---
title: 'Matrix Rain: 2025 refactor'
date: 2025-12-21
layout: post
project: true
thumbnail: thumb_sm.png
---

Unicode support added. ASCII + Katakana working:

<video style="max-width:100%;" controls="" poster="poster.png">
  <source src="matrix.mp4" type="video/mp4">
</video>

Algorithm notes: mat.col[] = shuffled column indices, mat.row[] = last row per
column. shuffle() sets working set, main loop draws columns via index i (line
333), swap() rotates set.

Phosphor decay moved to LSB of RGB union. Should have done this originally.

RGB/PD union stays. Little-endian machine, portability not a concern.

Charset via UNICODE(min, max) macro - packs range into uint64, insert_code()
unpacks and selects random char.

Half-width Katakana (U+FF61-U+FF9F) for column alignment.

Removed license, automake files. Build: cc -O3 main.c -o matrix

Performance: 2% CPU, OpenBSD, T490.

Commit:
[03f8d87](https://git.asciimx.com/matrix-digital-rain/commit/?id=03f8d87ba7c2e46bd3f3cc4c772fb3a2ac740c92)