Mirror the existing ACDREAM_DUMP_CELLS pattern for GfxObj-owned geometry:
when ACDREAM_DUMP_GFXOBJS lists a hex GfxObj id, the first
PhysicsDataCache.CacheGfxObj for that id writes the full resolved
polygon table to a JSON fixture under
tests/AcDream.Core.Tests/Fixtures/issue98/0x{id:X8}.gfxobj.json (override
dir via ACDREAM_DUMP_GFXOBJS_DIR).
Motivation: the existing [resolve-bldg] probe captures GfxObj-level
metadata (id, BSP root radius, entity origin) but emits
"hitPoly: n/a (BSP path — side-channel not written)" because the
BSPQuery wire site that would populate LastBspHitPoly never landed.
A polygon-level dump at cache time bypasses that gap — one capture run
yields the FULL polygon table, fixture-loadable by the harness's
RegisterCottageGfxObj helper (next commit).
See docs/research/2026-05-23-a6-p3-issue98-comparison-harness-findings.md
for the cottage GfxObj 0x01000A2B context: landblock-baked static at
entity origin (130.5, 11.5, 94.0), responsible for the head-sphere cap
from below at world Z=94.0 that issue #98 is documenting.
Test baseline: 1183 + 8 pre-existing failures (serial run; +5 new tests
all pass; was 1178 + 8 pre-session).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>