render-imessage-cascade

The free, deterministic renderer for the imessage-notification-cascade video ad format — the viral iOS trend where a phone lies face-up (the source: on a desk) and Apple Messages notifications STACK IN one after another. The signature mechanic is the bottom-up push: each new banner springs in at the bottom (nearest the phone) and shoves every existing one UP a row; the iOS grouped "⌄ Show less / ✕" pill rides above the stack; the ✕ clears the stack; then a serif end card resolves.

This is a DETERMINISTIC composite — no generative video of the UI. Authentic iMessage banners are drawn in PIL and animated in FFmpeg over a Ken-Burns plate, so the notification text + wordmark stay pixel-crisp (a video model would smear type). The template recipe supplies the per-brand plate, notifications, and end_card config and gates the only paid steps — cleaning the plate (→ create-image-fal) and the music bed/pop (→ create-music-elevenlabs) — to their own capabilities. This capability itself makes no paid calls.

Choices

The creative calls are the user's, asked by the format recipe before any paid step; this renderer draws whatever the config holds.

• setting — where the phone lies (the plate). The demo used a desk in a dim, moody home office.
• message_story — what the messages tell (inbound leads, a friend's texts, order alerts, a group chat, a problem solved) → notifications[]. The demo used inbound leads.
• audio — pops + swoosh only, or a bed (lo-fi / upbeat / tense) + pops → config.audio. With no bed, compose.py plays the pops + swoosh over silence; --no-audio is fully silent. The demo used a soft music bed.

Scripts (free)

• scripts/build_assets.py — draws the assets from config: nb-1..N.png (authentic banners — green Messages icon, warm translucent-greige fill, soft box-shadow, title/body/NOW/handle), pill.png (right-aligned "⌄ Show less / ✕"), endcard.png (serif CTA + wordmark lockup + url). Fonts are load-bearing: SF Pro (SFNS.ttf) via set_variation_by_name for the banner title/body/NOW/handle (Arial fallback), Times/serif for the end-card CTA. Do NOT swap in Helvetica/Arial as the primary — the banners must read as the real iOS system font.
• scripts/compose.py — Ken-Burns push-in on the plate → each banner springs in at the BOTTOM while later arrivals push the stack UP (FFmpeg overlay y expressions) → pill rides above → ✕-clear swipes the stack up + fades → serif end card fades in → optional audio (optional bed + pop per arrival + a free FFmpeg swoosh on the clear) → encode h264 + aac.
• scripts/config.example.json — the shape of the brand config the recipe binds.

Geometry contract (load-bearing — build_assets.py and compose.py MUST share it)

W=1080 H=1920, SIDE=135 → banner width BODY_W=810, BANNER_H=176, PAD=60, row pitch H=214, bottom anchor YB=1200. Icon ~100px at a ~24px left inset; body text starts ~150px from the banner's left edge. Change one, change both.

Craft rules (faithful to the source molecule)

• Keep the REAL iMessage UI: green Apple Messages icon, warm TRANSLUCENT greige banner (NOT white, no white bloom), soft dark box-shadow. Do NOT rebrand the banner to the brand's colors — the brand lives ONLY on the handle (bottom-right) + the end card.
• SF Pro for all banner text (title Semibold ~38, body Regular ~36, NOW/handle ~25). Never AI-render text.
• 3–5 notifications (more crowds the top / clips the pill); newest enters at the BOTTOM, so banner 1 is the oldest and ends up on TOP.
• ✕-clear then end card (a real hand-swipe needs a paid i2v — out of scope here).

Requires

watch (QC the final master). The recipe gates create-image-fal (plate clean) and create-music-elevenlabs (bed/pop) — both paid, proxy-routed, billed to the Ads agent.

Wrapped notifications and software endings

Bodies are measured and wrap to two lines. Oversized words, excessive lines, titles/handles that do not fit and stacks outside the safe area fail with a correction request. Shorten copy or reduce the notification count; never silently truncate or shrink the type. Asset building writes shared geometry and a config signature. Compose requires that manifest and rejects changed inputs until assets are rebuilt. Single-line configs retain their established dimensions and timing.

An optional resolution object supplies title, body and handle after the stack clears, plus an optional arrival time, hold duration and supplied sound file. Omit the old explicit end-card/duration overrides when using derived resolution timing. It holds at least 1.5 seconds before the ending. Missing supplied audio fails rather than silently disappearing.

For a software ending, set the end-card layout to b2b and supply a verified quote, attribution, optional CTA, a font file and one or two logo files. Logos retain their aspect ratio and transparency. Missing fonts/assets and excessive copy fail. Neutral layout samples are not customer endorsements.