Remove building export pipeline

README.md

@@ -13,10 +13,8 @@ This repository converts DGM1 elevation tiles into Unity-ready 16-bit PNG height
 - `export_unity/height_png16/` — final 16-bit PNG heightmaps for Unity import.
 - `export_unity/tile_index.csv` — manifest mapping tile IDs to world bounds and global min/max used for scaling.
 - `export_unity/ortho_jpg/` — cropped orthophoto tiles aligned to the terrain grid (JPEG + worldfiles).
-- `export_unity/buildings_obj/` — per-tile clipped CityGML exports as OBJ meshes.
 - `export_heightmaps.py` — main export script.
 - `export_ortho_tiles.py` — exports orthophoto tiles from DOP JP2 inputs using the terrain manifest.
-- `export_buildings.py` — clips CityGML LoD2 tiles per terrain tile and writes OBJ meshes.
 - `AGENTS.md` — contributor guide.
 
 ### Quick Start
@@ -47,10 +45,5 @@ This repository converts DGM1 elevation tiles into Unity-ready 16-bit PNG height
    ```
    This builds `work/dop.vrt` if missing and writes `export_unity/ortho_jpg/<tile>.jpg` + `.jgw` aligned to `tile_index.csv`.
 
-### Buildings (CityGML LoD2 → OBJ)
-1. Ensure LoD2 GML tiles live in `raw_3dgeb_lod2/` (unzipped from `3dgeblod2` bundle).
-2. From `GeoData/`, run:
-   ```bash
-   python3 export_buildings.py
-   ```
-   This clips each GML to the terrain tile footprint and exports `export_unity/buildings_obj/<tile>.obj` (EPSG:25832 coordinates).
+### Buildings
+The building export pipeline is temporarily disabled while we choose a mesh conversion approach (GDAL lacks a native OBJ writer). CityGML LoD2 sources remain in `raw_3dgeb_lod2/`; consider CityGML→glTF/OBJ tools (e.g., citygml-tools + cityjson2gltf) for future integration.

export_buildings.py

@@ -1,102 +0,0 @@
-#!/usr/bin/env python3
-"""Clip CityGML LoD2 buildings per terrain tile and export as OBJ meshes.
-
-Inputs
-- raw_3dgeb_lod2/LoD2_<utm>_<easting>_<northing>.gml : source building tiles
-- export_unity/tile_index.csv : manifest produced by export_heightmaps.py
-
-Outputs
-- export_unity/buildings_obj/<tile_id>.obj : clipped building geometries per tile
-"""
-from __future__ import annotations
-
-import csv
-import os
-from pathlib import Path
-
-from osgeo import gdal
-
-RAW_GML_DIR = Path("raw_3dgeb_lod2")
-TILE_INDEX = Path("export_unity/tile_index.csv")
-OUT_DIR = Path("export_unity/buildings_obj")
-
-OUTPUT_FORMAT = "OBJ"  # glTF driver is not always available; OBJ is widely supported.
-
-gdal.UseExceptions()
-OUT_DIR.mkdir(parents=True, exist_ok=True)
-
-
-def gml_path_for_tile(tile_id: str) -> Path:
-    """Map a DGM tile id (dgm1_utm_easting_northing) to the corresponding CityGML file."""
-    parts = tile_id.split("_")
-    if len(parts) != 4 or parts[0] != "dgm1":
-        raise ValueError(f"Unexpected tile_id format: {tile_id}")
-    utm_zone, easting, northing = parts[1:]
-    return RAW_GML_DIR / f"LoD2_{utm_zone}_{easting}_{northing}.gml"
-
-
-def open_dataset(path: str, purpose: str):
-    """Open a dataset and fail fast with context."""
-    try:
-        ds = gdal.OpenEx(path)
-    except RuntimeError as exc:
-        raise SystemExit(f"{purpose}: {exc}") from exc
-    if ds is None:
-        raise SystemExit(f"{purpose}: GDAL returned None for {path}")
-    return ds
-
-
-def main() -> None:
-    if not TILE_INDEX.exists():
-        raise SystemExit(f"Tile index missing: {TILE_INDEX}. Run export_heightmaps.py first.")
-
-    written = 0
-    skipped = 0
-
-    with TILE_INDEX.open(newline="", encoding="utf-8") as f:
-        reader = csv.DictReader(f)
-        for row in reader:
-            try:
-                tile_id = row["tile_id"]
-                xmin = float(row["xmin"])
-                ymin = float(row["ymin"])
-                xmax = float(row["xmax"])
-                ymax = float(row["ymax"])
-            except (KeyError, ValueError) as exc:
-                print(f"Skipping malformed row {row}: {exc}")
-                skipped += 1
-                continue
-
-            gml_path = gml_path_for_tile(tile_id)
-            if not gml_path.exists():
-                print(f"Missing CityGML for {tile_id}: {gml_path}")
-                skipped += 1
-                continue
-
-            out_path = OUT_DIR / f"{tile_id}.obj"
-
-            src_ds = open_dataset(str(gml_path), f"Could not open {gml_path}")
-
-            opts = gdal.VectorTranslateOptions(
-                format=OUTPUT_FORMAT,
-                spatFilter=(xmin, ymin, xmax, ymax),
-                layerName="Building",  # matches GML layer name
-            )
-
-            try:
-                gdal.VectorTranslate(destNameOrDestDS=str(out_path), srcDS=src_ds, options=opts)
-            except RuntimeError as exc:
-                print(f"VectorTranslate failed for {tile_id}: {exc}")
-                skipped += 1
-                continue
-
-            written += 1
-            print(f"Wrote {out_path}")
-
-    print(f"Summary: wrote {written} building tiles; skipped {skipped}.")
-    if skipped:
-        raise SystemExit(1)
-
-
-if __name__ == "__main__":
-    main()