scripts/README.md

# Pipeline scripts

These scripts reconstruct City3D-MultiGen from the source data, organized by city.
Only the canonical (non-duplicate) version of each stage is kept.

## `melbourne/`
Processing for the City of Melbourne 3D Point Cloud.

| Script | Role |
|--------|------|
| `export_las_blocks_noKML.py` | The full tiler: partitions the source LAS into 150 m tiles and produces the per-tile point cloud, **DSM**, and BEV render. |
| `grid_from_kml.py` | Builds the tile grid (`metadata/*_grids.json`) from the KML tile index. |
| `Obtain_corresponding_map_signed.py` | Fetches satellite + styled map from the Google Maps Static API and parses the per-class semantic masks. **Reads `GOOGLE_MAPS_API_KEY` and `GOOGLE_MAPS_URL_SIGNING_SECRET` from environment variables.** |

## `holicity/`
Processing for HoliCity (London) FBX meshes.

| Script | Role |
|--------|------|
| `export_las_blocks_noKML.py` | Samples point clouds from the meshes and tiles them (same full tiler as Melbourne). |
| `convert_coord.py` | Converts HoliCity local coordinates to geographic coordinates. |
| `add_coord_head.py` | Writes the geographic coordinate header onto each tile. |
| `check_coord.py` | Sanity-checks the coordinate alignment of generated tiles (optional utility). |
| `Obtain_corresponding_map_signed.py` | Fetches satellite + semantic maps (same Google API, your own key). |

## `build_dataset.py`
Top-level orchestrator: tiling → map fetching → DSM/BEV, assembling the per-tile
layout described in the top-level README.

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### ⚠️ Before running
- Set your Google credentials as environment variables (see top-level README).
- API keys/secrets have been removed from these scripts and are read from the
  environment. **Do not re-introduce hardcoded credentials** — this repo is public.
- Edit the input/output paths at the top of each script to match your local layout.