Our great sponsors
-
SurveyJS
Open-Source JSON Form Builder to Create Dynamic Forms Right in Your App. With SurveyJS form UI libraries, you can build and style forms in a fully-integrated drag & drop form builder, render them in your JS app, and store form submission data in any backend, inc. PHP, ASP.NET Core, and Node.js.
OCCT is definitely difficult.
I am almost as far as you can get from an expert but:
For example the TNP issue derives from OCCT (or something in the stack close to it, I am not exactly sure) not really handling face naming at all.
So if you want to avoid topological naming issues (which is a hard problem in CAD), you apparently have to do some work to track before and after and reconstruct your face naming.
https://wiki.freecad.org/Topological_naming_problem
https://forum.freecad.org/viewtopic.php?t=27278
Then there are various fairly entrenched issues to do with filleting and chamfering. Basically, both these operations will fail (in FreeCAD at least, but it's OCCT at "fault") if a chamfer or fillet would completely consume an existing edge. (It also sometimes creates impossible objects when filleting, or used to).
Booleans can be slow.
And more generally, it seems if you track the FreeCAD project that OCCT can be inscrutable when things fail; error messages aren't the greatest etc.
The flip side of OpenCascade is that it seems to be highly portable and has for example been compiled to JS with Emscripten for this astonishing thing:
https://zalo.github.io/CascadeStudio/
It's a monumental open source project, for sure, and it's definitely not nothing that we have an open source CAD kernel; these are projects that perhaps have to extend beyond the working life of an individual developer if they are to be stable. And there are loads of projects built around it.
Yes, absolutely.
It was where GIMP still is now, for artists.
It's definitely been idiosyncratic (if not solipsistic). And it still [0] has a core flaw that is being mitigated.
OpenSCAD is actually very limited in ways that don't become obvious until you get into a bRep CAD system at least. But it's how I also got into CAD.
If you like it, you might find Build123D [1] interesting: this is a Python (and very pythonic) environment built around the same kernel as FreeCAD.
I wanted to know there was at least something I'd be able to use for my own ideas, and the fact that OpenSCAD exists is definitely a blessing.
But I got from OpenSCAD to FreeCAD and I am very glad of it; it's an amazingly capable bit of software once you get past the pain (in the same way Blender is, I gather).
GIMP is not an amazingly capable bit of software for designers. It's broken and hobbled.
[0] the topological naming problem: being corrected in the core distribution at the moment as they head to 1.0
[1] https://github.com/gumyr/build123d