Initial Commit

openspec/changes/enterprise-gaming-bone-mapping/proposal.md

@@ -0,0 +1,152 @@
+# OpenSpec Change: enterprise-gaming-bone-mapping
+
+- **Change ID**: enterprise-gaming-bone-mapping
+- **Package**: `@suaveplan/bone-mapping`
+- **Category**: gaming/rigs
+- **Target path**: `gaming/rigs/bone-mapping`
+- **Status**: PROPOSED
+- **Date**: 2026-04-24
+- **Reference spec**: `/mnt/s/web/suaveplan/enterprise/bone-mapping.md`
+
+---
+
+## Summary
+
+Deliver `@suaveplan/bone-mapping` on the genesis branch from scratch at enterprise quality. The package provides skeleton detection, bone matching by fuzzy name heuristics, and retargeting math — the foundation for animation clip transfer between different character rigs. `detectSkeleton` classifies a bone hierarchy as Mixamo/Humanoid/Custom; `matchBones` pairs source and target bones using edit-distance scoring with anatomical weight boosts; `retargetPose` transforms local-space bone rotations from source binding pose to target binding pose using the standard retargeting matrix `R_target = T_offset * R_source * T_offset^-1`. Genesis adds Zod schemas, structured errors, and property-based correctness tests.
+
+---
+
+## Current-state audit (genesis)
+
+Package does not exist on genesis yet — fresh build.
+
+---
+
+## Available workspace deps on genesis
+
+| Package | Role |
+|---|---|
+| `@suaveplan/error` (`workspace:^`) | `BoneMappingError`; `BONE_MAP.*` codes |
+| `@suaveplan/types` (`workspace:^`) | Shared primitives |
+| `zod` (`catalog:forms`) | Bone map result schemas |
+| `@opentelemetry/api` (`catalog:observability`) | Detection + match spans |
+
+---
+
+## Public API surface
+
+```ts
+type SkeletonType = 'mixamo' | 'humanoid' | 'custom'
+
+function detectSkeleton(bones: BoneDescriptor[]): SkeletonType
+
+function matchBones(
+  source: BoneDescriptor[],
+  target: BoneDescriptor[],
+  options?: MatchOptions
+): BoneMatch[]
+
+interface MatchOptions {
+  minConfidence?: number     // 0–1, default 0.5
+  preferExact?: boolean
+}
+
+interface BoneMatch {
+  sourceBone: string
+  targetBone: string
+  confidence: number
+}
+
+function retargetPose(
+  sourcePose: BonePose[],
+  boneMatches: BoneMatch[],
+  sourceBindPose: BonePose[],
+  targetBindPose: BonePose[]
+): BonePose[]
+
+function buildRetargetMatrix(
+  sourceBind: Quat,
+  targetBind: Quat
+): RetargetMatrix
+
+interface RetargetMatrix {
+  apply(rotation: Quat): Quat
+}
+
+interface BoneDescriptor {
+  name: string
+  parentIndex: number
+  localPosition: Vec3
+  localRotation: Quat
+}
+
+interface BonePose {
+  boneIndex: number
+  position: Vec3
+  rotation: Quat
+}
+```
+
+### Error codes
+
+```ts
+type BoneMapErrorCode =
+  | 'BONE_MAP_NO_BONES'
+  | 'BONE_MAP_MATCH_FAILED'
+  | 'BONE_MAP_RETARGET_FAILED'
+  | 'BONE_MAP_INVALID_BIND_POSE'
+```
+
+---
+
+## New additions for genesis
+
+1. **Fuzzy bone matching** — Levenshtein distance + anatomical keyword boosts (`spine`, `arm`, `leg`, `hand`, `foot`).
+2. **Humanoid auto-detect** — classify skeleton as Humanoid if ≥ 60% of canonical human bone names match within edit distance 2.
+3. **Retarget matrix** — `R_target = T_offset * R_source * T_offset^-1` where `T_offset = target_bind * inverse(source_bind)`.
+
+---
+
+## File layout
+
+```text
+gaming/rigs/bone-mapping/
+  package.json
+  tsconfig.json
+  vitest.config.ts
+  src/
+    index.ts
+    error-codes.ts
+    constants/index.ts
+    types/common.ts
+    types/common.md
+    core/
+      detect/
+        detect.ts
+        detect.md
+        detect.test.ts
+        index.ts
+      match/
+        match.ts
+        match.md
+        match.test.ts
+        index.ts
+      retarget/
+        retarget.ts
+        retarget.md
+        retarget.types.ts
+        retarget.test.ts
+        index.ts
+    utils/
+      quat-math.ts
+      quat-math.md
+      quat-math.test.ts
+  tests/
+    property.test.ts
+```
+
+---
+
+## Impact
+
+**Downstream**: `@suaveplan/mixamo` imports `detectSkeleton` and `retargetPose`; `@suaveplan/ik-solver` uses quaternion math from utils. Prerequisites: `@suaveplan/error`, `@suaveplan/types`.