- settings.volumetric_view (General settings › Display, third switch) replaces
the alpha entry, the header projection toggle and the phone-menu item; one
rule for card, sidebar page and kiosk; editors stay Flat; backend accepts
only a boolean, support package copies it.
- Raised tiles in 2.5D View: no ring, rounded body min(0.275 D, 0.3 h), edge
0.1 D with the lab filters, ×1.12 size also in layout/collision, lift
0.075 D, one floor-shadow layer under all markers (theme × floor table),
frames hugging tile and edge (Alert > Focus > Selected > Hover), forced
colours without edge and shadow (src/iso-tiles.ts, styles/iso-tiles).
- Soft sun wash instead of projected Flat wedges (src/iso-sun.ts): same gates
and windows as sun_rays, length from elevation, parallelogram along the sun,
tone and streaks by floor lightness, sill line.
- Walls take the user's wall colour (top opaque, sides × .77/.68/.60); theme
rules for walls/openings/labels removed; furniture uses the Flat stroke rule.
- Smokes smoke_iso_tiles/iso_sun/iso_theme_walls/volumetric_setting, 16 new
mutants, acceptance scenes STAGE6_ACCEPTANCE_SCENARIOS (golden with their
Linux CI baselines), ACCEPTANCE.md side by side.
Issue: #649
User-Visible: yes
Claude