Does anyone have any experience in the software side of the industry to help explain why nothing open source is able to step up in a meaningful way?
There's no money in CAD by itself, meaning just the drawing part. Drafting is a low-value activity often performed by low-value workers who don't write software. Even if they wanted to, they couldn't make software tools for themselves. It's not like when web developers make web development tools, or when machinists make machinist tools.
CAD is sort of a piazza where the value a company gets from it comes from everything that's attached to it - reporting, CAE, CAM, etc. And they do invest in those things, often quite heavily.
It's big business to create these tools. The investment and expertise that go into them is enormous. That's why many of them cost as much as hiring another employee. They do at least as much work as one. They keep up with all the latest and greatest regulations, technologies, manufacturing processes, etc. And they give you access to a lot of valuable proprietary information.
Even if a company threw twice as much money at open source CAD, they'd still get basically none of that. They would just have an expensive drawing tool. It would be basically worthless and worth almost nobody's time.
For customers with low requirements, the less expensive tools do the job at just the right price point where it doesn't make sense to invest in advancing something like freecad.
Also, many companies in many countries are pretty much "allowed" to pirate the really expensive software. Once they get big enough, the software company will ask them to start paying some reduced amount. So there's an unofficial free tier that's way better than any open source toy.
Case in point, BRL-CAD has had more than 450 years of full-time effort invested, tens of millions with development spanning over four decades. However, that investment is heavily centered around features, integrations, and capabilities that are not as typically useful to the general public.
Usability's slowly expanded, but primary paid focus is military vulnerability and lethality analyses where BRL-CAD is absolutely unparalleled. Even against the likes of CATIA, Creo, NX, Solidworks, etc., development is heavily and strategically optimized and invested for solid geometric analysis, validity, verification, and performance. BRL-CAD so overwhelmingly outperforms the commercial tools in the analysis space and is so well-integrated that it would likely cost tens of millions to stop using it.
Still, general usability is not funded and is left to the auspices of the open source community. That's a long road. Adding usability and developing infrastructure for a system that complex takes time and a level of expertise that isn't common. Until it gets minimum viable general usability, it's hard to scratch one's own itch without personal investment or extrinsic incentives.
To me it sounds like professional CAD is really hard and nobody can "just make it" in a few years of work. That's the reason why open source CAD doesn't really exist today in the professional space. But once it exists, it will eat the world. The transition phase will still take dozens of years because of all the work invested in existing platforms. We will probably see something similar to the adoption of Linux in the commercial space where it simply makes sense to use Linux instead of developing your own OS or licensing some other OS.
The value as linkdink said above is the add-ons, integrations, extensions, and the like.
It's a bit like Unreal Engine 5 having integrated the Quixel model library. You don't just get some C++ code, you also get ready-made art assets. And then you get compatibility with four game console platforms, mobile platforms, etc...
Current Solvespace maintainer here. IMHO there is a lot that can readily be added to solvespace. Then there could be a big effort to do hierarchical sketches. And it is reasonably possible to rewrite some of the geometry internals if needed. All of these things are a LOT of work. The problem is the number of people with the background, software skills, and interest in contributing is very very small.
Having said that, we will just keep chugging along. I've been very busy with personal stuff this year, but soon should have free time to address my backlog of stuff I personally want to do.
Open Source has the advantage of time as long as people stay at it ;-) OTOH Blender and FreeCAD have used the constraint solver. If they borrow some of UI ideas then we all win too!
See: https://wiki.freecadweb.org/OpenCASCADE https://en.wikipedia.org/wiki/Open_Cascade_Technology
A pattern I've often seen is a tortise vs the hare sort of thing between FLOSS and $$$ software. The free stuff improves slowly but steadily. The $$$ stuff changes quickly but those changes are often driven by perverse incentives (people looking for promotions, shareholder value, etc.), and development tends to go off the rails and piss off users.
eventually i had to get a "real job", a job where i can't really be doing domain specific open source stuff without a potential conflict of interest.
on the plus side, i just bought a couch without having to worry about whether i can eat dinner.
https://mirrors.sarata.com/non-gnu/tovero/Tovero_tutorial.pd...
We used it for a few small projects. BRL-CAD also has Tcl scripting.
We've currently switched to pure Common Lisp and F-rep modeling for scripted CAD. This is the old CL one (again wrapped C++) we are porting:
Looks like the code is at http://svn.savannah.gnu.org/viewvc/tovero/trunk/ ? That's some impressive work, particularly some of the advanced geometry entity mapping going on in there.
"My kingdom for a voice" [1] or maybe "My kingdom for a horse" [2] we did post an item about it on the BRL-CAD mailing list. The Common Lisp community didn't really notice Tovero 2.0 for Common Lisp either.
I was actually thinking about trying a Common Lisp wrapper of BRL-CAD, or maybe doing a native CL port.
[1] REM, Document, "King of Birds", 1987 (Anybody know a good marketer?)
[2] Shakespeare, Richard III, Act 5 Scene 4 (a Tovero is a type of horse)
After I got it running I had some trouble getting it to do things and wrote to the email address asking for example files. Mike Muuss himself wrote back with a bunch of demo files attached.
That's kind of awesome. I built it from source a few years after that and didn't have to deal with any headaches at all.
BRL-CAD is one of the few "full-fledged" CAD systems that I know of which is explicitly CSG, while most (all?) commercial CAD programs are B-REP in nature.
CSG and B-REP are two worlds apart. I'm not sure why in the comments we're suggesting alternatives in the two categories interchangeably. They're not [*].
An alternative to BRL-CAD would be OpenSCAD or libfive studio + other tools (since BRL-CAD does a ton more) and more recently CadQuery. Maaaaybe Tinkercad could be classified as CSG?
CSG makes some operations easy at the expense of other things that become incredibly hard. The same is true for B-REP. Doing gears, highly procedural or FEM-directed models via CSG? Easy-peasy. But try to add a filled between two edges. Step it up 50 notches to fillet one edge and do the equivalent of "tangent propagation". Now the same, but also try projecting a structure on that round face.
CSG's speed is also wildly overblown. While B-REP is not exactly lightweight, computation complexity scales with the complexity of the model but can be sped up by caching intermediate representations.
In CSG this is not always true, since caching the intermediate representation can destroy the accuracy of the final mesh in ways which are very difficult to compute. So even for apparently easy models, times spend walking the space to remesh your model can grow _very_ quickly, hampering the ability to iterate quickly and experiment.
Not to mention, "measuring things" in CSG is hard. This is never mentioned, but none of the tools I've worked with so far offers convenient ways to examine and measure the objects you're working on. For a parametric model this is vital!
[*] Not saying there's no overlap. I'm using both systems. B-REP generally wins on a model which is feature-directed, which is why it's more popular. But I can relate to people that think that BRL-CAD is "hard".
CSG and hierarchical relationships still underpin, but a lot of effort was invested in BREP support over many years. There was already extensive support for polygonal BREP, but NURBS BREP was added to support seamless conversion of commercial CAD. BREP NURBS can be imported, ray traced, and facetized. BRL-CAD still needs direct surface editing, but you can mix implicit geometry with NURBS (e.g., subtract a hole) without issue. CSG entities can also be converted to BREP and work is ongoing to improve Boolean evaluation of BREP-on-BREP entities.
As for performance, implicit geometry with Booleans (i.e., "CSG") is typically an order of magnitude faster to evaluate (and an order of magnitude less memory than BREP/NURBS which is in turn an order of magnitude less memory than BREP/Poly). BREP/NURBS easily offer the most editing flexibility. CSG offers the most compression and programmability. BREP/Poly offers the most interop at the expense of representation fidelity, memory, and (sometimes) validity. All three can be "fast enough", but evaluation performance is still an important consideration on real/big models, e.g., fully detailed vehicles.
Note that generating an intermediate representation off CSG is not intrinsically necessary. When you have really fast+good solid ray tracing and analytic routines (and measuring tools) built around it, you don't need an intermediate rep. You just directly evaluate shotlines and get mathematically precise answers. That can be used for real-time geometry display, for measuring things, for identifying interferences, for computing properties, etc. That's BRL-CAD's primary niche specialty.
While I can't speak for BRL-CAD my experience with FreeCad which uses OpenCascade has been mixed. The chamfer/fillet tool there is just broken. If you use that and change some dimension it is likely to randomly crash. So, overall my experience has been ranging from rock solid to total trash depending on which features you use and what kind of models you create with it. The key question is "what do the developers use it for?" which should give you a hint for what kind of problem it is made.
Funny that. Working with Creo on a day-to-day basis makes me want to quit my job.
Wow.
The BRL of BRL-CAD is the Ballistic Research Laboratory:
https://en.wikipedia.org/wiki/Ballistic_Research_Laboratory
which developed, along with the Penn, the first general-purpose digital computer ENIAC:
