The meteor now follows a ballistic parabola: constant horizontal speed and vertical speed growing under gravity solved from the launch and impact points, so it climbs slightly, bends over, and dives while speeding up. The trail samples past positions in time so it lengthens with speed, the head stretches along its velocity, and sparks inherit the meteor's velocity and fall under their own gravity.
wheelofnames
Self-hosted API that renders wheel-of-names GIF animations and gacha wish MP4 animations with Remotion.
API
POST /api/gif
Content-Type: application/json
Accept: image/gif
Authorization: Bearer change-me
{
"options": ["alice", "bob", "carol"],
"winnerIndex": 1,
"durationMs": 6500,
"holdMs": 1200,
"fps": 15,
"size": 512,
"theme": "classic"
}
Response is image/gif with winner metadata headers:
X-Wheel-Winner-IndexX-Wheel-WinnerX-Render-Duration-Ms
X-Wheel-Winner is URL-encoded so non-ASCII labels are safe in HTTP headers.
Gacha wish
POST /api/gacha
Content-Type: application/json
Accept: video/mp4
Authorization: Bearer change-me
{
"label": "Pizza",
"rarity": 5,
"fps": 24,
"width": 640
}
Renders a 7-second wish animation in the style of a gacha game: a meteor
coloured by rarity (blue 3★, purple 4★, gold 5★) falls across a night sky,
lands in a white flash, and the label is revealed beside a rank emblem (B,
A, S) with its stars popping in. Each tier is louder than the one below:
4★ adds a bigger meteor, a lens flare, impact shake, and a double shockwave;
5★ adds a rainbow halo before landing, a gold sky flood, a starburst, counter
rotating rays, falling sparkles, and a sheen across the emblem. The per-tier
table lives in src/remotion/gacha-timeline.js.
rarity is required; fps is 24 or 30; width is 640 (360 tall) or
854 (480 tall). The caller chooses the result and its rarity — the service
only draws it.
Response is a silent H.264 video/mp4 (Telegram plays it as an animation)
with X-Gacha-Rarity and X-Render-Duration-Ms headers. Both routes share the
MAX_CONCURRENT_RENDERS slots. All visuals are drawn procedurally; no game
assets are used.
Local
Install dependencies and Chromium once:
npm install
npm run browser:ensure
Start the local API:
npm run dev
Generate GIF files locally
Generate the quick smoke fixtures at the git-ignored paths
fixtures/smoke.gif and fixtures/gacha-5-star.mp4:
npm run render:smoke
Generate the complete fixture set at fixtures/smoke.gif,
fixtures/vietnamese.gif, fixtures/sixteen-options.gif, and
fixtures/gacha-{3,4,5}-star.mp4:
npm run render:fixtures
Render a custom GIF directly without starting the API server:
npm run render:local -- `
--output wheel.gif `
--option "Chiều nay uống CraneTea" `
--option "Chiều nay uống CraneTea" `
--option "Cà phê" `
--winner 1
macOS, Linux, or Git Bash:
npm run render:local -- \
--output wheel.gif \
--option "Chiều nay uống CraneTea" \
--option "Chiều nay uống CraneTea" \
--option "Cà phê" \
--winner 1
--winner is a zero-based index and is random when omitted. Run
npm run render:local -- --help for duration, hold, FPS, size, theme, and timeout
options. The documented root wheel.gif and fixtures/*.gif/*.mp4 outputs are
git-ignored and safe to delete; custom output paths may need their own ignore
rule.
Verify
Run the API smoke test and quality gates:
npm run api:smoke
npm run lint
npm run typecheck
npm test
Deploy
Use a container runtime first. Static-only platforms cannot satisfy
POST /api/gif because Remotion server rendering needs Node, Chromium/runtime
dependencies, and FFmpeg/compositor support.
docker build -t wheelofnames .
docker run --rm -p 3000:3000 -e API_TOKEN=change-me wheelofnames
Recommended starting resources: 1-2 vCPU and 1-2 GB RAM, with
MAX_CONCURRENT_RENDERS=1. RENDER_TIMEOUT_MS defaults to 15000 and is
raised to Remotion's 7000ms browser timeout floor when configured lower.
API_TOKEN is required when NODE_ENV=production.