pycodecad

Code-CAD with build123d: write a Python script, see the part, export it for 3D printing.

from build123d import Box, Cylinder
from pycodecad import show

plate = Box(40, 30, 8) - Cylinder(5, 8)
show(plate, name="plate", color="#F4B02A")

Install

pip install pycodecad        # Python 3.12+, OpenGL 3.3

Quick start

pycodecad examples                    # copy the examples to ./pycodecad-examples and open them
pycodecad part.py                     # a window on part.py (created from an example if missing)
pycodecad parts/gear/                 # a window on a folder: a part in several files
pycodecad check part.py               # run it without a window, print the result as JSON
pycodecad export part.py part.stl     # also .3mf .step .glb .brep

What you get

• A window on a part: its files, the code and the part side by side. It runs the part once when it opens, then only when you press Run, and writes only when you press Save.
• Parameters: expose(fn) turns the arguments of a function into sliders, number boxes and checkboxes.
• Animations: frame() saves the scene as a frame; the window plays them. Parts built once and moved with Pos are not computed again, so mechanisms play in real time.
• A command line: check, render and export run the same script without a window.
• An AI workflow: an assistant edits the file and checks its own work with check and render.
• Parts for your own app (experimental): the window's code, parameters and 3D view as Dear ImGui components, in pycodecad.embed.

Parameters from expose()	Errors point at the line	pycodecad render: what an AI sees

pycodecad is small on purpose, readable in an afternoon: see Design.

Documentation

• Getting started: install, a first part, run, export.
• The window: layout, Run and Save, Reload, read-only mode, shortcuts.
• Parameters: expose(), its controls and --set.
• Scripts: show, clear, frame (animations), import_mesh, colors, paths, errors.
• Command line: check, render, export, context, exit codes.
• Working with an AI assistant: the AI context and how an assistant checks its work.
• Files: everything pycodecad writes, and where.
• Embedding: the window's parts in your own app (experimental).
• Design: principles, platforms and plans.
• Development: tests, type checks and releases.

Examples: examples/

Credits

• build123d: the modeling language
• Open CASCADE and OCP: the geometry kernel
• Dear ImGui and slimgui: the interface
• ModernGL, GLFW and pyGLFW: rendering and windows
• NumPy: meshes
• pytypehint: the parameters of expose()
• Lucide: icons (ISC)

License

MIT