[bangaladore]

> That's the beauty of constraint-based parametric modeling as opposed to, say, modeling in Blender.

I was thinking the same thing. This looks more like an API that makes 3d modeling look closer to CAD, but without realizing that CAD is about constraints, parametrizing, and far more.

[throwup238]

> but without realizing that CAD is about constraints, parametrizing, and far more

Constraints and parametrizing are the trivial parts of CAD, something you can now implement in a weekend with Claude Code, the MINPACK/SolveSpace test suite, and OpenCascade as an oracle. The hard part is a geometric kernel that can express boundary representations for complex shapes (sketches, chamfers, fillets, etc) and boolean operations while somewhat handling the topographical naming problem without driving the user insane (which existing kernels are still all shit at).

[delusional]

> Constraints and parametrizing are the trivial parts of CAD, something you can now implement in a weekend with Claude Code

You go ahead and try that.

[tomcur]

We've started a 2D geometric constraint solver at https://github.com/endoli/fiksi doing the constraint part of this in Rust. We're using it internally and so far it works well, though it's still experimental. More constraints and especially better behavior around failure are needed. The latter will likely entail at least doing more with degree of freedom counting, though there's some of that already.

A C++-library to be aware of is SolveSpace's slvs: https://github.com/solvespace/solvespace/tree/e74c2eae54fdd9....

[imtringued]

This is something I don't get about the code-based CAD tools. They don't let you specify declarative geometric constraints.

Constraints are useful beyond just designing parts. If you have a parallel mechanism there are only two ways to solve the kinematics/dynamics for it: Constraint solving for rigid contacts or iterative solving by approximating the model with non-rigid contacts via internal springs.

[WillAdams]

Could you mock up some code to describe which you feel would be suitable to describing such a thing?