solid123d

A bridge that runs SolidPython (OpenSCAD-style) code on the build123d BRep kernel. Change one import and existing code produces native build123d shapes instead of OpenSCAD source.

# before
from solid import translate, cube, scad_render_to_file
# after
from solid123d import translate, cube, scad_render_to_file

c = translate([10, 0, 0])(cube(10, center=True))
scad_render_to_file(c, filename="c.scad")  # writes c.step (real BRep geometry)

Every object returned is a plain build123d Shape, so bridged code mixes freely with native build123d — the intended migration path:

from build123d import fillet
from solid123d import cube

part = cube(20, center=True)
part = fillet(part.edges(), radius=2)   # native build123d from here on

Supported

• Primitives: cube, sphere, cylinder (incl. r1/r2 cones, d/d1/d2), square, circle, polygon (incl. paths holes), text
• Font resolution: text(font=...) matches fonts by family name the way fontconfig/OpenSCAD does (incl. "Family:style=Style" syntax), by scanning system font directories with fontTools and handing build123d the resolved file path. This fixes fonts with nonstandard subfamilies (e.g. "Academy Engraved LET", whose subfamily "Plain" makes OCCT's own lookup fall back to Arial).
• Transforms (callable style, translate(v)(obj, ...)): translate, rotate (vector, scalar, and axis-angle forms with OpenSCAD ordering), scale, mirror, resize, color, offset
• Booleans: union(), difference(), intersection() — plus native operators a + b, a - b, a & b
• 2D → 3D: linear_extrude (incl. center, scale; no twist), rotate_extrude (incl. partial angle)
• Export: scad_render_to_file writes .step/.stl; a .scad filename is rewritten to .step with a warning
• solid123d.utils: up, down, left, right, forward, back
• Typing aliases: OpenSCADObject and OpenSCADObjectPlus are aliases of build123d.Shape, so existing annotations like def some_obj() -> OpenSCADObject: remain correct

Known differences

• a * b intersection is not overloaded; use a & b or intersection()(a, b).
• hull() and minkowski() raise NotImplementedError (no BRep equivalent); in build123d these are usually a loft, sweep, offset, or fillet.
• linear_extrude(twist=...) raises NotImplementedError.
• $fn/segments arguments are accepted and ignored — BRep curves are exact.
• scad_render() (source string) raises NotImplementedError.
• OpenSCAD modifiers (#, %, !) and import()/surface()/projection() are not implemented.

Development

just test    # or: uv run pytest