MAINLINE

Digital consciousness stream. Matrix aesthetic · THX-1138 hue.

A full-screen terminal news ticker that renders live global headlines in large OTF-font block characters with a white-hot → deep green gradient. Headlines auto-translate into the native script of their subject region. Ambient mic input warps the glitch rate in real time. A --poetry mode replaces the feed with public-domain literary passages. Live messages can be pushed to the display over ntfy.sh.

Run

python3 mainline.py                      # news stream
python3 mainline.py --poetry             # literary consciousness mode
python3 mainline.py -p                   # same
python3 mainline.py --firehose           # dense rapid-fire headline mode
python3 mainline.py --refresh            # force re-fetch (bypass cache)

First run bootstraps a local .mainline_venv/ and installs deps (feedparser, Pillow, sounddevice, numpy). Subsequent runs start immediately, loading from cache.

Config

All constants live in engine/config.py:

Constant	Default	What it does
`HEADLINE_LIMIT`	`1000`	Total headlines per session
`FEED_TIMEOUT`	`10`	Per-feed HTTP timeout (seconds)
`MIC_THRESHOLD_DB`	`50`	dB floor above which glitches spike
`FONT_PATH`	hardcoded path	Path to your OTF/TTF display font
`FONT_SZ`	`60`	Font render size (affects block density)
`RENDER_H`	`8`	Terminal rows per headline line
`SSAA`	`4`	Super-sampling factor (render at 4× then downsample)
`SCROLL_DUR`	`5.625`	Seconds per headline
`FRAME_DT`	`0.05`	Frame interval in seconds (20 FPS)
`GRAD_SPEED`	`0.08`	Gradient sweep speed (cycles/sec, ~12s full sweep)
`FIREHOSE_H`	`12`	Firehose zone height (terminal rows)
`NTFY_TOPIC`	klubhaus URL	ntfy.sh JSON endpoint to poll
`NTFY_POLL_INTERVAL`	`15`	Seconds between ntfy polls
`MESSAGE_DISPLAY_SECS`	`30`	How long an ntfy message holds the screen

Font: FONT_PATH is hardcoded to a local path. Update it to point to whatever display font you want — anything with strong contrast and wide letterforms works well.

How it works

Feeds are fetched and filtered on startup (sports and vapid content stripped); results are cached to .mainline_cache_news.json / .mainline_cache_poetry.json for fast restarts
Headlines are rasterized via Pillow with 4× SSAA into half-block characters (▀▄█ ) at the configured font size
A left-to-right ANSI gradient colors each character: white-hot leading edge trails off to near-black; the gradient sweeps continuously across the full scroll canvas
Subject-region detection runs a regex pass on each headline; matches trigger a Google Translate call and font swap to the appropriate script (CJK, Arabic, Devanagari, etc.) using macOS system fonts
The mic stream runs in a background thread, feeding RMS dB into the glitch probability calculation each frame
The viewport scrolls through a virtual canvas of pre-rendered blocks; fade zones at top and bottom dissolve characters probabilistically
An ntfy.sh poller runs in a background thread; incoming messages interrupt the scroll and render full-screen until dismissed or expired

Architecture

mainline.py is a thin entrypoint (venv bootstrap → engine.app.main()). All logic lives in the engine/ package:

engine/
  config.py       constants, CLI flags, glyph tables
  sources.py      FEEDS, POETRY_SOURCES, language/script maps
  terminal.py     ANSI codes, tw/th, type_out, boot_ln
  filter.py       HTML stripping, content filter
  translate.py    Google Translate wrapper + region detection
  render.py       OTF → half-block pipeline (SSAA, gradient)
  effects.py      noise, glitch_bar, fade, firehose
  fetch.py        RSS/Gutenberg fetching + cache load/save
  ntfy.py         NtfyPoller — standalone, zero internal deps
  mic.py          MicMonitor — standalone, graceful fallback
  scroll.py       stream() frame loop + message rendering
  app.py          main(), boot sequence, signal handler

ntfy.py and mic.py have zero internal dependencies and can be imported by any other visualizer.

Feeds

~25 sources across four categories: Science & Technology, Economics & Business, World & Politics, Culture & Ideas. Add or swap feeds in engine/sources.py → FEEDS.

Poetry mode pulls from Project Gutenberg: Whitman, Dickinson, Thoreau, Emerson. Sources are in engine/sources.py → POETRY_SOURCES.

ntfy.sh Integration

Mainline polls a configurable ntfy.sh topic in the background. When a message arrives, the scroll pauses and the message renders full-screen for MESSAGE_DISPLAY_SECS seconds, then the stream resumes.

To push a message:

curl -d "Body text" -H "Title: Alert title" https://ntfy.sh/your_topic

Update NTFY_TOPIC in engine/config.py to point at your own topic. The NtfyPoller class is fully standalone and can be reused by other visualizers:

from engine.ntfy import NtfyPoller
poller = NtfyPoller("https://ntfy.sh/my_topic/json?since=20s&poll=1")
poller.start()
# in render loop:
msg = poller.get_active_message()  # returns (title, body, timestamp) or None

Ideas / Future

Performance

Concurrent feed fetching — startup currently blocks sequentially on ~25 HTTP requests; concurrent.futures.ThreadPoolExecutor would cut load time to the slowest single feed
Background refresh — re-fetch feeds in a daemon thread so a long session stays current without restart
Translation pre-fetch — run translate calls concurrently during the boot sequence rather than on first render

Graphics

Matrix rain underlay — katakana column rain rendered at low opacity beneath the scrolling blocks as a background layer
CRT simulation — subtle dim scanlines every N rows, occasional brightness ripple across the full screen
Sixel / iTerm2 inline images — bypass half-blocks entirely and stream actual bitmap frames for true resolution; would require a capable terminal
Parallax secondary column — a second, dimmer, faster-scrolling stream of ambient text at reduced opacity on one side

Cyberpunk Vibes

Keyword watch list — highlight or strobe any headline matching tracked terms (names, topics, tickers)
Breaking interrupt — full-screen flash + synthesized blip when a high-priority keyword hits
Live data overlay — secondary ticker strip at screen edge: BTC price, ISS position, geomagnetic index
Theme switcher — --amber (phosphor), --ice (electric cyan), --red (alert state) palette modes via CLI flag
Persona modes — --surveillance, --oracle, --underground as feed presets with matching color themes and boot copy
Synthesized audio — short static bursts tied to glitch events, independent of mic input

Extensibility

serve.py — HTTP server that imports engine.render and engine.fetch directly to stream 1-bit bitmaps to an ESP32 display
Rust port — ntfy.py and render.py are the natural first targets; clear module boundaries make incremental porting viable

macOS only (system font paths hardcoded). Python 3.9+.

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