A 14 m concrete wall now encloses the city 24 m beyond its outermost
blocks. It is in the collision index (not the pick index), blocked on
the navigation grid so residents and routes stay inside, and walk/fly
positions are clamped within it so nobody leaves by flying over.
Posters are pasted on the city side at random spots, sizes and tilts
(up to 25 degrees), one per ~35 m, overlapping like a real hoarding.
They are painted into one atlas from civic slogans plus facts about the
loaded codebase (welcome, tallest tower, largest district, most
connected file), seeded by the repository name so each city's wall is
stable. The wall shader draws concrete courses and joints with a lit
coping, and the minimap outlines the wall. README covers routes,
residents, the wall and security alerts.
Little glowing green stick figures, in the spirit of Darwinia, stroll
the streets: each walks toward a random reachable point in plain sight
on the navigation grid, pauses, and about a third of the time heads
toward a nearby resident instead, so they gather in small crowds. They
are camera-facing sprites drawn procedurally in the fragment shader
with a walk cycle, flicker and halo, grown with altitude so crowds stay
visible from the helicopter, and fogged like everything else.
About one resident per 2,500 m² of city (40 to 600), spawned only on
the city's own streets. Because they keep the city animating, Settings
has a City residents switch (saved with the other preferences). The
simulation is seedable and tested to keep everyone on walkable ground.
City mode builds a 3 m occupancy grid (buildings grown by half a metre
blocked, pavements slightly dearer than roads). Selecting a file runs
one Dijkstra from its building's street doors that stops once every
imported file's doors are settled, then straightens each route to its
necessary turns. Buildings boxed in by neighbours route to the nearest
reachable street. Routes are drawn as glowing ground ribbons with
chevrons flowing toward each dependency (cyan known, amber inferred)
and on the minimap; walking from the helicopter starts at the first
route's door facing along it.
Distances are float64: float32 rounding made equal-cost paths look
like improvements and flooded the queue (a hang on real cities). Tests
cover detours, enclosed targets and a large-city time budget; real
prometheus data routes 24 imports in about 60 ms.