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Comment by beachy | Hacker News Reader

I feel CAD is one area where open source does not shine. The problem space is too complex, and the UIs demand continuous, thoughtful development driven from customer demands rather than developers scratching their own itches.

Not least there are free (as in beer) solutions available, like fusion 360, that are enormously capable.

Theres certainly a place for open source, and openscad would be a great tool to reach for for procedurally generated models. But in all honesty, Freecad doesn't compare well to the professional tools in this space - not in the way that say, gimp does to its commercial competitors.

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The real problem is that BREP CAD kernels are hard. A few of proprietary kernels dominate the scene: Parasolid powers NX, SolidWorks, Fusion, and Onshape, while ACIS (owned by Dassault) is used by Inventor and BricsCAD. Catia uses Dassault's own CGM kernel. The open-source world relies mostly on OpenCASCADE, which is unfortunately a lot less capable than any of these.

Fillets and chamfers are a good example. They seem simple but are geometrically non-trivial, and OCC will fail on cases that Parasolid handles without complaint. You can push either kernel to its limits if you try hard enough, but OCC hits that ceiling much sooner. So any CAD tool built on top of it inherits that ceiling too.

That's one of the real problems. The other real problem is an active resistance to UI improvement simply because another CAD package did something similar.

FreeCAD doesn't resist those comparisons anymore. They happen regularly. Implementing change is just slow, and purely copying how xyz cad built their UI isn't always compatible with FreeCAD, so a lot of careful consideration goes into things before concepts from other software get implemented. Not to mention that developers seem to really dislike doing frontend work.

Aaaaah! No! You're doing it too! I am not talking about copying how xyz cad built their UI. I am not talking about consciously implementing concepts from other software. I'm talking about this crazy tendency to assume that the reason someone wants UI feature X is because xyz cad does it, not because it's a natural, intuitive thing to want to do. Natural, intuitive things tend to get independently invented; more than once I've made a suggestion and had "this isn't Fusion 360, you know" thrown back at me, despite the fact I've never used F360 to know what comparison they're making.

I wasn't implying you were doing that. I don't play the 'this isn't fusion or xyz cad' argument when someone brings a suggestion. I'm only stating that not every idea will work properly in the context of FreeCAD, but comparisons are considered when such suggestions are made.

The thing you are complaining about is the immediate dismissal the forum used to shoot back at people with ideas. Most likely a conditioned (and very toxic) response from receiving a lot of equally non-constructive feedback using things like F360 as their litmus.

Either way, there is the Design Working Group which evaluates ideas and feedback with a fair lens about what will work in context of FreeCAD and what is feasible to implement without causing unnecessary disruption to existing users. It is a complex social paradox to deal with.

Do you think this is why CAD software UI/UX is often so clunky? The kernels are complicated and error-prone given the incalculable number of edge-cases, which puts error reporting at a disadvantage, leads to counter-intuitive feature wizards with some having way too many parameters and others being very single-purpose?

> Fillets and chamfers are a good example. They seem simple but are geometrically non-trivial, and OCC will fail on cases that Parasolid handles without complaint.

A long time ago I interviewed at one of the large CAD companies. I remember getting an office tour and the person showing me around pointed into a corner with six desks and said "that is the team that does fillets".

Open source tools can handle some cases, but to handle the full complexity of real world problems is a huge extra step that I doubt they will manage any time soon.

Were their desks shaped like this? https://www.staples.com/bush-business-furniture-cubix-48w-co...

> the UIs demand continuous, thoughtful development

The current AutoCAD GUI is essentially unchanged from the 80s, so this shouldn't really be much of an issue. They added a ribbon probably 15 years ago at this point, but I can't think of any other major/recent changes. (But maybe there are some changes that I'm not familiar with, since I don't use AutoCAD very often and only started using it relatively recently)

People aren't talking about AutoCAD, but things such as Autodesk Inventor, AD Fusion 360, ...

fusion 360 is exactly "free" for that reason, to make people reason like you do. They do not want a blender moment.

Note as a Linux user, the only version of Fusion you can really use is the (bad) browser one, which requires a $900/year subscription. I like Fusion, but this is a powerful motivator to make due with FreeCAD or Dune3D.

Fusion 360 and my golf sim software are the only two reasons I have windows dual boot.

I wonder if anyone has first-hand experience they can share with Fusion 360 under Wine.

It's incredibly rough and unreliable, sadly.

> I feel CAD is one area where open source does not shine.

Many such cases, not only in CAD area. Good non-dev FOSS software is exception, not a rule, and these exceptions pretty often have some corporate backing and are not purely community-driven. And even for dev tools there are proprietary offerings that are light-years ahead of anything FOSS, though people here are never going to admit it, as TTY clone running vi clone is supposedly all you need.

I don't state this with satisfaction, quite the opposite, but it is long since I became disillusioned.

The reason being that Open Source is a bunch of people who approach EVERYTHING as a programming problem, and they are chronically allergic to graphics, graphical UIs, and any kind of sense of what user interactions are a good experience.

They don't start with "how do users want this to operate?" They start with a weekend of coding, applying their preconceived notions, a library of fancy algorithms that are not directly motivated by an actual feature, and they go from there. This does not lead to a good product, as in something that could earn you money on an open market. It only prevails, in spite of nobody wanting to pay for it, because they give it away for free, and they sink their own "disposable time" (and maybe even income) into the project.

I'm use Vectorworks professionally, but that's because it's become the de-facto program for drawing in the entertainment / production space, and uses Parasolid. I'd love to have any, ANY alternative to VW and Nemetschek's awful pricing / subscription scheme, but I don't see FreeCAD being a competitor in this space for many, many years. Maybe for hobbyists, but I agree that the problem space is oversized for a community project like FreeCAD.

Another advantage of OpenSCAD (if you can call it that) is that LLMs seem to be able to work with it pretty well. A few days ago I asked chatgpt to make me a box for storing batteries, and it came out perfect on first try without any modification. It also made an okay-ish looking 3D pelican after some back-and-forth.

The problem with openSCAD is that you cannot modify it easily. I had made a complex geometry several years ago in openSCAD and I have been waiting for a model that can actually convert it into a python script that generates freecad parametric sketches that recreate it in an editable way. All frontier models fail at this, some more spectacularly than others (gemini never spent 40 minutes / $4 trying and failing, but opus 4.6 did).

https://www.thingiverse.com/thing:4335532

OpenSCAD is ideal for making models that can be modified! You have to program your models with the mindset of parametric CAD though, if I was making a battery case I would start by defining variables for battery length, diameter and count and work from there.

Your ball looks well parametrized to me, what kind of editing are you missing from it? Unless you want to change the shape of the locking mechanism altogether, which I think would be a chore in any format.

Yeah the lock is what needs iterating. It was always marginal and took several rounds of prototyping to even get to a printable state. I'd like to experiment with something like a keyed screw.

The issue with this scad file is that I built the geometry up with no functions. I tried and failed to get them working so I just pushed through, so now it is mind melting to try to refactor it. I'm hoping to one day melt a mechanical mind to get it done. Until then, it's a fun challenge prompt for these models.

Openscad models are a bit like complex regexps, write only artifacts that do the job at the time but are regarded with trepidation afterwards.

there are a lot of "do what I mean" type papercuts in openscad. BOSL2 is a library that, for me at least, takes away enough of them to make a rewarding experience. still find myself brute forcing which axis to translate or rotate things the way i want.

concur otherwise that openscad is parameter friendly. the lightbulb moment for me was when i finally grasped its functional grammar and leaned into it, esp recursion instead of algebraic solutions. that should probably be the subject of a tutorial or several.

I never understood this UI problem.

Because... You can copy the UI of the leader and problem solved.

There you have GIMP with an absolute nightmare UI to use, but people keep saying, just get used to it. On the other hand, a single developer, in javascript, made a copy of photoshop, and most people I know prefer to use that over GIMP...

Just copy the UI that works, if you can't research your own UI.

>Because... You can copy the UI of the leader and problem solved.

For whatever reason, the FreeCAD community is explicitly against taking note from competitors. Copying the UI of the leader is a thoughtcrime.

No it isn’t, stop being silly.

Why do you think GIMP is a nightmare? I don’t find it problematic at all. The only issue I’m hitting once in a while is that I click on a button on the toolbar, and I guess I hit its edge, as I doesn’t switch modes. Other than that, I don’t have any complaints at all. What are yours?

It's mostly a received holdover opinion from the days when Gimp still defaulted to being strongly multi-windowed. The people who keep repeating it probably haven't used Gimp for a while. The usability may still not match Photoshop, but at this point the Gimp UI is largely conventional for this genre of software.

Popular opinions take ages to shift sadly.

Yes, I learned on Paint Shop Pro and have used many image editors over the years. GIMP is very similar to the rest of them.

Adding a text that has a couple of pixel white borders is something possible in GIMP, yet a nightmare compared with photopea which just copy cs2 way of doing it.

And that is without having to edit the text in case you made a tipo.

Now, if we are talking about doing batch image editing in python. Gimp us the best tool I've found.

I use GIMP and FreeCAD quite often and find them very powerful programs, but maybe I'm some sort of genius? I think where these programs don't do well is among the crowd who expect to be able to just click around an advanced piece of software and somehow it just works to get things done! For basic apps this is a reasonable expectation, but CAD is not a simple process.

PS: I've still not managed to learn Blender, not put enough hours in, it is a hugely complex beast of a program that basically requires keyboard shortcut use imho. That interface (beautiful as it is) has so many options that even if I know what I'm looking for I can't find it!

Yeah, to use these UIs you gotta think like a programmer.

Part of what made Blender accessible around 2001-2002 when I was using it regularly was a really great paperback book[1] that served as a tutorial and reference. The UX was strange to be sure but after reading through the ~200 pages and getting acclimatized, it all began to feel sensible. If not for that book I would have bounced off Blender and never looked back.

[1] https://www.abebooks.com/Blender-Book-Carsten-Wartmann-Starc...

Do you mean photopea?

Great alternative in-browser.

I do, it is indeed. I'm always surprised that a single developer in javascript managed to do it.

Same. When I first saw it, I couldn't believe that was possible in the browser.

It makes me want to investigate that style of application.

I think it even works offline.

> There you have GIMP with an absolute nightmare UI to use, but people keep saying, just get used to it.

Which is something I find odd that so many people seem to assume GIMP as the de-facto open source photoshop alternative when Krita is more analogous and much easier to use.

What's the name of said copy? Would gladly test it because I have a hard time with Linux right now due to not being able to just use Photoshop. Currently trying Krita and it's alright, because GIMP is just unusable.

https://www.photopea.com/

I don’t know, I tried FreeCAD a few months ago and it was buggy as hell. I did some really basic extrusions and distance constraints. But ended up with non-perpendicular entities despite not constructing it like this.

I assure you that my 3d prints look like what I designed them.

I've been using FreeCAD for around 5 years no, and I can't ever recall running into such a problem, ever. I first started learning it during version 0.19 at the end of 2020 after years with solidworks and onshape. The user experience just sucked royally, it's far better today than back then.

Image manipulation doesn't shine either. GIMP is the prime example.

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