CAD Scripting
I first learned about this in my FEA course, where we paramaterized the model by looking at the script that generated the design/FEA models.
Then in fluids, there was a bonus assignement to model fluid flow via solving partial differentiial equations (PDEs) and I was the only one in the class to solve it :). At the same time, I took a graduate CFD (computational fluid dynamics course) and started doing finite difference methods to solve these PDE's and show the models.
I moved into robotics/ML after this because I found it more applicable to my future :).
Recently, in 2024, I started relooking into simply making designs via code. I got lost in the weeds with learning the methods so just got to using the software now (end of 2025).
However, I don't really know if the scripting to generate code is super useful in prototyping... I haven't used fillets yet, but someone online talked about how it's hard to select an edge. And I was using figma to design my gamenight business cards today and could see how I would code it, but could see how it distracts from "design iterations" that you normally get with a gUI.
Anyways we'll see how I far I go with this scripting CAD. I kinda like the idea of an LLM to generate CAD scripts, so might start delving into that aspect shortly.
Backend
There apparently is a divergent on the models. BREP is the one most newer models are developing on. Used by build123d and CadQuery.
Compared to the constructive solid geometry (CSG) representation,
which uses only primitive objects and Boolean operations to combine them,
boundary representation is more flexible and has a much richer operation set.
In addition to the Boolean operations, B-rep has
extrusion (or sweeping), chamfer, blending, drafting, shelling, tweaking and
other operations that make use of these.
CSG is used by OpenSCAD, the most popular scripting cad.