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@@ -3,5 +3,7 @@ SlaveMatrix/obj/
 2DGAMELIB/bin/
 SlaveMatrix/bin/
 .vs/
+.idea/
+Config.ini
 game_folder/save/*
 /game_folder/save
diff --git a/PLAN.md b/PLAN.md
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+# SlaveMatrix Engine Rewrite Plan
+
+## Goal
+
+Rearchitect the game from a decompiled monolith with hardcoded Japanese string lookups, BinaryFormatter resources, and GDI+ rendering into a moddable, data-driven engine with Vulkan/Silk.NET rendering, YAML sidecar definitions, and SVG vector assets.
+
+## Key Decisions
+
+- **Clean break** from save compatibility (no BinaryFormatter/RenameMap)
+- **Vulkan/Silk.NET** rendering backend
+- **YAML** sidecar data files for body part definitions
+- **Full modding support**: new body parts, races, color schemes, animation states
+- **SVG extraction** for vector graphics data; Vulkan rendering at runtime
+- **Runtime catalog** built from sidecar files at load time
+- **No MigrateKeys** -- resource data will have keys renamed at extraction time, not at runtime
+
+## Current State
+
+- 843 BodyPartClasses with Japanese filenames
+- 13 binary `Obj` resources embedded in `.resx` (5.5MB largest)
+- `MigrateKeys()` runtime key-mutation for 4 of 13 resources (fragile, incomplete)
+- 1,660 unique string keys across all resource lookups
+- BinaryFormatter double-wrapped serialization
+- GDI+ rendering with cardinal splines, GraphicsPath, hit-testing
+- Existing `Ser.ToJson`/`Ser.UnJson` infrastructure (needs fixes for private fields and OrderedDictionary)
+
+## Phase 0: Resource Extraction & Asset Pipeline
+
+### 0.1: Fix JSON Serialization
+
+- Add `JsonConverter<OrderedDictionary<T1,T2>>` for proper dictionary round-tripping
+- Configure `DefaultContractResolver` to include private fields (`Difs.difs`, `Dif.parss`, `Pars.parent`)
+- Fix `ToJsonBytes` to use `PreserveReferencesHandling.All` (match `ToJson`)
+- Test: `ObjLoad()` -> `ToJson()` -> `UnJson()` -> verify rendering is identical
+
+### 0.2: Build Complete Key Map
+
+- Audit ALL `Sta.X["key"]` and `pars["key"]` lookups across all body part classes
+- Build definitive `KeyMap` covering all 155 top-level keys + 1,516 Pars keys
+- Add Pars-level recursive migration to `MigrateKeys()`
+- Apply `MigrateKeys()` to ALL 13 resources (currently only 4 get it)
+
+### 0.3: Write Extraction Console App
+
+- Create `SlaveMatrix.Extract` console project
+- Load all 13 `Obj` from embedded resources
+- Apply complete `MigrateKeys()`
+- Export each `Obj` to JSON file
+- Export body part breakdown (each `Difs` key -> separate file)
+- For SVG export: iterate all `Par` objects, convert cardinal spline to cubic Bezier, write SVG `<path>` elements
+- Export part metadata (joints, connections, color data) as YAML sidecar files
+- Output a catalog of all parts with their connections
+
+### 0.4: Validate Extraction
+
+- Build visual comparison tool: render original vs. extracted -> pixel diff
+- Verify all keys match, all shapes present, all morph variants accounted for
+
+## Phase 1: Engine Foundation
+
+- New .NET 8 solution: `SlaveMatrix.Engine`, `SlaveMatrix.Modding`, `SlaveMatrix.Game`, `SlaveMatrix.AssetTool`
+- Vulkan/Silk.NET renderer: GPU path rendering, fill/stroke, hit-testing
+- YAML part definition schema (connections, variants, colors, joints)
+- Asset loader: scan `Assets/` directories, build runtime `PartCatalog`
+- Morph interpolation between SVG variants
+
+## Phase 2: Character Assembly & Joints
+
+- Explicit joint definitions in YAML (no proximity-based matching)
+- Connection resolution: parent-child graph from catalog
+- Character builder: given race template, assemble character from parts
+- Runtime catalog on startup
+
+## Phase 3: Game Logic Migration
+
+- YAML-based character saves (replace EleD serialization)
+- YAML-driven color palette system (replace `配色指定`/`BodyColorSet`)
+- Pose/animation system (same morph concept, YAML-defined)
+- Port UI
+
+## Phase 4: Modding API
+
+- Mod package format: manifest.yaml + Parts/ + Races/ + Colors/
+- Mod loader: merge catalogs, validate connections
+- Hot reload during development
+
+## Phase 5: Polish & Release
+
+- Build pipeline: MSBuild targets for asset packing
+- Performance: GPU instancing, spatial partitioning
+- Visual regression tests
+
+## Resource Architecture
+
+### Current (Binary)
+
+```
+Resources.resx -> byte[] -> BinaryFormatter(BinaryFormatter(Obj)) -> Obj
+                     Obj.Difss keys are Japanese
+                     MigrateKeys() renames some keys at runtime (fragile)
+```
+
+### Target (YAML + SVG)
+
+```
+Assets/
+  Parts/torso/torso.yaml         <- part definition
+  Parts/torso/torso_base.svg      <- X0Y0 variant
+  Parts/torso/torso_morph1.svg    <- X1Y0 variant
+  Colors/skin_tones.yaml          <- color palette
+  Races/human.yaml                <- race template
+  Catalog.yaml                    <- auto-generated index
+
+Game loads YAML+SVG at runtime, no embedded binary resources needed.
+Modders add directories under Assets/Parts/ to add new parts.
+```
+
+## Rendering Architecture
+
+### Current (GDI+)
+
+- `System.Drawing.Graphics.FillPath/DrawPath` for fills and strokes
+- `GraphicsPath.AddCurve(points, tension)` for cardinal splines
+- Separate hit-test pass with unique colors per `Par`
+- `Difs.ValueX/ValueY` controls morph interpolation (discrete variant selection)
+
+### Target (Vulkan/Silk.NET)
+
+- GPU path rendering: tessellate cubic Bezier curves into triangles
+- Separate hit-test pass: render with unique colors to offscreen buffer, read pixel
+- Morph interpolation: blend control point positions between SVG variants
+- YAML-driven pose system replaces hardcoded `Difs` index selection
+
+## Data Format: YAML Part Definition
+
+```yaml
+id: BaseHair
+category: hair
+parent: Head
+connections:
+  - name: top_left
+    joint: top_left
+  - name: top_right
+    joint: top_right
+  - name: front
+    joint: front_hair
+  - name: back
+    joint: back_hair
+  - name: side_left
+    joint: side_hair_left
+  - name: side_right
+    joint: side_hair_right
+variants:
+  - x: 0
+    y: 0
+    svg: base_hair_x0y0.svg
+morph_x: 1
+morph_y: 1
+colors:
+  hair: { palette: hair, field: HairCD }
+```
+
+## Data Format: YAML Race Template
+
+```yaml
+id: human
+parts:
+  torso: { variant: human, morph_x: 0.5, morph_y: 0.3 }
+  head: { variant: human }
+  hair: { variant: long }
+  left_arm: { variant: human }
+  right_arm: { variant: human }
+  left_leg: { variant: human }
+  right_leg: { variant: human }
+colors:
+  skin: { palette: skin_tones, index: 0 }
+  hair: { palette: hair_colors, index: 3 }
+```
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