EN

Fractal Flame

A fractal flame generator in Python: the Chaos Game (IFS) algorithm, multiprocess rendering that merges the workers' histograms, gamma correction and rotational symmetry.

Period
November 2025 — June 2026
Status
Completed
My role
Sole developer: the algorithm, parallel rendering, CLI and configuration.
Source code
Aurora — an example of a generated fractal flame

Stack

  • Python
  • NumPy
  • multiprocessing

Key technical decisions

  • Rendering is split across processes, and the workers' histograms are merged into one.
  • Gamma correction after the logarithmic density transform: without it the image comes out flat.
  • Rotational symmetry as a separate parameter of the composition.
  • Parameters come from the CLI and a JSON config, so any frame can be rebuilt from the one it was made with.
  • Strict typing checked by mypy, unit and integration tests, linting and CI.

An implementation of the fractal flame algorithm: a large number of points are run through a set of affine and non-linear transforms following the Chaos Game (IFS) scheme and accumulated in a density histogram, which then goes through a logarithmic transform and, after it, gamma correction.

Rendering runs in one process or several, and the parallel results merge into a single histogram. The worker count affects speed. Each worker also follows its own sequence of random points, so frames built with different process counts can differ in small details.

What gamma correction buys

Point density is heavily skewed: without gamma correction almost everything lands in the dark tones and the structure disappears. The correction brings out detail in the low-density regions without blowing out the dense ones. Here is the same frame with it and without:

Gamma correction off
Gamma correction off
Gamma correction on
Gamma correction on

Every example on this page has a config behind it. They all live in the repository, and the two frames above differ by a single value in them.

Media

  • Constellation — sparse, star-like structure, 5-fold symmetry
    Constellation — sparse, star-like structure, 5-fold symmetry
  • Aurora — soft gradients, 9-fold symmetry, gamma correction
    Aurora — soft gradients, 9-fold symmetry, gamma correction
  • Neon Flower — 8-fold radial symmetry, high colour contrast
    Neon Flower — 8-fold radial symmetry, high colour contrast
  • Phoenix — 11-fold radial symmetry, four combined transformations
    Phoenix — 11-fold radial symmetry, four combined transformations
  • Ember Ring — ring-like structure, 6-fold symmetry
    Ember Ring — ring-like structure, 6-fold symmetry
  • Pretty Flame — several transformations, symmetry and gamma correction
    Pretty Flame — several transformations, symmetry and gamma correction
  • Spiral Core — central spiral structure, no symmetry
    Spiral Core — central spiral structure, no symmetry
  • Soft Smoke — smoke-like gradients, no symmetry
    Soft Smoke — smoke-like gradients, no symmetry