animated-loop

animated-loop — 3-5 Second Seamless Background Loop

A loop is the only video format that has to not have a beginning or end. The viewer sees it on the title screen for 30 seconds; if the seam between loop iterations is visible, the whole thing reads as broken. This skill exists to force the constraints that make seams invisible: keep the duration short (3-5s), keep the motion ambient (no narrative, no big camera moves), use the cheap fast model (ltx), and prompt for a composition where the first and last frames are functionally identical.

If the user wants a 5s punchy marketing shot, that's video/trailer-shot. If they want a 10s narrative cutscene, that's video/cinematic-cutscene. This skill is the one for video that has to disappear — atmosphere behind a logo, mood behind a menu, ambience behind a splash card.

When to use

• "Looping background for the title screen."
• "Animated backdrop behind the logo on the splash."
• "Menu background — torchlit dungeon, just flicker and motes."
• "Looping ambient video for the pause screen."
• "Splash loop — fog over a forest."
• "Need a video that loops behind the level select."

When NOT to use

• Marketing shot for a trailer (5-10s with punch) — video/trailer-shot.
• Narrative cutscene with a beginning and end — video/cinematic-cutscene.
• Static splash image — generate with 2d-assets/concept-art and use a TextureRect. A still is cheaper, lighter, and never seams.
• UI element animation (icons, button states) — those are GDScript Tween or sprite sheets, not video.
• A 10-second shot you want to "loop". That seam will be visible. Either accept a hard cut every 10s (ugly) or generate a 3-5s clip designed to loop.

Steps

1. Confirm the loop will be visible for a long time

Quick check — this loop will play on a screen the user might stare at for 30+ seconds. That means the loop point must be invisible. I'll keep it 3-5s and prompt for ambient motion (drift, flicker, shimmer) rather than a narrative beat. OK?

If the user wants narrative motion (a character walking, a door opening), this is the wrong skill — route to video/cinematic-cutscene.

2. Pick the model — ltx first, always

For loops, ltx is correct ~95% of the time. It's $0.10, ~30s, and the constraints (short duration, ambient motion) are exactly the ones ltx handles best. Premium models add cost without adding loop quality.

Model	Cost	Speed	When
ltx	~$0.10	~30s	Default. Use this.
kling	~$0.50	2-4 min	Only if the loop is the centerpiece of a premium splash and quality is visibly lacking on ltx
kling-turbo	~$0.30	1-2 min	Same as kling but faster
veo3	~$1.00	3-5 min	Almost never — veo3 shines on dialogue/identity, neither matters for ambient loops
minimax	~$0.40	2-3 min	Stylized / anime aesthetic loops

3. Lock the look with a reference still

The reference still doubles as the target loop frame. Generate it deliberately — the video model's first and last frames will gravitate toward the reference, which is exactly what you want for a closing seam.

summer_generate_image(
  prompt="<subject>, ambient atmospheric scene, cinematic lighting, painterly, balanced composition with no clear focal action",
  model="nano-banana-2",
  options={ image_size: "landscape_16_9" }
)

For vertical menus (mobile portrait splash), generate at portrait and use aspectRatio="9:16" on the video call.

4. Prompt for loopable motion only

Loopable motion is continuous, ambient, directionless, or oscillating. Avoid anything with a beginning or end (a character entering, a sword swinging, a door closing).

Loopable verbs: drift, flicker, swirl, shimmer, sway, pulse, glow, rise, fall, wave, breathe, ripple.

Non-loopable verbs (avoid): walks, enters, appears, emerges, transforms, attacks, falls down, opens, closes.

summer_generate_video(
  prompt="<subject from reference>, <ambient loopable motion>, slow continuous, looping, seamless, cinematic",
  model="ltx",
  imageUrl="<reference URL from step 3>",
  duration=4,
  aspectRatio="16:9",
  options={ negative_prompt: "sudden movement, character action, narrative event, fade to black" }
)

The phrase "looping, seamless" in the prompt biases the model toward stable first/last frames. The negative prompt rules out narrative drift.

5. Inspect the seam

Watch the result and the seam (the cut between the last and first frame on replay). If the seam is visible:

• Most common cause: something moved across the frame and didn't return (a particle drifted off-screen, a cloud moved). Regenerate with slow continuous, returning motion, oscillating in the prompt.
• Second cause: lighting drifted. Regenerate with constant lighting, no time of day change.
• Third cause: the duration was too long. Drop from 5s to 3s and regenerate.

If three regenerations don't seam-close, accept a small crossfade in the engine: set up two VideoStreamPlayer nodes and crossfade between them via a Tween. This is a fallback, not the goal.

6. Import and wire as a looping VideoStreamPlayer

summer_import_from_url(url="<fileUrl>", path="assets/video/loops/title_screen_bg.ogv")

Note: Godot's VideoStreamPlayer natively plays Ogg Theora (.ogv); for .mp4 you may need to transcode or rely on the engine's bundled WebM/MP4 plugin. Studio's import pipeline handles transcoding when the path extension is set explicitly — confirm the resulting resource type with summer_inspect_resource if playback fails.

summer_add_node(parent="./TitleScreen", type="VideoStreamPlayer", name="BackgroundLoop")
summer_set_prop(path="./TitleScreen/BackgroundLoop", property="stream", value="res://assets/video/loops/title_screen_bg.ogv")
summer_set_prop(path="./TitleScreen/BackgroundLoop", property="autoplay", value=true)
summer_set_prop(path="./TitleScreen/BackgroundLoop", property="loop", value=true)
summer_set_prop(path="./TitleScreen/BackgroundLoop", property="expand", value=true)
summer_set_prop(path="./TitleScreen/BackgroundLoop", property="anchors_preset", value=15)

Anchors preset 15 is "full rect" — the loop fills the menu. Place the logo and menu buttons as children above the VideoStreamPlayer in the tree (Godot draws siblings in tree order; later siblings render on top).

7. Mute the audio track

Loops should never have a baked audio track that loops with them — the audio seam will be even more obvious than the visual one. The video models don't generate audio anyway, but if you ever import a clip that has audio, mute it:

summer_set_prop(path="./TitleScreen/BackgroundLoop", property="volume_db", value=-80)

Score the menu separately with audio/music-track.

Reference card — prompts that work

Pattern: <subject> + <ambient loopable motion> + <constant lighting> + "looping, seamless" + <stylistic anchor>. Keep under 40 words. Always pair with imageUrl.

Goal	Model	Prompt	Cost	Duration
Title menu — fog forest	ltx	dense pine forest in low fog, fog drifting slowly between trunks, soft moonlight, ambient particles rising, looping, seamless, cinematic painterly	$0.10	4s
Title menu — dungeon torch	ltx	stone dungeon corridor lit by a single torch, flame flickering steadily, dust motes drifting in the light cone, looping, seamless	$0.10	4s
Splash — embers / sky	ltx	dusk sky with slow drifting embers rising upward across frame, deep blue gradient, looping, seamless, cinematic	$0.10	5s
Logo backdrop — magic runes	ltx	dark surface with glowing blue runes pulsing softly in slow rhythm, faint shimmer, no narrative motion, looping, seamless	$0.10	3s
Menu — underwater	ltx	underwater scene with caustic light dancing on a sandy floor, slow drifting bubbles, gentle current sway on kelp, looping, seamless	$0.10	5s
Pause screen — slow rain	ltx	window pane with continuous gentle rain drops, blurred warm interior glow behind, looping, seamless, ambient	$0.10	4s
Title — anime sky	minimax	anime style cumulus clouds drifting slowly across a pastel sunset sky, soft, painterly, looping, seamless, Ghibli	$0.40	4s
Premium splash centerpiece	kling	dragon silhouette breathing in profile against a vast sunset sky, only the chest rising and falling and clouds drifting, looping, seamless	$0.50	5s

Bad prompts and why

Bad	Why it fails
looping background of a hero walking through a forest	"Walking" is non-loopable — the hero arrives and departs. Replace with forest with fog drifting.
dramatic title screen video	"Dramatic" implies narrative beats; loops want ambient. Specify the ambient motion.
make it 10 seconds and loop	10s loops show their seam. Drop to 5s.
epic looping background trending on artstation	Adjective slop. The model already knows "cinematic"; the rest hurts.
the door slowly opens, looping	Doors don't loop — they open once. The clip will hard-cut on replay.

Anti-patterns

• Asking the model for a 10s loop. Past ~6s, identity drifts and the seam shows. Cap at 5s.
• Spending kling money on a loop. ltx is the right call ~95% of the time. The constraints favor the cheap model.
• Prompting narrative motion. "Hero draws sword" doesn't loop. Use ambient verbs.
• Forgetting loop=true on the VideoStreamPlayer. The clip will play once and freeze on the last frame.
• Forgetting to mute baked audio. If audio is on, the loop point becomes audible even if it's invisible.
• Using aspectRatio="16:9" for a portrait splash. Pillarboxed loops on a vertical splash look broken. Set 9:16 and frame portrait.
• Importing without transcoding to a Godot-friendly container. VideoStreamPlayer natively wants Ogg Theora; .mp4 works with the bundled plugin but isn't guaranteed across platforms — confirm with summer_inspect_resource.

Edge cases

• Splash loop must be tiny in build size. Loops compress aggressively because of low motion. Target ≤2MB by exporting at 720p, low bitrate, in DaVinci. Studio's import doesn't re-encode by default.
• Mobile portrait splash. aspectRatio="9:16", reference image at portrait, anchors preset 15 still works.
• Loop must sync to a music beat. The video model doesn't know your BPM. Generate at the duration matching one bar at the menu music tempo (e.g. 120 BPM × 4 beats = 2s, or 8 beats = 4s) and confirm visually.
• Loop is behind translucent UI. Generate with extra contrast headroom — the model tends toward mid-grey, and translucent UI on mid-grey reads muddy. Push for high contrast cinematic in the prompt.
• Loop seam still visible after 3 regens. Set up two VideoStreamPlayer siblings and crossfade between them with a Tween on a 0.5s overlap. Costs an extra GPU decode but hides the seam.

Fallback (no MCP)

If the Studio MCP server isn't running, route the user to the Studio web dashboard:

1. Image tab → generate the reference still (the loop's "neutral frame").
2. Video tab → image-to-video with ltx, duration 4s, aspect ratio per target.
3. Prompt with the loopable-motion vocabulary above and "looping, seamless".
4. Download the result, transcode to .ogv if needed, place under assets/video/loops/.

Print the exact prompt + model + duration + aspect ratio so the user can paste it into the dashboard.

Handoff

Once the loop is wired:

Loop title_screen_bg is wired to TitleScreen/BackgroundLoop with autoplay + loop. Next:

• Score the menu with audio/music-track — a quiet ambient bed scored to the loop's mood.
• For the logo and menu UI on top, hand off to 2d-assets/ui-graphics.
• If the user wants a punchy 5s shot for the trailer using the same look, hand off to video/trailer-shot (reuse the reference image).
• If the user wants a narrative intro that plays before the title loops, hand off to video/cinematic-cutscene.

See also

• video/trailer-shot — punchy marketing footage.
• video/cinematic-cutscene — narrative cutscenes with dialogue.
• audio/music-track — score the menu.
• 2d-assets/ui-graphics — logo, menu buttons, HUD that sits over the loop.
• 2d-assets/concept-art — produce the reference still that anchors the loop.
• references/mcp-tools-reference.md — summer_generate_video parameter schema and error codes.