wrote: Thu Feb 28, 2019 6:05 pm It would be super cool to have some sort of tutorial that translates blender-speak in to FreeCAD-speak.
Or How do I do this in FreeCAD if I'm a blender user type of thing.
I think this sort of tutorial would have to be very basic, because as other users have explained, the two pieces of software have different underlying philosophies. Blender is a tool to model objects by editing meshes, meaning directly moving the nodes that form a quadrilateral or triangular surface. Meanwhile, FreeCAD is a tool to model objects by precisely describing the relationships (parameters) between primitives (wires, sketches), and their derived features (extrusions, pads, fillets, holes). So the two approaches are fundamentally different.

If you want to precisely define the dimensions of an object, for example, for manufacturing, it makes little sense to use Blender. And if you want an organic object or character, with many fine details that can't be described mathematically very well, it makes little sense to use FreeCAD. Blender stores the meshes (clouds of points), while FreeCAD stores mathematical relationships. In any sort of tutorial, this distinction should be clearly explained, so the user doesn't try the wrong approach in the other software. And yes, of course one approach makes more sense for artists (Blender), and the other for engineers (FreeCAD). Artists generally build (draw, sculpt) something just by looking at proportions (the head should be proportionally smaller than the torso), while engineers need specific information (lengths, angles, tolerances) for precise manufacturing.

FreeCAD can import meshes, and it can create basic meshes using the Mesh Workbench, but it doesn't have tools to easily edit individual nodes. Without having looked at the code, I feel it should be easier to embed the core mesh editing components of Blender into FreeCAD, than it would be in the other direction, that is, to embed a parametric modeller (OCCT) insider Blender.

Imagine this in FreeCAD: creating a mesh primitive (Blender's starting cube, plane, torus), subdividing it many times to add more points to the mesh, and then moving the individual points (Blender's grab [G] command). That would be enough functionality in FreeCAD. You don't need modifiers, texturing, lighting, key frames, animation, light paths calculations, shadows calculations, etc. The only thing that would be needed in FreeCAD would be a simple mesh editor to move points, edges and faces around (maybe with a gizmo like Blender does), and a subdivision surface operation. That would be useful to import a mesh from somewhere else, maybe Blender itself, then edit it slightly in FreeCAD, and optionally turn it into a solid body, in order to use this solid in further solid operations (Boolean additions and cuts). This solidifying of a mesh already exists in the Part Workbench, with Part ShapeFromMesh and Part ConvertToSolid, but I think it's not very well known.

Edit: after reading my own post, I feel the "tutorial" that people want basically consists of the first two paragraphs that I wrote above. In my opinion, the FreeCAD documentation should explain this difference very prominently, as other than Blender's extrude and FreeCAD Sketch+Pad, there won't be a direct translation for most Blender operations.
Always add the important information to your posts if you need help. Also see Tutorials and Video tutorials.
To support the documentation effort, and code development, your donation is appreciated: liberapay.com/FreeCAD.
gonestefan
Posts: 2
Joined: Mon Jun 24, 2019 3:53 am

Re: Freecad for users of Blender

Post by gonestefan »

It is true that Blender is used extensively for "artistic" type modelling, rendering etc, but some people have also done amazing high precision engineering modelling.
For example look at some of the tutorials on this site http://rab3d.com/tut_blender.php.

There is also quite a strong group who use Blender for purely architectural design work -
https://www.blender3darchitect.com
https://www.blendernetwork.org/matthieu ... e-dinechin
not to mention our own Yorik - https://yorik.uncreated.net/?blog/2016-289

It's not that common, but Blender certainly can be used for "hard" modelling projects!
So some sort of Blender - Freecad cross-over discussion is a great idea, I think
Post Reply