Cesarus85--mjolnir-vr/docs/object_matching_logs/point_physics_obj.md

source/physics/point_physics.obj strategy ledger

This retroactive ledger records preserved strict measurements and explicitly marks the detail lost before per-object experiment matrices were required.

Scope and baseline

• Compiler: XDK 3911 CL.Exe 13.00.9254.1, /O2 /Oy- /DDEBUG /Dxbox.
• January target: build/split/source/physics/point_physics.obj.
• Historical baseline: 5/6 functions exact; _point_physics_update was the only residual.
• Current verified inventory: 6/6 functions exact, 1,822/1,822 meaningful code bytes, and 220/220 data bytes. .text, .rdata, .data, and .bss all report 100% after a clean XDK 3911 rebuild.

Parked residual

Function	Size T/B	Relocs T/B	Hash T/B	Measured residual	Class
_point_physics_update	0x570/0x570	68/68 identities	5aca2728fa2d89a716057b07ccbcc1e00cbf126644391dcf1a534707f5cba88c / 93750650472a8e7cfc7dff5fd05b16a5d0b61d4ba611b324a6d1612ed82dbeb4	First divergence is target MOV ECX,EAX versus candidate three-byte MOVZX from CL, shifting later relocations by one; additional commutative x87 operand-order differences remain.	TU-context optimization

Preserved experiment history

Five grounded low-byte/current-flags source shapes were built. The untouched source remained best at ordinary 99.39632%. Attempts to force the byte form introduced extra loads/spills and regressed the function. Individual transient hashes and source diffs were not retained by the historical lane.

Do not repeat generic casts, low-byte snapshots, current-flags aliases, or declaration-order variants without new evidence. Do not use volatile, assembly, byte patches, undefined behavior, or flag changes.

Reopen and disposition

Reopen only with a legal-C use/lifetime shape proven to select the target two-byte move while retaining the 68-relocation graph, or with original local/source provenance. Recheck the 8-byte .bss under strict ownership rules before any object admission.

Upstream resolution (2026-08-07)

The completed object in punpckhdq/halo commit 76a2766930a98f946d669c6db3565c95301d11c4 was rebuilt in a pristine detached worktree before any integration. All six functions passed the hardened comparator, including relocation identity. The upstream .rdata (200 bytes), .data (12 bytes), and .bss (8 bytes) also matched the January object.

The commit was then applied to the current campaign in an isolated integration branch. Conflicts were resolved without discarding unrelated current work:

• the January-proven 0x40-byte point_physics_definition layout replaced the incomplete 0x34-byte HCEX-derived layout;
• the anonymous 8-byte point_physics_globals block was replaced by the two target-owned four-byte globals;
• the collision-user enum was restored so the source names user 13 instead of retaining a magic number;
• a typed point_physics_definition_get() macro and size assertion were added to retain the project house rules.

The consolidated Halo build completed successfully. The final strict function measurements are 6/6 exact, with _point_physics_update at 0x570 bytes and 68/68 relocations. The old MOVZX/x87 residual was therefore a type/source- provenance problem, not a permanent compiler tie.

Disposition: strict object complete; eligible for canonical admission after the whole-tree regression manifest check.

House-rule compliance re-audit (2026-08-07)

The admitted source and header were re-read against docs/house_rules.md and Berthalamew's formatting/access guidance. Parameters and no-argument void lists are vertically formatted, every void definition ends with an explicit return;, tag access goes through the typed point_physics_definition_get() macro, and there are no raw object accesses, alignment coercions, assembly, volatile, __forceinline, or optimization pragmas. Files use CRLF consistently. No compliance edit was required.

Independent atomic salvage revalidation (2026-08-13)

The old completion was treated as untrusted and first transplanted into a fresh worktree at campaign parent e30b15682e8745d5aa8ceb5cb4e455f3bedfcc83. After it passed there, the result was transplanted again onto authoritative code tip 19236aca35b1a319bc4ed050bf628b2f4f9e5bb0 and every code, data, shared-header, build, and tooling gate was repeated. That explicitly includes the newly landed collision_features.obj changes to real_math.h; they caused no point-physics or sibling regression. The current XDK 3911 compiler and the freshly re-split January target were used for every measurement. This audit found two ownership details that the old completion report had missed:

• debug_point_physics is defined by January's source/linker_common.obj, not by point_physics.obj. Keeping the upstream definition here produced a 12-byte rebuilt .bss against the target's 8 bytes. Removing that duplicate definition leaves an ordinary external reference and restores the exact target-owned 8-byte block.
• The two anonymous BSS fields have distinct meanings and offsets. January stores the water mass factor at offset 0 and the air mass factor at offset 4. With the declarations in the old order, VC7 emitted the two statics in the reverse layout. Declaring water before air produces the proven target layout: _global_water_mass_over_radius_cubed at 0 and _global_air_mass_over_radius_cubed at 4.

The relevant symbols.json entries now name the private renderer and both BSS fields. Re-splitting the target with those aliases makes the hardened section_infos_equal proof direct; no fuzzy or byte-only exception is used.

Strict function evidence

Function	Padded bytes	Relocations	Normalized SHA-256	Result
_point_physics_initialize_for_new_map	0x30	6	9010f31148fb9f42a69e7b6dc423092e9c8d4f6e639697c11ef26ad900c91cd4	exact
_point_physics_dispose_from_old_map	0x10	0	499f1f307c1cb989f968a6b7fcaec591e1828877223d0b0e7e8e8b76cde8c9ca	exact
_point_physics_definition_get_mass	0x20	0	8792859ba0282c4bb0a61e5c5a43f9a5bbde5b578125c991b2a2a2b8dcae99ee	exact
_point_physics_definition_interpolate	0x160	19	06fcdedf097eb65d7a48b29d30bdf0364aebfd23a79f8aa3bf6abc67e19571a3	exact
_render_debug_point_physics	0x30	3	f8dfcdb85893a7f5ff751bcfc788d259cd7f1d13ddfa752c6312c547932eccaa	exact
_point_physics_update	0x570	68	5aca2728fa2d89a716057b07ccbcc1e00cbf126644391dcf1a534707f5cba88c	exact

All six functions pass strict size, normalized-byte, relocation-address, relocation-type, destination, and addend comparison. This is 1,888/1,888 padded code bytes and the ordinary report's 1,822/1,822 meaningful code bytes.

Owned data and ownership evidence

All 17 target-owned COFF sections pass section_infos_equal: the six function sections above, nine .rdata COMDATs (182 raw bytes, reported as 200 bytes with target alignment), the 12-byte _global_point_physics_reference .data, and the 8-byte mass-factor .bss.

Owned data	Bytes	Relocations	Normalized SHA-256	Result
nine .rdata COMDATs	200 reported	0	each owner checked independently	exact
_global_point_physics_reference	12	0	ca5622977c575e2fcacb390addd8f0dc1cd2b513916cf76e16b192067b183b53	exact
mass-factor .bss	8	0	af5570f5a1810b7af78caf4bc70a660f0df51e42baf91d4de5b2328de0e83dfc	exact

The split target necessarily labels extracted private sections as external, while VC7 emits the private helper and mass fields with static storage. The aliases, section bytes, exact field offsets, and every relocation destination are unambiguous; the external/static class difference is the known csplit ownership representation, not a different linked address.

Rejected and accepted source shapes

Shape	Measurement	Disposition
Historical incomplete reconstruction	_point_physics_update 0x570, 68 relocs, hash 93750650...; 99.39632%	rejected
Upstream completion copied literally	code exact, but rebuilt .bss 12/8 because it also defined debug_point_physics	rejected
External debug_point_physics; old air-then-water declaration order	.bss size corrected to 8, but symbols measured air@0/water@4 against January water@0/air@4	rejected
External debug flag; water declared before air	.bss 8/8, water@0, air@4; all 17 owners strict	accepted

The five earlier low-byte/current-flags experiments remain recorded above and were not repeated. The decisive improvement came from recovered structure and ownership provenance, not from coercing the compiler.

Blast radius and style audit

The five changed shared headers were followed transitively through the source include graph. Thirty-three translation units were rebuilt in both the clean parent baseline and the candidate. All 1,633 previously strict target-owned sections remained strict; there were zero regressions. External-symbol metadata changed only in physics.obj (the January-owned physics globals are now declared/defined) and point_physics.obj (the intended completion).

The final source follows the house and Berthalamew rules: one parameter per line, vertically formatted (void), explicit final return; in void definitions, a single return where feasible, typed tag_get access through point_physics_definition_get(), named collision-user and result enums, and no raw object access. It contains no assembly, volatile, __forceinline, alignment coercion, optimization pragma, undefined behavior, or byte patch. No original January gameplay bug was identified in this object, so no fake bug comment was added; the duplicate debug-global definition was a reconstruction ownership bug and was corrected outright.

Final gates

• ninja halobetacache_build: passed from a clean full rebuild at the current campaign code state.
• ninja progress: passed; the semantic audit reported zero unit errors, and point_physics.obj reports 6/6 functions, 1,822/1,822 meaningful code bytes, and 220/220 data bytes.
• tools.regression_gate snapshot/check --unit source/physics/point_physics: passed with six still_exact, no failures, no warnings, and no changed nonexact function.
• python -m unittest discover -s tools -p 'test_*.py' -v: 173/173 passed.