feat: Blender-authored roadside districts that rise per chapter

assets/blender/districts/export-districts.py

@@ -0,0 +1,67 @@
+"""Export the district kit to the runtime GLB (positions + indices only).
+
+  blender -b assets/blender/districts/nightdrive-districts.blend --python assets/blender/districts/export-districts.py [-- --preview out.png]
+
+Normals are derived per fragment at runtime (flat shading from screen-space
+derivatives), so the GLB carries no normals, UVs or materials and shared box
+corners stay welded. Writes provenance next to this script.
+"""
+import bpy, json, hashlib, sys, math
+from pathlib import Path
+
+here = Path(__file__).resolve().parent
+root = here.parents[2]
+scene = bpy.data.scenes['Roadside Districts']
+output = root / 'src/assets/nightdrive-districts.glb'
+
+for obj in scene.objects:
+    obj.select_set(True)
+bpy.ops.export_scene.gltf(
+    filepath=str(output), export_format='GLB', use_selection=True, use_active_scene=True,
+    export_apply=True, export_normals=False, export_texcoords=False, export_materials='NONE',
+    export_animations=False, export_cameras=False, export_lights=False, export_yup=True,
+)
+triangles = 0
+for obj in scene.objects:
+    obj.data.calc_loop_triangles()
+    triangles += len(obj.data.loop_triangles)
+provenance = {
+    'asset': 'Nightdrive roadside districts',
+    'source': 'nightdrive-districts.blend',
+    'authorship': 'Original procedural modelling in Blender for this portfolio (author-districts.py); no external assets.',
+    'editable_scene': 'Roadside Districts',
+    'pieces': sorted({o.name.rsplit('_', 1)[0] for o in scene.objects}),
+    'triangles': triangles,
+    'attributes': 'POSITION + indices; flat normals derived at runtime',
+    'export': '../../../src/assets/nightdrive-districts.glb',
+    'sha256': hashlib.sha256(output.read_bytes()).hexdigest(),
+}
+(here / 'nightdrive-districts.asset.json').write_text(json.dumps(provenance, indent=2) + '\n')
+print(json.dumps(provenance))
+
+if '--preview' in sys.argv:
+    target = sys.argv[sys.argv.index('--preview') + 1]
+    names = provenance['pieces']
+    for i, name in enumerate(names):
+        for suffix in ('body', 'light'):
+            obj = scene.objects[f'{name}_{suffix}']
+            obj.location = ((i % 4) * 34 - 50, (i // 4) * 40, 0)
+            mat = bpy.data.materials.new(f'preview-{suffix}')
+            mat.diffuse_color = (0.05, 0.05, 0.08, 1) if suffix == 'body' else (0.1, 0.9, 1.0, 1)
+            obj.data.materials.append(mat)
+    cam = bpy.data.objects.new('preview-cam', bpy.data.cameras.new('preview-cam'))
+    scene.collection.objects.link(cam)
+    cam.location = (95, -95, 70)
+    cam.rotation_euler = (math.radians(58), 0, math.radians(45))
+    cam.data.lens = 30
+    scene.camera = cam
+    try:
+        scene.render.engine = 'BLENDER_WORKBENCH'
+    except TypeError as e:
+        print(e)
+    scene.display.shading.color_type = 'MATERIAL'
+    scene.display.shading.light = 'STUDIO'
+    scene.display.shading.show_cavity = True
+    scene.render.resolution_x, scene.render.resolution_y = 1600, 1000
+    scene.render.filepath = target
+    bpy.ops.render.render(write_still=True)