skills/krea-motion/references/dimensional-motion.md

# Dimensional Motion — Air, Orbit, Depth, And 3D

Everything that happens **off the ground and around the object**: levitation,
mid-air choreography, orbits and rotations, exploded views, macro dives into
detail, and camera work over CGI and architectural renders.

This is where Seedance is at its strongest and where the difference between a
prompt that respects physics and one that doesn't is most visible. The whole
discipline reduces to one sentence: **weightlessness must look deliberate, not
accidental.** An object suspended on purpose reads as engineered and expensive.
The same object drifting a few centimeters unbidden reads as a glitch.

---

## Part 1 — Levitation And Suspension

### The Two Failure Modes

1. **Floaty.** The object bobs, sways, wanders, slowly tumbles. Caused by the
   absence of an explicit lock and by pace adverbs like `gently floating`.
2. **Weightless-but-fake.** The object hangs but nothing else acknowledges it —
   no cast shadow beneath, no reflection, no ground plane relationship. The eye
   reads it as a pasted layer.

### The Suspension Lock

Use this block, near-verbatim, for any levitating subject:

```
The object is suspended in mid-air, absolutely level and absolutely still — it
does not bob, sway, wobble, tumble, drift, or change scale. It holds one fixed
position in space for the entire shot. A soft contact shadow sits on the surface
directly below it, confirming its height. Realtime physics; no floating drift,
no slow-motion.
```

That last clause matters: *suspended* and *floating* are different instructions.
"Suspended" gets you a held position. "Floating" gets you drift.

### Controlled Rise

When the object should gain altitude, quantify it exactly.

```
SHOT 1 — RISE (0–4s), medium, 85mm. Camera locked. The object lifts 12 centimeters
straight up across 4 seconds at a perfectly constant rate, dead level, no rotation,
no sway, no acceleration. Its contact shadow beneath softens and spreads as it
rises. It stops dead at the top of the move and holds.
```

The shadow behaviour is the tell that makes levitation read as real. Always
include it: `the contact shadow softens and spreads as it rises` (or `sharpens and
contracts as it descends`).

### Suspended With A Moving Camera

The premium hero configuration: object frozen in air, camera doing all the work.

```
Motion split: the object is suspended and completely locked — zero rotation, zero
drift, zero scale change. ALL movement in this shot belongs to the camera. Dust
motes and the travelling specular move at realtime speed. Nothing is speed-ramped.

SHOT 1 — SUSPENDED PUSH (0–6s), medium close, 85mm. One continuous push-in of
roughly 20 centimeters across the full 6 seconds, dead level, motion-control
smooth. The suspended object holds absolutely still as the frame closes on it.
```

### Mid-Air Choreography (Multiple Objects)

Several objects in the air need **named paths**, or they will interpenetrate and
swap depth.

```
SHOT 2 — AIR ARRAY (2.5–5.5s), medium wide, 50mm. Camera locked. Three components
hang suspended at three different depths — the base nearest camera at lower-left,
the body center at mid-depth, the cap furthest at upper-right. Each holds its own
fixed position; they never touch, never cross, never swap depth. Over 3 seconds
each rotates in place exactly 20 degrees about its own vertical axis at a constant
rate, all in the same direction. No bobbing. Realtime speed.
```

Rules for multi-object air work:

- Give every object a **screen position** and a **depth**.
- State `they never touch, never cross, never swap depth`.
- Give each one **at most one** motion, and make it identical in kind across
  objects — same axis, same direction, same rate. Divergent motions read as chaos.
- Cap it at three or four objects. More becomes soup at any duration Seedance offers.

### Weightless Orbit Of Elements Around A Hero

```
SHOT 2 — SATELLITES (2.5–6s), medium, 50mm. The hero object is suspended dead
center and completely locked. Four small elements orbit it in one shared
horizontal plane, all traveling in the same direction at the same constant rate,
completing a quarter turn over 3.5 seconds. They pass behind the hero and are
correctly occluded by it. They never touch it and never touch each other.
Camera locked.
```

The occlusion clause — `pass behind the hero and are correctly occluded by it` —
is what forces real depth rather than a flat overlay.

---

## Part 2 — Rotation And Orbit

### Object Rotation vs Camera Orbit

These are different shots and users conflate them. Decide, then say which.

- **Object rotation** — the object turns, the camera holds. Reads as a product
  turntable: clean, catalog, honest.
- **Camera orbit** — the object holds, the camera arcs around it. Reads as
  cinematic: the viewer is moving, which is inherently more expensive-looking.

**Prefer camera orbit for hero work.** Object rotation is for disclosure ("show me
all sides"), camera orbit is for drama.

### Camera Orbit, Written Properly

```
SHOT 2 — ORBIT (2.5–6.5s), medium close, 85mm. The camera arcs 45 degrees to the
right around the object in one continuous move across 4 seconds, staying at a
constant radius and constant height, dead level — a motion-control orbit, no
handheld, no bob, no dolly-in during the arc. The object is locked and does not
rotate. As the camera travels, the specular highlight sweeps along the chamfer and
the far side of the mark comes into view.
```

Load-bearing details: **degrees of arc**, **direction**, **constant radius**,
**constant height**, and the explicit statement that the object is *not* rotating.

Arc budget: 30–60 degrees over 4 seconds is elegant. 180 degrees in 4 seconds is a
music video. A full 360 needs the whole duration and usually costs you the ability
to do anything else in the shot.

### Object Turntable, Written Properly

```
SHOT 2 — TURNTABLE (2.5–6.5s), medium, 85mm. Camera locked absolutely still. The
object rotates in place exactly 90 degrees clockwise about its own vertical axis
across 4 seconds at a perfectly constant rate — no wobble, no axis tilt, no
vertical drift, no scale change. The rotation is mechanically smooth, like a
precision turntable. Realtime speed, no slow-motion.
```

`about its own vertical axis` prevents the tumble. `no axis tilt` prevents the
gradual lean that otherwise creeps in.

### Reveal-By-Rotation

Rotation as a disclosure mechanism, which is what makes it a *shot* rather than a
turntable render:

```
The object rotates 100 degrees across 4 seconds; the engraved mark, hidden on the
far side at the start, travels into full view and is razor sharp and centered
exactly at the end of the move. The rotation stops dead there and holds.
```

Naming *what the rotation discloses and when* is the difference between a spin and
a reveal.

---

## Part 3 — Exploded Views And Deconstruction

The most impressive mid-air showcase Seedance does, and it lives or dies on the
words *maintaining shape and scale*.

### Explode

```
SHOT 2 — EXPLODE (2.5–6s), medium wide, 50mm. Camera locked. The object separates
into its five components, which travel outward along straight radial paths and stop
dead, each holding suspended in mid-air at its own depth in a clean symmetrical
array. Every component keeps its exact shape, scale, material and orientation
throughout — no morphing, no melting, no deformation, no scale change, nothing new
appears. The separation happens at realtime speed and completes by 5s; the array
then holds absolutely still. Correct depth occlusion between components.
```

Non-negotiable clauses:

- `keeps its exact shape, scale, material and orientation`
- `no morphing, no melting, no deformation`
- `nothing new appears` — otherwise Seedance invents parts
- `stop dead` and `holds absolutely still` — otherwise the array keeps drifting
- `correct depth occlusion`

### Reassemble

The reverse, and it reads even better as a reveal because it resolves.

```
SHOT 3 — REASSEMBLE (6–10s), medium, 50mm. Camera locked. The five suspended
components travel back inward along their original straight paths and seat into
one another in sequence — base at 7s, body at 8s, collar at 9s, cap at 9.6s —
each stopping dead on contact with no bounce and no overshoot. The completed object
holds suspended, absolutely still, for the final half second. Every component keeps
its exact shape and scale throughout.
```

### Cross-Section / Cutaway

For mechanism and material storytelling.

```
SHOT 3 — CUTAWAY (6–9s), medium close, 85mm. Camera locked. A clean vertical plane
passes through the object and the near half becomes fully transparent, disclosing
the internal structure in cross-section with hard clean cut edges. The object does
not move, rotate or change scale. The internal geometry is lit by the same single
source. No exploded parts, no labels, no on-screen text.
```

---

## Part 4 — Macro Dives And Detail Exposure

"Zoom in on the details to expose them" — one of the most requested and most
frequently botched moves. Botched because people write it as a zoom instead of as a
**journey to a destination**.

### The Macro Dive

```
SHOT 2 — DETAIL DIVE (2.5–6s), medium close opening to extreme macro, 100mm macro.
One single continuous push-in across 4 seconds, traveling from the full object down
to a 3-centimeter field of view centered on the engraved mark. The focus plane
travels with the camera so the mark is razor sharp at the end of the move; the
surround falls entirely to bokeh. Constant rate, dead level, no rotation, no
searching. The object is locked. The camera stops dead on the detail and holds for
the final half second.
```

What makes this work:

- **Name the destination**: not "zoom in on the details" but *"a 3-centimeter field
  of view centered on the engraved mark"*.
- **Couple focus to the move**: `the focus plane travels with the camera` — else you
  arrive out of focus.
- **Say `no searching`**: prevents the little hunting adjustments that read as
  amateur.
- **Stop dead and hold**: the arrival is the payoff.

### Macro Surface Traverse

A lateral move across texture. Reads as material study, gorgeous at 21:9.

```
SHOT 3 — SURFACE TRAVERSE (6–9s), extreme macro, 100mm macro. The camera tracks
laterally 4 centimeters across the surface over 3 seconds at a constant rate, dead
level and parallel to the surface. Brushed grain, micro-scratches and dust
particles pass through the shallow focus plane; the specular streak stretches along
the grain as the camera travels. The object is locked. Realtime speed.
```

### Pull-Out From Macro

The inverse — abstraction resolving into recognition. A superb opener.

```
SHOT 1 — MACRO OUT (0–4s), extreme macro opening to medium, 100mm to 50mm. We open
on an abstract lit texture with no readable context. One continuous pull back
across 4 seconds; the form resolves, the whole object assembles in frame, and the
camera stops dead on a composed medium with the object on the lower third.
```

### Detail Beat Chaining

Three details in one generation, each a real cut:

```
SHOT 2 — DETAIL A (2.5–4s), extreme macro, 100mm. Locked on the engraved mark; a
specular crosses it left to right. Cut on the highlight.
SHOT 3 — DETAIL B (4–5.5s), extreme macro, 100mm. Locked on the machined seam; the
same specular direction continues across it. Hard cut.
SHOT 4 — DETAIL C (5.5–7s), extreme macro, 100mm. Locked on the material grain,
focus resolving from soft to sharp across the beat. Punch-in cut.
```

Carrying the highlight direction across the cuts is what makes three unrelated
macros read as one deliberate sequence.

---

## Part 5 — 3D Renders, CGI, And Architectural Work

Seedance animates a still render better than almost anything else available, and
the discipline is different from photographic work: the render is already perfect,
so your only job is to add **camera and light** without letting the model
re-interpret the geometry.

### The Geometry Lock

Every render-animation prompt needs this:

```
The geometry, materials, textures, layout and proportions of @Image1 are fixed and
must not change — no elements are added, removed, moved, resized or restyled. Only
the camera and the light move. No morphing, no new objects, no re-modelling.
```

Without it, Seedance treats a render as a suggestion and starts redesigning
furniture, adding windows, or drifting a facade line.

### Architectural Flythrough

```
Format: Architectural film, 8 seconds, 21:9, natural-light photoreal, no text.
References: @Image1 as the first frame — the approved render; geometry, materials
and layout are fixed exactly as shown.
Consistent world: single-source daylight from the existing window direction,
neutral white balance, the render's own palette.
Motion split: the building and every object in it are completely static. All
movement belongs to the camera. Only atmospherics move — fine dust in the light
shaft and the faintest leaf movement outside — at realtime speed.

SHOT 1 — APPROACH (0–4s), wide, 24mm. One continuous forward dolly of roughly 1.5
meters across 4 seconds, dead level, at a constant rate — architectural-camera
smooth, no handheld, no bob, no roll. Parallax reveals the depth of the space as
foreground edges pass. Hard cut.
SHOT 2 — DETAIL (4–8s), medium close, 85mm. Camera locked. Daylight shifts across
the material surface, a hard shadow edge traveling 15 centimeters over 4 seconds.
Nothing physical moves. The camera holds still and the frame settles.

Light: single daylight source through the existing opening; NO god rays, NO light
beams, NO lens flare, NO bloom, NO blue grade.
Audio: no music; only faint room tone.
Constraints (reassert): geometry and materials fixed exactly as @Image1, nothing
added or moved; camera-only motion, constant rate, architectural smooth; realtime
atmospherics, no speed ramping; no people appearing, no text, no graphics, no
god rays, no flare.
```

For the still-render *production* side — generating the render from a 3D or CAD
screenshot in the first place — route to
`../../krea-generate/workflows/archviz-3d-to-render.md`, then animate the approved
still here.

### CGI Object Motion

For stylized or hard-surface CGI where the render look must survive:

```
Motion split: the model is locked — no deformation, no topology change, no
material change. Camera and light only. Any procedural surface behaviour named
below moves at realtime speed.
...
Constraints (reassert): CGI render look preserved exactly — same shader response,
same material, same edge quality as @Image1; no photoreal conversion, no added
grain, no re-lighting beyond the named source; no morphing.
```

That last clause matters: Seedance will drift a stylized render toward
photorealism unless told not to.

### Turntable Product Render

The clean catalog version, worth having in the toolkit:

```
Format: Product turntable, 6 seconds, 1:1, clean high-key studio, no text.
References: @Image1 as the first frame and the product; geometry, materials and
printed lines fixed exactly as shown, never re-lettered.
Consistent world: bone-white seamless, soft shadowless light, one thin contact
shadow directly beneath, no gradient, no vignette.
Motion split: camera locked absolutely still. The product rotates in place exactly
180 degrees clockwise about its own vertical axis across the full 6 seconds at a
perfectly constant rate — no wobble, no axis tilt, no vertical drift, no scale
change. Realtime speed.
Light: soft overhead source, even, shadowless except the contact shadow; NO flare,
NO bloom, NO gradient background, NO blue cast.
Audio: silent.
Constraints (reassert): single constant-rate rotation, mechanically smooth; product
and printed text exactly as @Image1; white seamless holds throughout; no camera
movement, no zoom, no extra objects, no text overlay.
```

---

## Part 6 — Selecting The Dimensional Move

| Intent | Move |
|---|---|
| "Make it hero / important" | Suspension lock, cut between two or three angles on it, then pull out to the whole |
| "Show all sides" | Object turntable, constant rate, named degrees |
| "Make it cinematic while showing sides" | Camera orbit 45° at constant radius |
| "Show what's inside / how it's built" | Explode → hold → reassemble, or cutaway |
| "Zoom into the detail" | Macro dive with named destination and coupled focus |
| "Show the texture / material" | Macro surface traverse |
| "Reveal what it is" | Pull-out from macro |
| "Fly through the space" | Architectural approach dolly with geometry lock |
| "Float it / put it in the air" | Suspension lock + controlled rise + shadow behaviour |
| "Have parts orbit around it" | Satellite orbit with occlusion clause |

## The Dimensional Checklist

Before submitting any air, orbit, or depth shot:

- [ ] Is the subject explicitly **locked**, or is its motion explicitly **named and
      quantified**? (Never neither, never both.)
- [ ] Does every camera move have a **distance or degree count** and a **duration**?
- [ ] Is there exactly **one** camera move in each beat?
- [ ] For levitation: is the **contact shadow** behaviour described?
- [ ] For multi-object air: are **depths**, **screen positions** and
      `never touch, never cross, never swap depth` all present?
- [ ] For explode/assemble: are `exact shape and scale`, `no morphing`,
      `nothing new appears`, and `stop dead` all present?
- [ ] For macro: is there a **named destination** and is focus **coupled to the
      move**?
- [ ] For renders: is the **geometry lock** present?
- [ ] Is `realtime physics, no speed ramping, no slow-motion` in the motion split
      **and** the constraints tail?