OpenSCAD is kinda neat

Original Article ↗ Hacker News Discussion ↗

Maintenance & Versions

  • Project is still active on GitHub; core is under ongoing development.
  • Official release (2021.01) is widely considered obsolete; users recommend nightly/snapshot builds instead.
  • Nightlies default to the new Manifold backend, which many say makes rendering 10–100x faster, though a few report occasional visual/occlusion glitches.

Performance & Kernel

  • With Manifold backend and “lazy unions” enabled, complex models (many holes, SVG imports, gears) can render in seconds instead of minutes.
  • Some users still find the kernel “falls apart” for advanced CSG operations or very complex assemblies. Others report it handling huge extruded SVG maps and intricate parts better than competing tools.

Strengths & Typical Use Cases

  • Very popular for small, functional 3D-printed parts: adapters, enclosures, hooks, gears, fasteners, brackets, microscope parts, etc.
  • Text-based, parametric nature is praised: easy to tweak dimensions, generate families of parts, and use version control (diffs, branching) like software.
  • Especially appealing to programmers; many describe it as “CAD for developers” or “graphics programming with primitives + set operations.”

Language & Workflow

  • The functional-ish language is seen as both elegant and weird: immutable-style variables, modules vs functions, recursion instead of loops.
  • Critiques: hard to write non-geometry helper functions, no partial evaluation / querying of geometry (e.g., “attach surface A to surface B”), heavy reliance on math and “epsilons” to avoid coincident faces.

Limitations & Missing Features

  • No native STEP export; STL/DXF-only output limits downstream CAD/assembly workflows.
  • Pain points: proper fillets/chamfers, rounding edges, constrained sketching, selecting faces from the viewport, working with arcs, and modeling parts to match real-world geometry.
  • Larger models historically became very slow; Manifold alleviates but doesn’t remove all performance issues.

Ecosystem, Alternatives & LLMs

  • BOSL2 library strongly recommended for fillets, chamfers, screws, gears, attachments, and higher-level primitives.
  • Alternatives mentioned: CadQuery, build123d, PythonSCAD, SolidPython, OpenJSCAD, Fornjot, Zoo/KCL, FreeCAD, Fusion 360, Onshape, Dune3D, SolveSpace.
  • Many report good results using LLMs to generate or modify OpenSCAD code, especially for simple or moderately complex parts, though models often lack robust “spatial intuition.”