Install

Python 3.11 to 3.13 (3.13 recommended). The simplest way is uv, which fetches Python and the library to run a script:

uv run --python 3.13 --with axonometry script.py
uv run --python 3.13 --prerelease=allow --with axonometry script.py   # release candidates

or install it like any package: pip install axonometry.

How it works

from axonometry import Axonometry, Line, Point

my_axo = Axonometry(30, 30)                       # an isometric system
line = my_axo.xy.draw_line(Line(Point(x=70, y=40), Point(x=70, y=15)))  # a line in the plan
line.project(distance=80)                         # the same line, 80 mm above the plan
my_axo.save_svg("first_drawing")                  # the SVG file, in ./output/

An axonometry is four planes: the picture plane, where points have three coordinates, and three reference planes — the plan xy and the elevations yz and zx — tilted into the paper. A point in space is never computed by a projection matrix. Its views are drawn in two reference planes, and the point is where their projection lines cross:

view in xy ─┐
            ├→ projection lines → intersection → point in the picture plane
view in zx ─┘

The construction stays in the drawing, on its own layer: the SVG file has one layer per pen (system, construction traces, geometry, hatches), with the paths in the order of the construction. Many defaults are random: the same script never makes quite the same drawing.

Development

git clone https://codeberg.org/mononym/axonometry.git
cd axonometry
git switch dev             # contributions branch from dev
uv sync                    # package + dev dependencies

CI (Woodpecker) runs the tests on Python 3.11, 3.12 and 3.13, the lint and the license check.

Layout:

src/axonometry/
  axonometry.py          the entry point: a system, its four planes and its drawing
  trihedron.py           the axes on the paper and the tilt of the reference planes
  plane.py               picture plane and reference planes, where geometry is drawn
  point.py, line.py      the elements; the line is the element of a plotter drawing
  surface.py, volume.py  closed polygons and prisms
  hatch.py               fill styles, measured in true size
  operations.py          geometric questions answered by construction
  drawing.py, paper.py   the record of the paths, SVG export, papers and pens
  axo_config.toml        layers, pens and colors
docs/source/             Sphinx docs (tutorial, how-to, explanation, reference)
examples/                example scripts and files

Before adding a feature, read the design principles and the contribution guide. Feedback of any kind is welcome, and doesn’t require software development skills.

Issues and contributions: https://codeberg.org/mononym/axonometry/issues

Acknowledgements

• compas for the geometry and vpype for the plotter-ready SVG. Not only did their libraries make this project possible, but reading their codebases was an invaluable way to learn Python.

Licenses

• axonometry: GNU General Public License v3.0 or later

• documentation & images: Creative Commons Attribution 4.0 International

• test drawing tests/bunny.svg: Creative Commons Attribution-ShareAlike 4.0 International

• configuration, CI and generated files: CC0 1.0 Universal