/fly Cinematic Shot Language — Guide for Polish Waves

Compiled 2026-06-10 to gate the next /fly polish wave (post v0.7 Cassini hero-shot pass). Reference principles for camera, composition, light, and pacing on the /fly route. Quote in polish PRs and code review. The meta-rule below is the standing test: every choice serves it.

Meta-rule: make the viewer feel small in the presence of something ancient and large. Real spacecraft, real trajectories, real geometry — the discipline is to frame that genuine substance the way Cassini's "Day the Earth Smiled," Cowboy Bebop's Jupiter Gate, Planetes' wrench drift, and 2001's docking sequence in silence all do it.

---

Principles (the rules that don't change)

P1. Space is dark, not black

A pure #000 sky is the #1 amateur-CG tell. Real deep-space photography has structure: zodiacal light, galactic plane gradient, stellar parallax dust. Use a faint warm-cool gradient + sparse stars + a Milky Way hint. Cowboy Bebop paints this; JPL Eyes On bakes it as a cubemap.

P2. One hard light, one soft fill, nothing else

The Sun is one source. Bounce comes from planet albedo lighting the shadow side. Two-key-light setups read as studio product CG. Sun direction must be consistent across foreground, midground, background.

P3. The silhouette test

At 64×64 black-on-white, the spacecraft + planet + motion vector must still be readable. NASA mission art passes this; the Cassini-Saturn hero shot is recognizable at thumbnail size. Composition that fails silhouette cannot be saved with shading.

P4. Three layers of depth, minimum

Foreground (spacecraft, antenna, instrument) / midground (the body being approached, its rings, its moons) / background (star field, distant Sun, distant other body). Two layers feels like a screensaver. Galileo-Jupiter shots always include Io or Europa as midground anchor.

P5. Scale is communicated by reference, not size

You don't feel Jupiter's scale by rendering Jupiter. You feel it when a 10-pixel spacecraft hangs against a limb that fills 80% of frame and the limb is still curving out of view. Containment kills awe; let the limb arc out of frame.

P6. Motion has weight when camera disagrees with subject

Interstellar's Endurance moves slowly; the camera drifts in a parallax arc disagreeing with the ship's motion vector — reads as massive. Camera locked-rigid to the ship reads as a toy on a string.

P7. Logarithmic time around mission events

Closest-approach is 90 seconds in real life. Cinema stretches it to 30 seconds of screen time. The cruise weeks compress to 3 seconds. Music, sound, and camera moves all stretch in and contract out.

---

Tactics (Three.js implementations)

T1. CameraRig abstraction

Build a rig object: { target, lookAtOffset, boomLength, boomYaw, boomPitch, fov }. Animate the rig, not the camera directly. Enables:

• Parallax tilts — animate boomYaw while target locked
• Dolly push — animate boomLength while fov holds
• Focal-length zoom — animate fov while boomLength holds (gives JPL's "telephoto compression" feel — flattens depth, more cinematic)

Default FOV: 40–55° vertical for cruise (~35–50mm equiv), 15–25° for hero close-ups (~85–135mm equiv). The telephoto end is what makes JPL renders read as massive.

T2. Rule of thirds

Spacecraft on the left or right vertical third, never centred. Planet limb arcs through opposite third + bottom edge. Stars and Sun occupy the diagonal negative space. Implement as a runtime invariant during cinema phase: assert spacecraft screen-X is in [0.30, 0.40] or [0.60, 0.70]; nudge boomYaw if outside.

T3. Limb-grazing pass

Closest-approach window: constrain camera so planet limb is tangent to one screen third. Place planet center off-frame such that the limb crosses the vertical third line. Spacecraft grazes within 5–10% of viewport-width from the limb. This is the Cassini-Saturn hero composition.

T4. Asymmetric Freytag flyby pacing

Replace the symmetric "25 days before / 25 days after" with a 3-stage pyramid:

Stage	Window	Camera	FOV	On screen
Approach	T−25d → T−5d	Slow dolly-in, boom shrinks 30%	45° → 30°	Planet grows midground → limb-filling; ship tiny lower-third
Peak	T−5d → T+2d	Boom yaw arcs 60–90°, parallax around ship	30° → 18°	Limb-grazing; ship hero, planet silhouette wall
Departure	T+2d → T+25d	Long slow pull-out, FOV widens	18° → 50°	Ship recedes; melancholy register

Departure should be 3–4× longer in screen-time than approach. The "afterglow beat" 99% of amateur sims skip — JPL Cassini end-of-mission lingers ten beats after the burn.

T5. Lighting rig

DirectionalLight (Sun) — intensity 3–5 (PBR), color #fff4e8, castShadow
HemisphereLight — sky #08101a, ground #000, intensity 0.05–0.10
AmbientLight — DO NOT USE

Add a planet-bounce light on the spacecraft only: a second DirectionalLight pointing from planet → spacecraft, intensity scaled by (planet_albedo / dist²), color tinted by the planet body (warm for Jupiter/Saturn, cool blue for Neptune/Uranus, ochre for Mars).

T6. Rim light from the limb

When spacecraft is in the cinema window AND between Sun and planet, add a Fresnel-based rim shader on the spacecraft material — brightens grazing-angle pixels with a warm tint. In Three.js: MeshStandardMaterial with onBeforeCompile fresnel injection, or a separate ShaderMaterial pass. #1 visual signature of cinematic spacecraft.

T7. Post-processing stack

Use EffectComposer with this order:

1. RenderPass — base scene
2. UnrealBloomPass — radius 0.4–0.6, threshold 0.85, strength 0.3–0.5. Sun + plumes bloom; planets do not (clamp HDR).
3. BokehPass — focal distance = ship distance, aperture 0.0001–0.0005, max blur 0.005. Subtle. Stars just slightly defocused.
4. FilmPass (or custom grain) — noise 0.05–0.10. Below conscious perception but above zero. More impact than any other post effect.
5. VignettePass — offset 1.0, darkness 0.6.
6. THREE.ACESFilmicToneMapping on renderer; toneMappingExposure 1.0–1.2. Single most important line for cinematic feel — HDR Sun → SDR display.

T8. Skydome with structure

Replace solid-black with a cubemap skydome: sparse star field (Hipparcos- weighted magnitudes), faint Milky Way band, near-imperceptible warm gradient toward ecliptic. Lazy-load — stub starfield on initial paint, promote to full skydome on first cinema frame.

T9. Particle dust

50–200 sparse particles (≤2 px), additive blend, lit by Sun, emitted along ship motion vector during cinema. Conveys velocity. Dense particles read as snow — keep sparse.

T10. Lens flare — almost never

Only when Sun is in frame AND deliberately invoking "spacecraft camera POV." Single subtle anamorphic streak, not a JJ-Abrams light show. Tune Three.js Lensflare addon to ≤30% default intensity.

T11. Engine plume glow

During burn events (TCM, capture, departure): billboarded sprite, additive blend, soft-falloff radial gradient, tinted by propellant chemistry (blue-white hypergolic, orange solid, faint blue ion). Intensity from burn-magnitude data. The mission-art leitmotif: small orange spark against planet limb.

T12. Performance budget

60fps on 2020 MacBook Air → 16.6ms/frame.

• Scene render ≤8ms
• Bloom ≤2ms (half-res)
• DoF ≤2ms (quarter-res CoC)
• Tonemap + grain + vignette ≤1ms
• Headroom 3.6ms

Drop DoF first on mobile. Drop bloom radius next. Never drop tonemapping — costs almost nothing, provides almost everything.

---

The Checklist (a shot ships when it passes all 8)

1. Silhouette test — readable at 64×64 black-on-white?
2. Three-layer test — foreground / midground / background each at distinct depth?
3. Limb-rim test — planet limb arcs across one screen-third with spacecraft silhouetted against it (at least one shot per flyby)?
4. Single-source-light test — every lit pixel consistent with one Sun position? No second key, no flat ambient?
5. Negative-space test — ≥30% of frame is "empty" deep space?
6. Camera-disagree test — camera doing something the ship is not (parallax / dolly / FOV breath)?
7. Scale-reference test — second body (moon, ring, distant planet) in frame, OR limb gracefully exits frame?
8. Logarithmic-pacing test — closest-approach has more screen-seconds than equal-time cruise? Departure ≥3× approach in screen time?

---

Anti-patterns

• Pure #000 sky
• Whole planet centred, fitting frame (wallpaper feel)
• Ambient light flattening shadow contrast
• Two key lights (product-render feel)
• Camera locked to ship's motion (toy-on-string feel)
• Symmetric flyby timing (departure = approach = boring)
• No post-processing stack (raw WebGL = cutscene feel)
• Lens flare every frame
• Oversaturated planet textures
• Spacecraft fully lit with no rim
• Single FOV across cruise + flyby
• Dense particle effects (snow feel)
• Centred spacecraft on every frame
• Music-less hold shots <2 seconds (the hero pull-out wants 5–8)

---

Reference set

• NASA/JPL Eyes On Solar System (open source at github.com/nasa)
• NASA mission art prints: Cassini-Saturn, Galileo-Jupiter, Pioneer 10/11, Juno-Jupiter, Europa Clipper concepts
• Cowboy Bebop ep. 5 — Jupiter approach sequence
• Planetes — OP + EVA sequences
• Interstella 5555 — Daft Punk / Toei, sci-fi composition rules
• 2001: A Space Odyssey — docking, opening
• Interstellar — Endurance shots (Double Negative VFX breakdowns document the camera-disagree principle)
• Cassini Imaging Team (Space Science Institute) — limb-grazing photos
• Wired magazine — Cassini end-of-mission illustrations
• Three.js postprocessing community examples