User flagged the current walls as looking off. Investigation: coord (1, 1)
in FG_Fortress.png is actually a tan stone FLOOR tile — no brick texture,
no capstone, no depth — which is why a row of them read as pavement rather
than a wall.
Swap to coord (13, 4): the middle column of a 3-tile-wide capped wall in
the autotile region. Used as a single non-autotile sprite, it shows a dark
medieval brick wall with a visible top cap, brick coursing, and mortar
shadow. The side-by-side simulation at /tmp/wall_rows.png makes the
difference obvious — capped brick reads as a real wall, the floor tile
reads as graph paper.
Phase 5 wall rendering stays non-autotile (every wall uses the same sprite
regardless of neighbours), so even at corners the cabin will read more
clearly as a stone structure. Autotile pass is a separate future task.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>