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Libfive: Solid modeling (CAD) library/tools with Scheme/Python bindings and GUI

104 points| chuchana | 5 years ago |libfive.com | reply

38 comments

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[+] leoedin|5 years ago|reply
This is an area I'd love to see more development - but the existing tools I've used all have quite major drawbacks.

OpenSCAD is simple and relatively intuitive once you get your head around 3D space and how every object sits in it. The concept - code on the left, visualisation on the right is great. However, it's barely had any improvements in the 8 or so years I've been using it. The tooling is very basic and the performance can be very poor. There's often no way to know if a tiny change will crash (or slow down computation for so long it locks up) the environment (because it doesn't seem to have separation between the render thread and the GUI). Things like fillets, which other CAD environments can do seamlessly, are only possible with a hack which increases rendering time by many orders of magnitude (if it even finishes).

CadQuery seems promising, but in the time I spent with it I found the workplane model quite frustrating. I wanted to write small functional geometries which I could reuse again and again - but I didn't find an easy way to do that. It seems to use global coordinates for all the transformations, so you need to know ahead of time what plane something's on. Maybe I just didn't understand the documentation though - it's incomplete and so you have to piece things together based on examples.

These are of course open source tools, so it's great that they exist at all. In the age of 3D printing, laser cutting and CNC machining fully parametric code based model generation is really exciting.

[+] dTal|5 years ago|reply
There's ZenCad: https://mirmik.github.io/zencad/en/

I'm extremely impressed by what it tries to be, although I found it to be rather hit-and-miss stability-wise. Seems to be the work of a single gifted developer. I would love to see this tool mature because it's pretty much exactly what I want.

For programmatic mesh-based modeling - which is popular in the 3d-printing world but basically a non-starter for "real" CAD - Blender is starting to look quite promising. Blender's Python API is actually very nice for dealing with different coordinate systems (albeit a bit baroque when it comes to interacting with blender's knobs and buttons - although it's very discoverable thanks to the helpful API reference in the tooltips).

[+] mkeeter|5 years ago|reply
I'm the main author of libfive, happy to answer any questions.

The site isn't totally up to date – the Python bindings + API are brand new, and need some examples, but they work great if you know how to use them!

[+] leokeba|5 years ago|reply
Hello, thanks for your work, this seems very promising and I am very eager to push it a bit to see if it addresses the shortcomings of OpenSCAD, which I am using right now. However, when downloading the MacOS release of the Studio app and running it on my intel MBP, it seems that it cannot open the examples correctly. When opening the files with a text editor, I get the full content, but when opening them with Studio, only the last three lines (set-bounds, set-quality and set-resolution) are loaded into the text editor. I can copy and paste from my text editor and then it works like expected, but it's a bit tedious. Am I missing something or is this a bug ? I can open a ticket on github and provide more information if necessary. :)
[+] zyang|5 years ago|reply
I found it's really cool how you can prefix any variable with # and makes it interactivee. How do you map variables to draggable surface in studio?
[+] virtualritz|5 years ago|reply
I started working on some Rust bindings for this but I'm currently stuck here[0] with some bindgen issue.

If anyone wants to help that would be appreciated heaps.

[0] https://github.com/rust-lang/rust-bindgen/issues/2035

[+] iudqnolq|4 years ago|reply
I'd give cxx a shot. I've only written c bindings but I've heard great things about it.

> This library provides a safe mechanism for calling C++ code from Rust and Rust code from C++. It carves out a regime of commonality where Rust and C++ are semantically very similar and guides the programmer to express their language boundary effectively within this regime. CXX fills in the low level stuff so that you get a safe binding, preventing the pitfalls of doing a foreign function interface over unsafe C-style signatures.

https://cxx.rs/

If you're interested in chatting with a random inexperienced student about a month into writing his first Rust bindings I'd enjoy sharing approaches. I'm dzfranklin on the Rust language discord. (If you're not already aware of it the channel #black-magic is great for getting help with unsafe code)

[+] twarge|5 years ago|reply
While there are lots of similar efforts, the bidirectional interaction struck me as quit promising; you can apparently push/pull on features and have the Scheme code update.

There also seems to be an emphasis on correctness in the code, which sounds great to anyone who ever tried doing real work in FreeCad, though of course the gap in functionality is vast.

[+] dTal|5 years ago|reply
I actually don't know of many similar efforts. The only comparable project to this one is curv [0]

Coding shapes with signed distance fields is, unfortunately, highly impractical for CAD; operations tend to compose poorly (most operations a) assume euclidian space and b) distort space away from euclidian). But it's a pretty nice medium for generative art, and Scheme is a beautiful language to do it in.

[0] http://www.curv3d.org/

[+] andybak|5 years ago|reply
I'd love to make use of this in various open source projects but as far as I know the Mozilla Public Licence has the same problem as LGPL if you ever want to build for Android or iOS.

You can't mingle MPL/LGPL code with non-copyleft code unless it compiles to a separate binary.

And on iOS/Android - you're forced to have a single signed binary for distribution on the official stores.

Have I misunderstood? I would like to use it in conjunction with Apache licenced code. It feels like I'd be complying with the spirit but not the letter of the licence.

[+] mkeeter|5 years ago|reply
Check out Q8/9/10 in the MPL FAQ: https://www.mozilla.org/en-US/MPL/2.0/FAQ/

I don't believe the MPL requires the ability to re-link; this is one of the reasons I chose it over the LGPL.

(My intentions are to promote development of the libfive by require changes to the library itself to be shared, while not limiting commercial use / distribution / embedding into a larger application; there is at least one commercial CAD company using libfive as a component in their application)

[+] deckar01|5 years ago|reply
I tried ImplicitCAD for SDF modeling, but it was just as slow as OpenSCAD and the quality was worse. This looks promising.
[+] codehero|5 years ago|reply
Any reason why the first example (subtracted sphere) is rotating off axis or possibly has bad geometry?
[+] dTal|5 years ago|reply
How can a sphere be rotating "off axis"?