Blender shots

Real product shots from a 3D model: the recipe, the four kinds, the stills judged first, and the clips with alpha a scene plays.

A rapid shot is a model and a recipe, rendered by Blender as frames with a transparent ground, so a scene can place the product over any field. A recipe is data, like a style. When a storyboard lists shots, the job renders them before the scenes that show them are built.

You need Blender, and only for a video that plans a shot. rapid runs /Applications/Blender.app, or the binary in RAPID_BLENDER. rapid setup --check doesn't look for it, so a missing Blender first shows as a failed node or command.

A recipe

Put the model under assets/ (STL, OBJ, or GLB) and write the recipe as shots/<id>.json:

{
  "schema_version": 1,
  "id": "pendant",
  "kind": "turntable",
  "model": "assets/pendant.stl",
  "size": 0.03,
  "frames": 90,
  "fps": 30,
  "width": 1080,
  "height": 1080,
  "engine": "cycles",
  "finish": "mirror",
  "metal": "#D9D4CC"
}

width and height are the size the shot sits at in the frame, not the frame's. frames at the format's rate covers the scenes that show it.

Field	Type	Default	Notes
`schema_version`	`1`	required
`id`	id	required	names `renders/shots/<id>/`
`kind`	`turntable`, `clay-metal`, `macro`, `build`	required
`model`	path	required	in the project
`frames`	1–3600	required
`width`, `height`	1–4096	required
`fps`	1–120	`30`
`size`	metres, up to 10	`0.03`	the piece's real longest side; it scales the aperture, focus, and shadows
`engine`	`eevee`, `cycles`	`eevee`	EEVEE takes a fraction of a second a frame; Cycles is for hero metal and glass
`lean`	degrees, −90 to 90	`6`	how far the piece leans back: about 6 for a small pendant, about 40 for a long chain
`camera.elevation`	degrees, −60 to 80	`12`	the camera's height above the piece
`camera.lens`	mm, 10–300	`100`
`fill`	0.1–1	`0.76`	how much of the frame the piece fills at its widest
`finish`	`satin`, `mirror`	`satin`	satin for organic sculpts, mirror for faceted ones
`metal`	`#rrggbb`	`#D9D4CC`
`turns`	up to 10	`1`	turns over the clip
`samples`	1–4096	`64`	Cycles' samples

The kinds

Kind	The shot	Its own fields
`turntable`	one turn, eased to dwell front and back and whip through edge-on, so the piece never reads as a flat stick
`clay-metal`	the same turn twice, in clay and in metal, matched frame for frame, for a scene to sweep from one to the other
`macro`	an insert close on one detail, the camera pushing in slowly as the piece drifts under it. Cut in and out hard	`angle`, `focus`, `zoom`, `drift`
`build`	the piece assembles from its named parts, each seating at its second, while it swings about its hero angle	`angle`, `swing`, `parts`

Field	Default	Notes
`angle`	`35`	degrees: 0 is the front, 35 the hero three-quarter
`focus`	`[0, -0.5, 0]`	the detail, in shares of the piece's box from its centre, each −0.5 to 0.5
`zoom`	`0.3`	how much of the piece the frame spans, as a share of its longest side
`drift`	`8`	degrees the piece drifts over the clip
`swing`	`40`	degrees a build swings about its angle over the clip
`parts`	`[]`	`{ name, at }`: an object's name in the model and the second it seats. A build needs at least one; unnamed objects are seated throughout. Use a GLB or OBJ with one object per part

A turntable or a clay-metal is a starting point like any other: change the recipe to fit the piece, and render more than one shot of it.

In a video

The storyboard lists each recipe with the scenes that show it:

{ "shots": [{ "recipe": "shots/pendant.json", "scenes": ["reveal", "close"] }] }

Each shot runs through the job in order, and the scenes showing it wait until it settles. Blender takes the gpu lane, one process at a time:

Key stills. front, hero, side, and back, at 0, 35, 90, and 180 degrees, in renders/shots/<id>/stills/.
Review. A reviewer judges the stills into reviews/shot-<id>-k<try>.json. A revise has the storyboarder change the recipe and renders fresh stills, two tries in all. After the last, the frames render from the last recipe, and the choice is recorded.
Frames. Each pass in chunks estimated under nine minutes each, every chunk a node of its own.
Clips. Each pass as VP9 with alpha, <pass>.webm, and manifest.json.

A shot's nodes are keyed by its recipe and the model's hash, so a changed model renders again.

By hand

rapid shot shots/pendant.json --stills     # the key stills first
rapid shot shots/pendant.json              # the whole shot

See rapid shot for rendering one pass or a range of frames.

In a scene

A shot is a clip like any other. It plays over the field with its transparency, and the runtime seeks it to the frame:

<video src="../renders/shots/pendant/metal.webm" data-el="pendant" data-role="object" data-start="0.4"></video>

Look at stills/ to see the piece, and manifest.json for its size and frames. For a clay-metal shot, stack clay.webm and metal.webm in one box and sweep a mask from one to the other. See video clips.

The shot is the scene's hero: put it in the key frame's assets, and never redraw the product in CSS.

Blender shots

#A recipe

#The kinds

#In a video

#By hand

#In a scene

A recipe

The kinds

In a video

By hand

In a scene