ShadowObjectRegistry computes the CELLARRAY once per registration under
Contract A (cylsphere route from the Setup's collision cylspheres, else the
bbox route over the whole visual part array) and derives BOTH products from
it: the collision rows (_entityToCells/_cells, CShadowObj per cell via
add_shadows_to_cells @0x00514ae0) and the per-part render entries
(AddPartsShadow @0x00517e40). The second, independent collision flood is
gone. A caller that supplies no part array floods from its collision shapes
exactly as before, so every legacy expectation holds byte-for-byte.
The staged SetPosition pipeline now carries the retail part array, cell
array, route, and entries through TryCaptureOwnerState/InstallOwnerState
and publishes them beside the collision cell replacements, honoring the
keep-when-empty rule (SetPositionInternal num_cells gate, pc:283540) for
both products together; two new tests pin a cross-cell move and the
keep-when-empty case. Behavior change, retail-exact: an object with
decorative non-BSP parts now has its collision shapes registered in every
cell those parts reach (pinned by a two-cell fixture); all-BSP objects are
unchanged. Movement paths still take collision cells from the transition
and recompute the retail product separately; chunk 4 unifies them on the
transition's array as retail does. No particle emitter reaches this registry.
Gates (implementer's isolated worktree at identical content): Release
build 0/0; Core 4,961/4,961; App hermetic 6,760/6,760; collision/InstalledDat
fixtures 63/63; Runtime 1,884/1,884; Content 213/213.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>