8bit Fireplace

A full-screen 8-bit fireplace for Screenly digital signage screens — a burning pixel-art log pile with drifting embers and firelight moving across the firebrick behind it.

There is deliberately no drawn surround, mantel or caption: the screen's own bezel frames the hearth, so the TV itself becomes the mantelpiece.

How it works

The whole picture is one small canvas — around 280x155 pixels — upscaled by a whole number of device pixels and drawn with image-rendering: pixelated. That keeps every chunky pixel exactly square from 480x800 up to 4096x2160, and means the cost per frame barely changes with the display's resolution.

• Flames are the classic cellular "Doom fire": heat seeded along the top of the log pile, spreading one row up per tick with a little random loss. It runs at a fixed 30 ticks per second regardless of the display's refresh rate, and is pre-warmed at startup so a screen never shows a cold hearth.
• Firelight is palette animation, not per-pixel shading. Each static pixel stores a colour plus how exposed it is to the fire; lighting a frame is one lookup per pixel against a pre-baked table. The band edges are dithered with an ordered 4x4 matrix so the light does not read as concentric rings.
• Colours come from a 16-colour scene palette and a 15-step flame ramp.
• The logs are composited over the flames, so the fire licks up between them, and they are deliberately lit less than the brickwork — a pile lit to the same degree turns into pale sandstone rather than firewood.

The brickwork is generated from a seed derived from the screen's hostname, so each screen gets its own firebox but always looks the same after a restart.

Configuration

Setting	Description	Required	Default
crt_effect	Overlay CRT-style scanlines	No	false
flame_color	classic, azure, emerald or violet	No	classic
flame_height	low, medium or high	No	medium
pixel_size	chunky, classic or fine	No	classic
scene	hearth for the log fire, inferno for a full screen of flame	No	hearth
sentry_dsn	Sentry DSN for error reporting; leave empty to disable	No	(empty)

An unrecognised value falls back to its default rather than blanking the screen.

The app deliberately ignores the workspace's branding colours: the palette is fixed, and recolouring it would break the period look. Use flame_color to change the mood instead.

Use of @screenly/edge-apps

Settings, metadata, the ready signal, error handling, Sentry reporting, the base reset and design tokens, the shared ESLint/Vite/Playwright tooling and the screenshot and mock helpers all come from the library.

Two things are deliberately not used:

• <auto-scaler> / initEdgeApp() scale a fixed 1920x1080 reference box with a fractional CSS transform and letterbox whatever does not fit. That is right for a layout-based app and wrong for this one: it resamples the pixel art and leaves dead bars. Measured on a real player frame, the app's own integer upscale keeps 100% of pixel blocks a single flat colour, whereas the same frame through <auto-scaler> is 54% impure at 800x480 and loses 44% of a 1080x1920 screen to letterboxing. The app sizes its own canvas instead.
• base/fonts.css (via the @screenly/edge-apps/styles barrel) inlines ~450 kB of base64 Inter. This app renders no HTML text, so it imports the reset and tokens directly and ships 0.9 kB of CSS.

Getting Started

Install dependencies:

bun install

Development

bun run dev

Testing

bun run test
bun run lint

Build

bun run build

Screenshots

bun run screenshots

Deployment

screenly edge-app create --name 8bit-fireplace --in-place
bun run deploy
screenly edge-app instance create

Stage and production share a single screenly.yml with no id. The Edge App ID for each environment is supplied by GitHub:

Source	Used when
EDGE_APP_ID environment secret	Set on the stage or production GitHub Environment (takes precedence)
STAGE_EDGE_APP_ID repository variable	Fallback for stage
PRODUCTION_EDGE_APP_ID repository variable	Fallback for production

Run Initialize Edge App against stage or production to create the app, then store the printed id in the matching variable (or environment secret). Update Edge App deploys on push to development (stage) and master (production), and can also be run by hand against stage.