These code base cad systems are pretty great. But all of them are imperative languages and as such can only solve imperative constraints. Including declarative constraints would be very welcome. I mean, sure, Theoretically we could enter the turing tarpit and build our own constraint solver, but it would be nice to see one included as a standard library.
I am trying to think of an example, declarative constraints are usually the domain of a graphical cad system(like solvespace). but I suspect it would look like a set of relationships you can enter in any order and it solves for the missing one. so... prolog? has there ever been a cad system in prolog?
The constraints solving took a good amount of thinking while designing FluidCAD. At first I tried to make it all declarative where user just create unconstrained geometries then define constraints, something like: const l1 = line(); const c1 = circle(); // define constraint l1.length(100).position(x, y).tangentTo(c1) ...
Then I decided against this idea because it results in too much typing + the constraint solver implementation is not trivial and there is not much web based open source solvers. I went with a mixed approach instead between declarative and imperative. https://fluidcad.io/docs/guides/sketching/constrained-geomet...