How does OpenSCAD type stuff play with simulation, in general. (If at all?)

I’m thinking of something like finite element analysis… but, I guess since the shapes in OpenSCAD are defined through this constructive geometry system, can things be better/more mathematically defined general purpose “discretize the PDEs over my mesh” type solutions?

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dranudin 3 hours ago | parent [-]

Normal finite elemts does not care. The mesh ist just put on your 3d body that can be an stl or a step or whatever. The FEM only knows the nodes and nothing else. The mesh geometry is completely separate from the CAD file.

Now there is a method called Isogeometric Analysis (IGA) that was meant to improve this. It uses NURBS functions (just like CAD) for the shape functions of traditional FEM. The idea was that now, if you have NURBS describing the CAD geometry you can skip meshing and just directly calculate on the real geometry. But it did not catch on. The reason being basically, as far as I remember, was that most CAD geometries of interest are not pure NURBS. But they are operations of NURBS (think cube minus some other cube - trimmed surfaces). And IGA has problems with that.

This is a problem that openSCAD will probably also not be able to overcome. Maybe at times it might be easier to create NURBS geometries without trimmed surfaces. But most probably that cannot be done in most cases of real world significance.

	▲	bee_rider 2 hours ago \| parent [-]
		Ah, that makes sense. I think Isogeometric Analysis was the idea I was circling (the though process being “of course you can always export to a mesh, but the OpenSCAD model seems to encode more designer intent so why not use that for simulations directly”). I’ll have to read up on what was tried and why it didn’t catch on. Thanks!