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https://github.com/jkdansereau/goldeneye-pc-port.git
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James Dansereau
8482ba3ed1
structured fields + x86-64 loop-stride bug; fix designed, handoff updated - Finding D33 in docs/PCPortResearch.md: the .z64 stores multi-byte structured fields in big-endian byte order (bit-packed streams raw); per-field load-time transform rule (u32 bswap32 / u16 bswap16 / u8 identity) validated over all 173 animation entries; full blob layout mapped; exact reproduction of the gdb-observed garbage values. - Second root cause: expand_ani_table_entries iterates s32** (+8 bytes/iter on x86-64 vs +4 on N64), rebasing only even-indexed entries (verified in compiled binary). Fix design: romdataFixupAnimationData() in port/, one call between romCopy and expand, s32* loop stride fix. - docs/HANDOFF.md rewritten with the implementation task; AGENTS.md phase status updated. tools_pc/disasm.py (BE ROM research tool) added.
54 lines
5.8 KiB
Markdown
54 lines
5.8 KiB
Markdown
# AGENTS.md — GoldenEye 007 PC Port
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## What this is
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- `n64decomp/007`: WIP decompilation of GoldenEye 007 (N64), byte-matches US/EU/JP ROMs.
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- Active work: **PC port** modelled on the Perfect Dark PC port (same Rare "Indy" engine family).
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- **Read `docs/PCPortResearch.md` first** — architecture, GE-specific RSP deltas, phased plan, and review findings (A1–D33 in §11; current handoff + plan in §H).
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- **Starting a fresh session?** Read `docs/HANDOFF.md` — the paste-ready brief with the immediate task, standing procedure, and environment gotchas.
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## Non-negotiables
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1. **N64 build untouched.** `Makefile`, `tools/`, `rsp/`, `ld/` belong to the N64 build. Never modify them for the PC port.
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2. **Game logic is unmodified.** The decomp's control flow and behavior are ground truth for 1:1 fidelity — never change them. All N64 *hardware* dependencies are satisfied by the `port/` layer; if a game file seems to need a behavioral change, stop — the fix belongs in `port/`. **Narrow exception (ABI/layout only):** the 32→64-bit transition forces a small class of mechanical, semantics-preserving edits that cannot be isolated in `port/` — chiefly pointer-width reconciliation in ROM-serialized structs (a struct with a 32-bit-pointer field misaligns when read as 64-bit). These follow the PD ground-truth pattern (store the embedded address as `u32`, cast to a real pointer at the use site), change no logic or behavior, and are each documented in `docs/PCPortResearch.md` §F/D3x. No other game-code edits are permitted.
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3. **Region macros mirror the Makefile.** `CMakeLists.txt` `REGION_DEFS` must match the N64 Makefile's per-region macro set exactly (finding A1). Divergence = silent branch divergence + link failures.
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4. **`src/libultrare/Makefile.libultrare` is ground truth** for original-vs-Rare libultra files (finding B3). The PC build compiles: `libultra/audio`, `libultrare/audio` (drvrNew/env/reverb), `libultra/gu`, and `libultrare/io/vitbl.c` only. All other `io/` + `os/` files are excluded and shimmed in `port/src/libultra.c`.
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5. **`rsp/graphics/gmain.s` is the RSP ground truth** — the authoritative reference for which GBI commands GE emits (modified fast3d, 1545 lines). We do not run it on PC; `port/fast3d/` replaces it. Use it to validate the software RSP's command decoding and the custom CC/RM modes.
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## Critical files
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| File | Role |
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|---|---|
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| `docs/PCPortResearch.md` | Research + plan + findings (A1–C2). Read first. |
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| `CMakeLists.txt` | PC build (parallel to the N64 Makefile). Source list + `REGION_DEFS` live here. |
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| `port/src/` | Shims: `libultra.c` (OS API), `gesched.c` (scheduler), `n64stubs.c` (boot/TLB/FPU/rmon), `random.c` (PRNG ported verbatim from `random.s`), `ucode.c` (microcode segment markers), `main.c`, `video.c`, … |
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| `port/fast3d/` | Software RSP (adapted from the PD port). The main Phase 2 work. |
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| `rsp/graphics/gmain.s` | GE's RSP ucode — ground truth for GBI/CC/RM. |
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| `PD_PORT_CHECKOUT` | Perfect Dark PC port checkout — ground truth for the port layer. Its `port/fast3d/` is the starting point for ours. |
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## Build
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```sh
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./build-pc.sh ntsc-final # or pal-final / jpn-final
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```
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Needs CMake + SDL2 + zlib + OpenGL (MSYS2 packages: see `build-pc.sh` header). ROM goes in `./data/` (not distributed).
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## Verification ritual (after any build-affecting change)
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1. **Undefined symbols.** Every symbol referenced by the compiled set (see `CMakeLists.txt`: `SRC_GAME`, `SRC_ENGINE`, `SRC_LIBAUDIO`, `SRC_LIBULTRARE_AUDIO`, `SRC_LIBULTRARE_DATA`, `SRC_GU`, `SRC_PORT*`) must be defined exactly once in the compiled set or in `port/`. Symbols that live in EXCLUDED files (`libultra/io/*`, `libultrare/io/*` except `vitbl.c`, `libultra/os/*`, `libultrare/os/*`, `sched.c`, `rmon.c`, `vi.c`, `src/*.s`) must be provided by `port/src/libultra.c`, `gesched.c`, `n64stubs.c`, `random.c`, or `ucode.c`.
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2. **Duplicates.** No symbol defined twice across the compiled set (watch `sp_*` stacks, `rmon*`, `os*` shims, segment markers).
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3. **Syntax.** Every touched file must parse; once the toolchain is installed, `./build-pc.sh` is the final word.
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Run `/linkcheck` for this sweep. Record new findings in `docs/PCPortResearch.md` §11 style (next label after the last used).
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## Phase status
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- **Phase 0 (scaffolding):** done, committed.
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- **Compile+link milestone:** all ~235 TUs compile and `ge007.x86_64.exe` links clean (`ninja ge007 -k 0`, 236/236). Findings D7–D17 in `docs/PCPortResearch.md` §11; asset stubs in `port/src/assetstubs.c`, fast3d no-ops in `port/src/gfxstub.c` (delete when real fast3d lands).
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- **Phase 1 (boot to window):** done — ROM loads/validates/maps at cart base 0x10000000 (`romdata.c`), SDL2 window + GL clear loop (`video.c`), absolute asset symbols from `scripts/gen_romassets.py` → `port/src/romassets_<r>.s` (findings D18–D23).
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- **Phase 1.5 (boot to first frame):** IN PROGRESS — mainThread runs through `bossInitMainthreadData()`; D31 (langInit file-load SIGSEGV) fixed via real-zlib decompression (`port/src/rzdecomp.c`, replaces the excluded `src/game/decompress.c`+`zlib.c`). Current blocker is **D32** (ROM-struct pointer-width): Part A (u32 layout in `ModelAnimation`) done; Part B **root-caused (D33)** — the ROM stores structured fields big-endian (per-field load-time fixup needed) + an x86-64 loop-stride bug in `expand_ani_table_entries`; fix designed, implementation next. Recurring sub-task: ABI/layout fixes per the D32 procedure (§H) as more asset loading is reached.
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- **Phase 2 (rendering):** bring in PD fast3d (replaces `port/src/gfxstub.c`), verify custom CC/RM modes against `gmain.s`, port the scheduler; replace asset stubs with ROM-backed data (D16). Assumes ABI-clean data loading from Phase 1.5.
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- **Phase 3 (audio + input):** libaudio → SDL; decide the ASP strategy (C2: `aspMain*` dummies in `ucode.c`).
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- **Phase 4 (saves + polish):** file-backed EEPROM; PFS/motor already no-op stubs.
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