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Comment by conorbergin | Hacker News Reader

I could not imagine trying to design a 3d part without fillets. I use Build123d mostly, and have even gone as far as using the Open Cascade library directly, but if I had to choose between FreeCAD or OpenSCAD/Solvespace I would rather work around FreeCADs jank than give up fillets.

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Have you tried BOSL2? [1] Adds a lot to openscad, enough to keep me going at least. Fillets, chamfers, rounding, common parts, anchoring options, and it makes use of parent-child relationships between parts.

Not entirely perfect and some compromises, for example faceting isn't always consistent and hashtag highlighting doesn't seem quite right, but overall still it's good enough for me. The wiki on GitHub is pretty good, and with the source in hand I have had an easy time understanding what it does and tweaking it as needed.

For openscad itself, there are nightly builds with the new geometry engine, which too mostly works for me and is a huge speedup over the older CGAL engine. Renders that took minutes in CGAL now take seconds with the new engine. I like to take faceting through the roof for nicely rounded curves, but that kills CGAL apparently.

[1] https://github.com/BelfrySCAD/BOSL2

I see you still have to add a fudge number to stop the faces intersecting when doing a difference boolean. I'm afraid this is still strictly worse than Build123d or any other DSL than wraps OpenCascade.

Understandable, there are plugins and workarounds for fillets in OpenSCAD but they're not great.

If you're using Open Cascade through something other than FreeCAD, you may be having a better experience anyway. FreeCAD uses their own fork, which is hundreds of commits behind.

OpenSCAD is verbose, but fillets are just a cylinder subtracted from a rectangular prism.

Fillets in BREP software are so much more complex than this, your statement is a huge oversimplification.

I tried build123d with ocp vscode standalone and it seems interesting, but edit->run script->check browser-workflow feels annoyingly slow.

Maybe I'll try blender addon tomorrow.

I've been using it for a while and I honestly don't even check the output until I'm done sometimes. I think it's more important to make good preliminary sketches and have a good idea of what you want to make, checking the output every time you change a dimension isn't that useful.

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