07 Dec 2017

*Tags: geometry
,
python
,
antiprism
*

Antitile is a Python package for manipulating polyhedra and tilings. It is largely a collection of add-ons and scripts to be used with for Adrian Rossiter’s Antiprism, but can be used on its own. Documentation is available on readthedocs.io. The most interesting programs in the package are these:

`gcopoly.py`

: The Goldberg-Coxeter subdivision operation of tilings. Basically it makes things that look like geodesic domes, or the quadrilateral-faced analog of geodesic domes. Antiprism itself implemented the triangular version of this in the`geodesic`

, but not the quadrilateral case. This also implementes a handful of new projections.`balloon.py`

: Balloon tiling of the sphere. Take a regular triangular or quad grid, wrap it around a sphere in a certain way.`cellular.py`

: Colors polyhedra (faces or vertices) using cellular automata.`view_off.py`

: Viewer for`.off`

files, the format used by Antiprism. Antiprism has`antiview`

but I wanted something to create`.svg`

files.

Roger Kaufman from the Antiprism Google group made an animation using `gcopoly.py`

and `cellular.py`

, using the rules of Conway’s Game of Life:

- 2023-11-04: Spherical area coordinates, and a derived triangle center
- 2023-07-29: Homogeneous coordinates on the sphere with vectors
- 2022-08-30: Scaling the Schwarz triangle function
- 2022-08-27: Edges in the image of the Schwarz triangle function
- 2022-07-20: Area-preserving swirling of the disk
- 2022-03-03: Some dubious ways to calculate conformal polyhedral projections
- 2021-10-02: A variation on the Chamberlin trimetric map projection
- 2021-08-31: Snyder's equal-area projection
- 2021-06-12: Perspective projections with vectors
- 2021-05-29: A (sort of) Euclidean triangle on a non-Euclidean surface