Build a 3D scene

Write a scene file, check that no body goes through a prop, and draw a still from its camera on your computer.

A 3D scene is one file that holds people, props, cameras and a timeline. Your agent writes it, and MiniCut checks it and draws it on your computer. Distances are in metres, the floor is at 0 and turns are in degrees.

Before you start, sign in and make a project. See Quickstart. Every command here needs a signed-in computer. Run them in the project folder, ~/.minicut/projects/rain-shop here.

Write the scene

1. Make the folder episodes/ep01/scenes in the project if it is not there. A scene for shot 1 is named c01, for shot 2 c02, and on.
2. Write an operations file in that folder, c01.scene.ops.json. It is data: a list of scene operations with their arguments, and no code.

{
  "ops": [
    { "op": "setWorld", "args": [{ "aspect": "9:16" }] },
    { "op": "addCharacter", "args": [{ "name": "Lin", "body": "female", "position": [-0.8, 0, 0] }], "as": "lin" },
    { "op": "addCharacter", "args": [{ "name": "Chen", "body": "male", "position": [0.8, 0, 0], "facing": "$lin" }] },
    { "op": "addProp", "args": [{ "name": "Table", "shape": "table", "position": [0, 0, 0.9] }] },
    { "op": "addCamera", "args": ["front_medium", { "name": "Front" }], "as": "cam" },
    { "op": "setCamera", "args": ["$cam", { "position": [0, 1.6, 6], "lookAt": [0, 1.4, 0], "fov": 40 }] },
    { "op": "setDuration", "args": [4] }
  ]
}

as names the id that an operation makes, and $lin uses it in a later operation. An operation name that does not exist makes build print the names it takes.

3. Optional: if your agent writes code, run minicut scene api. It prints one import line for a Node.js script. The script ends with await api.save("episodes/ep01/scenes/c01.scene.json"), which checks the scene and writes it. MiniCut never runs the script. Your agent runs it with node.

Build the scene file

1. Build the file:

minicut scene build episodes/ep01/scenes/c01.scene.ops.json

It prints Wrote with the path of c01.scene.json, the count of objects and cameras, the length, and each camera's id and name.

2. Read the camera id in the output. Every build makes new ids, so a camera id from an earlier build no longer fits.

build checks the scene before it writes. If a check fails, it prints each problem, says Not written, and leaves the old file as it was. A file that holds code is refused.

Check the scene

1. Check that no body goes through a prop or the floor:

minicut scene check episodes/ep01/scenes/c01.scene.json

OK ~/.minicut/projects/rain-shop/episodes/ep01/scenes/c01.scene.json: 3 object(s), 1 camera(s), 4 s. Cameras: cam_a6tl (Front). No body goes through a prop or the floor.

2. If it prints problems, change the operations file and build again. Each line names the body part, the prop, how deep and at which second, and how far to move. For example, Lin's left thigh goes 9 cm into "Table" (p_kg3w), at 0 s.
3. To go back to the file before the last build, run minicut scene undo episodes/ep01/scenes/c01.scene.json. The last 20 versions are kept.

Draw a still

1. Draw the middle second of the scene:

minicut scene render episodes/ep01/scenes/c01.scene.json --still middle

The command prints Drawing with the camera and the second, then Rendered with the size in bytes, then the path. With no --camera, it uses the scene's own camera.

2. Open the picture. Without --project or --id, it is in the cache/stills folder of your MiniCut home folder, and the command prints its path. A copy in the labeled folder beside it has a name tag on every asset, for people to read.
3. Optional: to keep the still in your library as a location, add --project rain-shop.
4. Optional: for a smaller picture, add --draft for half of each side, or --size WIDTH with an even width.
5. Optional: to draw the middle second of every shot scene in an episode, run:

minicut scene render --project rain-shop --episode ep01 --still middle

It draws each cNN.scene.json in turn. The last line says how many it drew and how many it did not draw.

Check it worked

The still is a .png that shows the scene from the camera. A scene that fails minicut scene check is not drawn. The command prints Not rendered and the problems. To draw a clip instead of a still, see minicut scene render.

If a step fails

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