alt Hacker NewsOpenSCAD is all triangles and vertices. Fillets are difficult to do. Outputting circles/spheres generally requires you to for-loop over vertices a lot.
Libraries like build123d and cadquery use OpenCASCADE, a boundary representation kernel. You think in terms of the enclosed solid and perform operations - boolean add/subtract, fillet/chamfer, stamp text, etc - that return a new solid.
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While true your argument is weak, for example in pov-ray the shapes are pure exact mathematical concepts. But nobody is saying how great this is for 3d printing or general cad work because it's not. The real key benefit from these programs is the interchange format they can generate, something you can feed to a machine, this prevents it from ending up like pov-ray, a terminal process only fit for generating pictures. Fillets are difficult to do in openscsd because fillets are difficult to do in general. What your argument probably should have been is that if openscad had chosen a geometry kernel where fillets were already solved it could then do fillets. Which is the sort of obvious tautology that helps no one.
Now I am off to see if anyone has ever built an export plugin for pov-sdl, either a 3d rasterizer(g-code slicer) for 3d printing, or a boundary layer mesh generator for import into another program. language wise it is probably equivalent to or better than the openscad sdl,
One subtle advantage to using python as the sdl is that it gets access to the vast corpus of python modules out there. Most of which are probably useless. but one thing I want to try is to see if I can use sympy to define a more declarative style of constraint.
I'm not sure I understand your comment; OpenSCAD has functions like sphere(), cylinder(), etc. Most OpenSCAD models I have seen are built up primarily from solid primitives combined using boolean operations, just as you describe for the other tools.
https://en.wikibooks.org/w/index.php?title=OpenSCAD_User_Man...