I've been in the programmatic CAD space for a while, and the core issue isn't geometry generation, it's the feedback loop.
Current approaches hit the same wall: you can't easily go from geometry back to code. When an LLM generates OpenSCAD and the output is wrong, you're staring at an STL with no way to point at a face and say "this edge should be 2mm
shorter." The LLM is flying blind.
The tools that work best right now are the ones that keep geometry minimal and code iterative. OpenSCAD with an LLM in a loop can handle simple parts because the code is the source of truth and changes are surgical. But complex
assemblies? The boolean operations cascade failures in ways that are brutal to debug even for humans.
The real unlock isn't better prompting or bigger models: it's a representation that supports bidirectional editing. F-Rep/SDFs are interesting here because the math is more compositional and less "undo history dependent" than B-Rep.
Manufacturing constraints (tolerances, printability, material limits) are a separate unsolved problem. Geometry that looks right but won't print is the silent killer.
Comments
I've been in the programmatic CAD space for a while, and the core issue isn't geometry generation, it's the feedback loop.
Current approaches hit the same wall: you can't easily go from geometry back to code. When an LLM generates OpenSCAD and the output is wrong, you're staring at an STL with no way to point at a face and say "this edge should be 2mm shorter." The LLM is flying blind.
The tools that work best right now are the ones that keep geometry minimal and code iterative. OpenSCAD with an LLM in a loop can handle simple parts because the code is the source of truth and changes are surgical. But complex assemblies? The boolean operations cascade failures in ways that are brutal to debug even for humans.
The real unlock isn't better prompting or bigger models: it's a representation that supports bidirectional editing. F-Rep/SDFs are interesting here because the math is more compositional and less "undo history dependent" than B-Rep.
Manufacturing constraints (tolerances, printability, material limits) are a separate unsolved problem. Geometry that looks right but won't print is the silent killer.