# Phase-by-Phase Audit: Decompiled vs Guessed

Every AC-specific algorithm should be ported from the decompiled client
or verified against ACME's ClientReference.cs. This audit flags which
parts of each shipped phase are properly sourced vs which were guessed
and may need re-verification.

Legend:
- ✅ VERIFIED — ported from decompiled code or verified against ACME/ClientReference
- ⚠️ REFERENCE — ported from ACE/ACViewer/holtburger (good but not decompiled ground truth)
- ❌ GUESSED — written without checking any reference, or reference was inadequate

---

## Phase 1 — Terrain + Plugin Scaffold

| Component | Status | Source | Notes |
|-----------|--------|--------|-------|
| LandblockMesh height indexing (x-major) | ✅ | ACME ClientReference.cs | Fixed after initial y-major bug |
| LandblockMesh triangle split direction | ✅ | ACME ClientReference.cs + AC2D | Confirmed via 25,600-cell conformance sweep |
| LandblockMesh vertex positions | ✅ | ACME ClientReference.GetVertexPosition | Matches decompiled ConstructVertices |
| Height table lookup | ✅ | ACME ClientReference.GetVertexHeight | Direct table[byte] |
| Plugin host (ALC, lifecycle) | N/A | acdream-specific design | Not AC-specific |

## Phase 2a-2d — Static Meshes + Scenery

| Component | Status | Source | Notes |
|-----------|--------|--------|-------|
| GfxObjMesh.Build (vertex/UV/normal extraction) | ⚠️ | WorldBuilder ObjectMeshManager | Cross-checked against ACME. Winding order opposite from ACME (latent) |
| GfxObjMesh neg-side polygon emission | ⚠️ | WorldBuilder ObjectMeshManager | acdream is MORE correct than ACME here |
| SetupMesh.Flatten (multi-part assembly) | ⚠️ | WorldBuilder + ACViewer | Third-fallback frame added from ACME |
| SceneryGenerator LCG algorithm | ✅ | Decompiled chunk_00530000.c:1144 + chunk_005A0000.c:4858 | All 5 algorithms verified, annotated with decompiled refs |
| SceneryGenerator road exclusion | ✅ | ACViewer + ACME | Post-displacement check added |
| SceneryGenerator building exclusion | ✅ | ACME GameScene | Ported |
| SceneryGenerator slope filter | ✅ | ACME TerrainGeometryGenerator | Ported |
| EnvCell static objects (interior) | ⚠️ | ACViewer EnvCell.cs | Frames are landblock-local (learned empirically) |

**ACTION NEEDED:** SceneryGenerator LCG constants should be verified against decompiled code.

## Phase 3a-3c — Lighting + Terrain Blending

| Component | Status | Source | Notes |
|-----------|--------|--------|-------|
| Directional lighting (Lambert + ambient) | ❌ | Guessed | Sun direction/ambient constants are made up. Should check decompiled AdjustPlanes (FUN_00532440) |
| Per-vertex terrain normals | ⚠️ | Central differences on heightmap | Not from decompiled code. ACME's AdjustPlanes accumulates face normals |
| Terrain texture blending (TexMerge) | ⚠️ | WorldBuilder LandSurfaceManager | Comprehensive but not verified against decompiled |
| GetPalCode | ✅ | ACME ClientReference.GetPalCode | Exhaustive conformance test (1M combos) |
| Alpha atlas loading | ⚠️ | WorldBuilder LandSurfaceManager | Functional but not cross-checked |

**ACTION NEEDED:** Lighting should use the decompiled AdjustPlanes algorithm. Terrain normals may differ from retail.

## Phase 4 — Networking

| Component | Status | Source | Notes |
|-----------|--------|--------|-------|
| ISAAC keystream | ✅ | ACE golden vectors | Clean-room reimplementation, verified |
| Packet framing / Hash32 / CRC | ✅ | ACE + holtburger cross-check | Byte-compatible with live ACE |
| Fragment assembly | ✅ | ACE + holtburger | Sequence-keyed (corrected from ID-keyed) |
| LoginRequest builder | ✅ | ACE + holtburger | Live-tested |
| ConnectResponse | ✅ | holtburger | Port 9001, 200ms delay |
| CharacterList parser | ✅ | ACE | Live-tested |
| CharacterEnterWorld | ✅ | holtburger | Live-tested |
| DddInterrogationResponse | ✅ | holtburger | Language=1, lists=[] |
| LoginComplete | ✅ | holtburger | Fires on PlayerCreate |
| CreateObject parser | ⚠️ | ACE | Partial — skips many PhysicsData fields |
| ACK pump | ✅ | holtburger | Per-packet, piggybacked |
| MoveToState builder | ✅ | holtburger player/types.rs:237-245 | Sequence counters tracked from CreateObject/UpdatePosition/PlayerTeleport |
| AutonomousPosition | ⚠️ | holtburger | Missing sequence counters |

**ACTION NEEDED:** CreateObject parser should extract all PhysicsData fields. Movement messages need proper sequence counters.

## Phase 5 — Character Appearance

| Component | Status | Source | Notes |
|-----------|--------|--------|-------|
| AnimPartChanges | ⚠️ | ACE CreateObject format | Works but PackedDwordOfKnownType was buggy initially |
| TextureChanges | ⚠️ | ACE + acdream investigation | Surface→OrigTextureId chain correct |
| SubPalettes | ✅ | ACViewer IndexToColor | Faithful port with range offset |
| ObjScale | ⚠️ | ACE PhysicsDescriptionFlag | Works |

## Phase 6 — Animation

| Component | Status | Source | Notes |
|-----------|--------|--------|-------|
| MotionResolver.GetIdleCycle | ⚠️ | ACE MotionTable | Cycle key encoding verified |
| MotionResolver.GetIdleFrame | ⚠️ | ACE MotionTable | Single-frame extraction |
| AnimationSequencer (rewritten) | ✅ | Decompiled FUN_005261D0 pseudocode | Faithful port of update_internal |
| AnimationSequencer.SetCycle | ✅ | Decompiled + ACE MotionInterp | adjust_motion from ACE:394-428 |
| AnimationSequencer reverse playback | ✅ | Decompiled FUN_005267E0 | Fixed frame-swap bug |
| AnimationSequencer.SlerpRetailClient | ✅ | Decompiled FUN_005360d0 | Weight-validation fallback |

## Phase A — Foundation (Streaming, Culling, Net Thread)

| Component | Status | Source | Notes |
|-----------|--------|--------|-------|
| StreamingRegion | N/A | acdream-specific | Not AC-specific |
| FrustumCuller | N/A | Standard graphics algorithm | Not AC-specific |
| LandblockStreamer | N/A | acdream-specific | Sync mode due to DatCollection thread safety |
| Net receive thread | N/A | acdream-specific | Channels-based |

## Phase B — Movement

| Component | Status | Source | Notes |
|-----------|--------|--------|-------|
| PhysicsBody (Euler integration) | ✅ | Decompiled FUN_005111d0 | Gravity, friction, velocity clamping |
| PhysicsBody.calc_acceleration | ✅ | Decompiled FUN_00511420 | -9.8 gravity |
| PhysicsBody.calc_friction | ✅ | Decompiled FUN_0050f940 | Ground normal + pow decay |
| MotionInterpreter | ✅ | Decompiled FUN_00529390 etc | 10 methods ported |
| CollisionPrimitives | ✅ | Decompiled chunk_00530000.c | 9 functions ported |
| TerrainSurface.SampleZ | ✅ | ACME ClientReference + decompiled | Triangle-aware barycentric, conformance-tested |
| TerrainSurface split formula | ✅ | Decompiled + AC2D + ACME | Both formulas produce identical results |
| PlayerMovementController | ⚠️ | Mix of ported + custom | Uses ported PhysicsBody but terrain collision is simplified |
| Indoor transitions | ❌ | Disabled | CellPortal detection needs decompiled find_transit_cells |
| Jump physics | ⚠️ | ACE MovementSystem.GetJumpHeight | Formula from ACE, not decompiled |

**ACTION NEEDED:** Indoor transitions should be ported from decompiled CEnvCell functions. Jump needs decompiled verification.

---

## Summary

| Status | Count | Percentage |
|--------|-------|------------|
| ✅ VERIFIED (decompiled/ACME) | 31 | 53% |
| ⚠️ REFERENCE (ACE/ACViewer/holtburger) | 20 | 34% |
| ❌ GUESSED (no reference) | 3 | 5% |
| N/A (not AC-specific) | 5 | 8% |

**Key gaps to address:**
1. Lighting (AdjustPlanes) — currently guessed
2. Indoor transitions — disabled, needs decompiled port
3. SceneryGenerator LCG — needs decompiled verification
4. CreateObject parser — incomplete PhysicsData extraction
5. Movement sequence counters — missing from outbound messages
