1-bit Jaws

A 1-bit frame of Jaws, advancing every 15 minutes. Live at jaws.superfun.games and on TRMNL e-ink displays.

How it works (time-based, no redeploys)

The current frame is a pure function of the clock, so nothing has to be committed or redeployed to keep the display correct. This is the whole point of the current design: the previous version committed a new public/current.png every 15 minutes via a GitHub Action, and every commit triggered a Netlify deploy (~96 paid deploys/day). That's gone.

• Frames: frames/seq-0001.png … frames/seq-5301.png — 5,301 contiguous 1-bit stills, served statically.

• The math lives in two mirrored files (keep their constants in sync):

  • frame.js — browser version, used by index.html and screen.html.
  • netlify/functions/_frame.mjs — Node version, used by the functions.

  The sequence is phased as a countdown to the upcoming July 4th night:

  index = (5300 - floor((nextJuly4Night - now) / 15min)) mod 5301
  

  So the final frame (seq-5301.png) always lands on July 4th night (9:00 PM US Eastern by default — see END_HOUR_ET). The ~55-day straight run before it plays cleanly from seq-0001.png to seq-5301.png (5,301 × 15 min ≈ 55 days, starting ~May 10th). The target automatically rolls to the next year after July 4th passes, so it ends on July 4th every year with no code change, and the sequence loops in between.

  One consequence of pinning a fixed calendar date to a ~55-day loop: just after July 4th night the countdown re-targets next year and the frame jumps once (mid-sequence) before continuing to loop forward toward the next July 4th. This single yearly re-sync is unavoidable unless the loop length divides a year evenly.

• Website: index.html / screen.html compute the frame client-side, show it, and swap to the next one exactly at each 15-minute boundary. No backend.

• TRMNL: netlify/functions/ping-trmnl.mjs runs on a 15-minute schedule and POSTs the current frame to the TRMNL custom-plugin webhook. Function invocations do not trigger deploys, so this costs nothing extra. The payload keys match the old function so the TRMNL template keeps working.

• Legacy current.png: netlify/functions/current-frame.mjs 302-redirects /current.png and /public/current.png to the correct frame, so old links stay correct without committing anything (wired up in netlify.toml).

Changing things

• Cadence: change INTERVAL_MS in both frame.js and _frame.mjs (and the cron in ping-trmnl.mjs's config.schedule).
• Ending time: change END_HOUR_ET (and ET_UTC_OFFSET if not US Eastern) in both files to move when the final frame shows on July 4th night.
• Tests: npm test (runs node --test) verifies the frame math and that the referenced frame files exist.

Notes

• _data/image_counter.txt and _data/image_list.txt are leftovers from the old GitHub Action flow and are no longer read by anything.
• Deploys now only happen when you actually push site changes — not on a timer.