3D Map Explainer — our demo

One example among many. Don't reuse its story, arc, shots, props or timings.

Demo: Strait of Hormuz 《霍爾木茲海峽》 (52.0 s) · map-explainer.mp4 · source in demo/

Why does about a fifth of the world's oil have to squeeze through one strait, and why can't it go around? The film falls from space into the Persian Gulf, measures the strait, cuts the sea open to show its depth, flies along the shipping lanes, grows the daily flow as a pillar, draws the two bypass pipelines across Arabia, sets their spare capacity next to the flow on the same scale, and climbs back to the globe where the routes to Asia light up. English narration (Kokoro bm_george) with Chinese and English subtitles. Every number is sourced in demo/FACTS.md; routes and pipeline paths are schematic and say so on screen.

Story & structure

Question: why this place? Three contrasts: the volume is huge (20 million barrels a day), the way is narrow (21 nautical miles at the narrowest, two lanes of 2 miles each), the alternatives are small (2.6 to 5.5 million barrels a day of spare pipeline capacity, two estimates). Landing: for most of this oil there is no other way out, and most of it is bound for Asia; the film ends on the globe it started from, now with meaning in its lines.

Candidate structures considered: following one tanker from a terminal to Asia (a hero, but a ship barely moves in 50 s and the shape of the gulf is lost) and three numbers in three chapters (clear but slide-like). The funnel won because the signature, real terrain with a glowing data layer, can go one step further each time: flow → structure → depth → width → volume → alternatives → the world.

Native moves spent: the dive from orbit, flows converge, a line ignites along its true course, cut the map open, fly the line, quantities on the ground, back to the world.

Shots

Film time, 24 fps, 96 bpm (one bar = 2.5 s).

# Time Shot Camera / transition Native move / note
S1 0.0–6.4 The Earth at night's edge, the terminator over Asia; a dim amber point at the strait with faint routes leaving it; from 2.1 a ring pulse and a leader line out to the title STRAIT OF HORMUZ / 霍爾木茲海峽, set in the dark Arabian Sea push from 26,000 km to ~1,200 km the globe carries the region's imagery so the dive matches
— 5.6–6.4 Dissolve through the atmosphere: the globe camera is computed from the map camera; a faint warm layer peaks halfway dissolve
S2 6.4–10.6 The Persian Gulf in 3D relief; seven oil terminals light up west to east, their routes grow and pour into one trunk line flowing to the strait; country and sea names the dive continues, pitch 79° → 52° flows converge
S3 10.6–15.0 The strait: the narrowest line grows between Larak Island and Great Quoin Island, NARROWEST POINT · 21 NM · 39 KM; at 12.5 (bar 6) both lanes ignite from opposite ends, dashed boundaries follow, the first ships enter levels out, near-locked a line ignites
S4 15.0–20.0 The camera orbits to the west of the measured line and drops to sea level; at 15.7 the west half of the map is swept away and the section wall stands: Iran's shore, Larak, both lanes marked on the surface with dashed soundings to the floor (≈ 80 m), the deeper trench to the south; caption SECTION · NARROWEST LINE / DEEP ENOUGH FOR THE LARGEST TANKERS / WATER DEPTH ×150 · LAND ×3.2, a 0–50–100 m scale orbit + crane down; the cut cut the map open
S5 20.0–24.6 The film's only hard cut, on the downbeat of bar 9: at sea level, flying west along the inbound lane, passing tankers, others coming the other way; a ruler across both lanes: INBOUND · 2 NM / BUFFER · 2 NM / OUTBOUND · 2 NM low tracking shot, shallow focus fly the line
S6a 24.6–29.6 The camera rises and turns to the strait; from 25.9 a pillar grows in the separation zone, one slab per million barrels a day, 20 slabs, labelled 20 MILLION BARRELS A DAY · 2024 AVERAGE · EIA crane up + orbit quantities on the ground
S6b 29.6–34.0 One pull-out to ~2,400 km: all of Arabia; the East–West pipeline draws from Abqaiq to Yanbu on the Red Sea, the Habshan–Fujairah line to the Gulf of Oman; cased amber lines, end points named big pull-out
S6c 34.0–40.4 The camera swings to the north side of the strait and sees it square-on: three pillars on open water, one scale: 20 (amber, EIA), 2.6 (teal, EIA estimate of spare pipeline capacity), 3.5 solid + lighter teal to 5.5 (IEA estimate); 70 px numbers over each; SPARE CAPACITY TO BYPASS THE STRAIT above them; the whole group in frame and held ≈ 2.6 s with every label swing + push, then a slow drift the verdict frame
— 40.0–40.8 The map rises and dissolves back to the globe dissolve
S7 40.4–52.0 The globe turns east; routes to India, China, Japan and South Korea light up bright, Europe stays dim; the frame shifts left; 84% / OF THE CRUDE OIL THROUGH HORMUZ / WENT TO ASIA IN 2024 · EIA on the right; from 48.6 the end card takes its place pull-back + view offset back to the world

Score structure

D minor, 96 bpm, 20 bars plus the end card; the voice owns the mids.

Voice: Kokoro bm_george, speed 0.74–0.84, ten lines (demo/voice/lines.json), every line passing asr_check.py (homophones such as strait/straight carry an asr field). Numbers are spelled out in the voice text and written as digits in the subtitles (demo/voice/subs.json → demo/voice/cues.json).

Palette & props

End card

In the empty sky to the right of the globe, set like a chart's title block: a north arrow and an amber rule, STRAIT OF HORMUZ (54 px) / 霍爾木茲海峽 (36 px), a hairline, 3D MAP EXPLAINER 立體地圖解說, and "LemoLab × Claude Opus 5.5" (30 px). It arrives 48.6–49.0 s (the 84% steps aside 48.3–48.7) and holds to 52.0 s, clear of the subtitles at the bottom left. The "LemoLab × Claude Opus 5.5" sign-off belongs to this library's demo only; a user's film carries no LemoLab credit and no copy of this card.

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