omardelarosa/strata

Hierarchical cellular automata

Strata

QuadTree-based cellular automata rendering in Python.

Installation

Python3+ is recommended.

pip install pyglet numpy

Usage

usage: strata [-h] [--width WIDTH] [--height HEIGHT] [--depth DEPTH]
              [--slice SLICE] [--out OUT] [--steps STEPS]

Renderer for hierarchical cellular automata

optional arguments:
  -h, --help       show this help message and exit
  --width WIDTH    Width of window
  --height HEIGHT  Height of window
  --depth DEPTH    Maximum recursion depth of tree
  --slice SLICE    Show only a 1-layer slice
  --out OUT        Output directory for screenshots
  --steps STEPS    Number of steps before terminating (-1 == infinity)}

# 128x128 matrix, levels 0-7 only, 10 iterations
python3 . \
--width 128 \
--height 128 \
--depth 7 \
--out screenshots \
--steps 10

Examples

Two rulesets have been implemented:

1. Conway
2. Gamma

Conway

An update rule based on conway's game of life using the neighbor nodes + children + parent values to determine updates.

Note: the "leaf" level (i.e. 1x1 pixel grid) is "immutable" and remains constant from t=0 onward.

Sparse Initial Matrix

PROBABILITY_OF_LEAF_ALIVE_ON_START=0.02

t	screenshot	notes
0		Initialization, hardly any pixels
1
2
3
4
5
6
7
8
9
10		Mostly stable structures, cyclical updates

Gamma

A custom rule based on the unique properties of the quad tree.

Sparse Initial Matrix

PROBABILITY_OF_LEAF_ALIVE_ON_START=0.000001

t	screenshot	notes
0		Initialization, hardly any pixels
1
2
3
4		Grid emerges
5		Grid of grids emerges
6
7
8
9		Grids oscillate
10

Dense Initial Matrix

PROBABILITY_OF_LEAF_ALIVE_ON_START=0.05

t	screenshot	notes
0		Initialization, hardly any pixels
1
2
3
4		Grid emerges
5		Noisier grid of grids emerges
6
7
8
9
10		Less defined grids?

Other Neat-Looking Artifacts

Here are a couple of neat looking artifacts that came out of the process:

QuadTrees

QuadNoise

Vertex Triangulation

Timeseries