fornjot VS sdf

I agree 100%.

Truck[1] and Fornjot[2] are recent attempts in the Rust space, both are WIP.

But both seem to be going the traditional way. I.e. B-Rep that can be converted to (trimmed) NURBS.

I think if one wanted to incorporate the last 50 years of computer science, particularly computer graphics, one needed to broaden the feature set considerably.

You need support for precision subdivision surface modeling with variable radius creases (either via reverse subdivision where you make sure the limit surface pass through given constraints or using an interpolating subivision scheme that but has the same perks as e.g. Catmull-Clark).

Then you need to have SDF modeling ofc.

Possibly point based representations. If only as inputs.

And traditional B-Rep.

Finally, the kernel should be able to go back and forth lossless between these representations wherever possible.

And everything must be node-based, like e.g. Houdini. Completely non-destructive.

[1] https://github.com/ricosjp/truck

[2] https://github.com/hannobraun/fornjot

Fornjot seems like this question was tailored for it: https://www.fornjot.app/

I think some interesting developments are made in that sector in the form of https://github.com/hannobraun/Fornjot and https://github.com/ricosjp/truck. Let's see whether one of those will actually get anywhere near a usable level. Fornjot in particular is shaping up really well.

E.g. Rhai[2] or Lua or whatever.

And I guess if their tech is solid enough, someone will do that eventually and open a PR or fork the project. They do not use an existing geomtry kernel but do everything from scratch which makes this a very interesting endeavour.

There also seems to be a goal overlap between Fornjot and DieselCAD

[1] https://github.com/hannobraun/Fornjot

[2] https://rhai.rs/

I have heard of yet another in-development CAD software like OpenSCAD or CADQuery, called Fornjot. Still, these are not ideal.

I'm not opposed to someone else adopting that code and creating that crate though! (Fair warning though, Fornjot might not end up using that crate. We might still go with another approach eventually.)

also it's to early to be off much use to you, but have you heard of https://www.fornjot.app/ ? it's a very in development cad kernel that is also aiming for integration into multiple host languages.

Yes! The website and repository README have a screenshot, and there are screenshots for each model in the models/ directory.

I'm kind of interested in this issue because it's what I immediately wanted when I ran fj-app.

I used to like OpenSCAD for its simple approach but then I discovered SDF-based modelling with Python made possible with this neat library: [1]. This is perfect if you are a programmer that doesn't know anything about CAD-Software.

1.: https://github.com/fogleman/sdf

>these the the central core that understands BREP and implements the geometric operations.

I've seen people quote a good modern CAD kernal as a 100 man year project. It's probably not going to happen, maybe there's some avenue for government funding?

Alternatively Signed-Distance-Functions are pretty nice. They're not BREP, but they're a lot easier to implement, and it might be possible to shove them into a BREP-shaped hole.

Here's a signed-distance-function based CAD kernal written in a few thousand lines of python+numpy, that seems to be about as fast as openscad. Maybe faster. https://github.com/fogleman/sdf

Excellent. You might be interested in a Python library that I wrote for generating 3D meshes (STL files) from SDFs : https://github.com/fogleman/sdf

It just uses marching cubes for triangulation but the SDFs are all numpy'd and the SDF is evaluated in batches on multiple threads so it's relatively fast.

I used the SDF repo by Michael Fogleman. Check out his website, there's a ton of useful stuff on there. He contributes a lot to the open source community and has been mentioned in r/PlotterArt before.

Try out fogleman/sdf[1]. It is like OpenSCAD in many ways but the distance field model gives you offsets and fillets more easily.

[1] https://github.com/fogleman/sdf

https://github.com/fogleman/sdf this python project can create mesh from sdf

> https://github.com/fogleman/sdf

Holy crap, why have I not seen this before?!?!!? I was even planning to start coding something like this myself. This is awesome!