- street_mesh.py: continental zebra markings (0.5 m bars, 0.5 m gaps, 3 m
band) at all three signalised crossings, triangles not quads (FBX SDK
refuses to triangulate the crown-twisted quads), stripes +6 cm above the
DEM so they stay above the road surface; winding flipped so every street
surface faces up (road/sidewalks/markings were 100% down-facing and
invisible in engine once the terrain stopped covering them).
- terrain_from_dem.py: cut a 10.7 m corridor around the Hollywood Blvd
centreline so road, kerbs and sidewalks are not buried under the terrain;
sidewalks themselves cover the transition band, walk-check stays at 0 holes.
- Blender builders save with a writability guard + fatal failure: *.blend
is LFS-lockable and checks out read-only; a failed save previously left
downstream steps building from stale files.
- ue_import_site.py: Crossing_Markings imports with no collision (paint on
the road); ue_build_demo_map.py stages it and chmods the lockable .umap
before saving (save_map silently returned False on read-only maps).
- ue_build_review_map.py: demo-crossing camera moved to the real crossing
(s=130.1 m -> UE -24291,-1340) and fixed the ensure_writable path (was
missing the .umap suffix, so the chmod never fired).
site-2026-11-06.blend gathers terrain, street and blockout into categorised
collections: 281 objects, ~58k triangles. A downward raycast on a 1 m grid along
both sidewalks and the designated crossing finds no holes, so nothing drops the
player on either side. Two steps are flagged: 15.8 cm at the sidewalk's outer
terrain seam and 10-13 cm ramps at the crossing flush transitions, steeper than
a real 8% ramp.
Sampling is projected through PROJ: placing points with the OSM spherical
approximation put them metres off the UTM meshes and reported 91 phantom holes.
zwitschi