- Fetch Carto Voyager no-label base tiles and label-only tiles separately,
cached under cache/osm_tiles/{z}/ and cache/osm_tiles/labels/{z}/
- Rasterize both into the orthographic projection via exact inverse projection
(new unproject/pixel_to_geo methods on OrthoProjection)
- Render pipeline: basemap → cloud blend → label overlay (labels above clouds)
- Bilinear interpolation for base tiles; premultiplied-alpha bilinear for label
tiles to prevent dark-fringe artifacts at text edges
- Dynamic zoom selection (floor-based) from actual geographic bounding box
- Fix horizontal squish: derive HALF_W_DEG from pixel aspect ratio so
degrees-per-pixel is equal on both axes
- Add --no-basemap flag to skip tile fetching for offline/fast use
- Remove hardcoded city markers/labels when tile label overlay is present
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
