Found while investigating #189 (missing fountain/candle particles):
reverting the A7.L1 light-carrier hydration fix (9ebb2060) made the
Town Network fountain's water-spray particle work again, which didn't
fit the earlier dat-truth finding that the fountain's own entity was
never touched by that fix. Traced with ACDREAM_DUMP_ENTITY: the
fountain's hydrated entity.Id shifted between reverted (0x400007F8)
and fixed (0x40000815) builds — a 29-id delta matching the extra
mesh-less light carriers the A7.L1 fix now keeps alive earlier in the
same landblock's hydration pass.
Root cause: GameWindow's interior-entity id scheme
(interiorIdBase + localCounter, "0x40XXYY##") reserves only 8 bits
(256 values) for a landblock's ENTIRE interior static population — a
residual explicitly flagged in the #119 fix's own comment ("counter
overflow past 0xFF still bleeds into the lbY byte"). The Town Network
hub (205 cells, one landblock) already sat at 248 before A7.L1; the
light fix pushed it to 277, past the boundary. 0x40000815 decodes as
landblock Y=0x08 — NOT this dungeon's true Y=0x07 — the exact #119
cross-landblock aliasing bug, reincarnated by entity count instead of
a computation bug. EntityScriptActivator keys particle-script
instances by entity.Id directly (no landblock-hint disambiguation
unlike the #119 batch cache), so the aliased id silently broke the
fountain's script tracking.
Fix: AcDream.Core.World.InteriorEntityIdAllocator widens the counter
8->12 bits (256->4096) by shrinking the fixed class prefix from a
full byte (0x40) to its top nibble (0x4_) — verified safe against
every entity.Id classification check in GameWindow (none decode X/Y
back out, they only check thresholds/prefixes). Added a loud
one-time [id-overflow] log if a landblock ever exceeds the new
budget, so this class of bug can never hide silently again.
Core 2675+2skip / App 741+2skip / UI 425 / Net 385 green.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
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