# Twelve-scenario examples

One source instance from each of the twelve scenario families is included. Seven examples have a paired, officially retained appearance-transfer video; the remaining five contain raw data only. No experimental gas transfers are included. These are illustrative examples, not the official benchmark split.

| Material | Scenario | Sample ID | Transfer |
| --- | --- | --- | --- |
| rigid | rigid-falling_objects | `falling_objects_0098` | Included |
| rigid | rigid-rolling_objects | `rolling_objects_0037` | Included |
| rigid | rigid-dominoes | `dominoes_0000` | Included |
| soft | soft-falling_objects_on_soft_pad | `falling_objects_on_soft_pad_0029` | Included |
| soft | soft-gravity_draping_flag | `gravity_draping_flag_0033` | Included |
| soft | soft-gravity_tightening_soft_rope | `gravity_tightening_soft_rope_0041` | Included |
| liquid | fluid-rigid_objects_in_water_tank | `rigid_objects_in_water_tank_0012` | Not available |
| liquid | fluid-draining_tank | `draining_tank_0010` | Included |
| liquid | fluid-u_connector | `u_connector_0012` | Not available |
| gas | gas-gas_smoke_stack | `gas_smoke_stack_0012` | Not available |
| gas | gas-impact_smoke_dispersion | `impact_smoke_dispersion_0012` | Not available |
| gas | gas-gas_flame_heating | `gas_flame_heating_0012` | Not available |

Raw data is stored under `raw/MATERIAL/SCENARIO/SOURCE_ID/`, including `render.mp4`, scene JSON files, `frames/`, and `render_assets/`. Retained variants are stored separately under `transfer/MATERIAL/SCENARIO/SOURCE_ID/VARIANT.mp4`. Videos and annotations are unchanged; Raw and transfer are associated by sample ID and manifest paths.

Solid/liquid examples contain RGB, ID-mask, depth, and normal frames as supplied by their source. Gas examples contain RGB and per-object opacity channels under `frames/mask/<object_id>/frame_XXXX.png`; consult `render_assets/pass_metadata.json` for encoding and object identities. These are not ordinary binary masks. Data presence does not certify compatibility with every evaluator mode; full rigid scoring still requires the evaluator's complete reference contract and reviewed actor semantics.

`manifest.json` records relative reference/transfer paths, the original transfer filename, frame-file counts, and video SHA-256 hashes. A paired transfer is an appearance variant of the same source instance, not a model prediction or a replacement for raw simulation annotations.

The [generation example manifest](../manifests/generation.examples.json) covers all twelve cases, using transfer frame 0 where available and raw frame 0 otherwise. Its prompts and seed 42 are demonstrations, not the official paper configuration. See [Usage](../README.md#usage) and the [generation protocol](../docs/generation.md).

Source scene files may retain environment-specific asset paths. Adapt those before rerendering. Source masks and meshes remain unchanged and should be interpreted with their accompanying metadata.

## Local directory layout

The current local example root is `data/`. A separate `example_data/` download uses the same internal layout.

```text
data/                         # downloads use example_data/ with identical internals
├── manifest.json
├── raw/
│   ├── rigid/dominoes/dominoes_0000/
│   │   ├── render.mp4
│   │   ├── frames/
│   │   └── render_assets/
│   ├── soft/
│   ├── liquid/
│   └── gas/smoke_stack/gas_smoke_stack_0012/
│       └── metadata.json
└── transfer/
    ├── rigid/dominoes/dominoes_0000/appearance_00.mp4
    ├── soft/gravity_draping_flag/gravity_draping_flag_0033/black_disc.mp4
    └── liquid/draining_tank/draining_tank_0010/appearance_02.mp4
```

Directory names for gas are `smoke_stack`, `impact_smoke_dispersion`, and `flame_heating`; original source IDs retain their `gas_` prefixes where present. CLI identifiers remain `gas_smoke_stack`, `impact_smoke_dispersion`, and `gas_flame_heating`, as recorded in the manifest. Raw-only cases have no matching sample directory under `transfer/`. All manifest paths are relative to this root.

## Gas evaluation metadata

The three gas examples now include `raw/<material>/<scenario>/<sample_id>/metadata.json`, adapted from their existing `runtime_scene.json`, `render_assets/mask_ids.json`, and `render_assets/pass_metadata.json`. The metadata declares exactly one evaluated smoke object, its opacity directory, and explicit actor occluder channels. Source files and image pixels are unchanged. `scripts/prepare_gas_metadata.py` can recreate or validate this index; differing existing metadata is not overwritten. These indexes enable reference loading, not a guarantee of a valid model score.

## Canonical metadata for all examples

All twelve Raw sample directories now contain `metadata.json` at `raw/<material>/<scenario>/<sample_id>/metadata.json`. Rigid, soft and liquid metadata is exported from worldModelMetric's built-in Blender-manifest adapters, retaining their normalized fields and original manifest provenance. Gas metadata uses the reviewed gas adapter described above. The dataset manifest records each metadata path and SHA-256. RGB coverage and the first frame of each evaluated mask/opacity channel were checked with the upstream loaders; this is input validation, not a completed model evaluation.