Initial Commit

openspec/changes/enterprise-gaming-r3f-terrain/proposal.md

@@ -0,0 +1,57 @@
+# OpenSpec Change: enterprise-gaming-r3f-terrain
+
+- **Change ID**: enterprise-gaming-r3f-terrain
+- **Package**: `@suaveplan/r3f-terrain`
+- **Category**: gaming/scene
+- **Target path**: `gaming/scene/r3f-terrain`
+- **Status**: PROPOSED
+- **Date**: 2026-04-24
+- **Reference spec**: `/mnt/s/web/suaveplan/enterprise/r3f-terrain.md`
+
+---
+
+## Summary
+
+Deliver `@suaveplan/r3f-terrain` on the genesis branch from scratch at enterprise quality. The package provides procedural terrain with chunked LOD for React Three Fiber. A `TerrainSystem` divides world space into equal-size chunks; each chunk generates a height-mapped `PlaneGeometry` using a pluggable noise function (simplex, perlin, or caller-supplied); LOD is managed by camera distance — near chunks use high subdivision, far chunks use low. Biome tinting (grass/rock/snow) is applied via vertex color or shader. Genesis adds Zod chunk config schemas, structured errors, OTel chunk-load histogram, and 100% coverage.
+
+---
+
+## Available workspace deps
+
+`@suaveplan/error`, `@suaveplan/types`, `@suaveplan/events`, `@suaveplan/spatial-hash`, react, `@react-three/fiber`, `@react-three/drei`, three.
+
+---
+
+## Public API surface (key exports)
+
+```ts
+function Terrain(props: TerrainProps): JSX.Element
+// - chunkSize, worldSize, maxLOD, heightScale, noiseFn, biomeMap
+
+function useTerrainHeight(x: number, z: number): number   // sample height at world position
+```
+
+---
+
+## File layout
+
+```text
+gaming/scene/r3f-terrain/
+  package.json / tsconfig.json / vitest.config.ts
+  src/
+    index.ts
+    error-codes.ts
+    constants/index.ts
+    types/common.ts + md
+    core/
+      terrain-system/ (ts + md + types + test + index)
+      chunk-manager/ (ts + md + types + test + index)
+      lod-controller/ (ts + md + types + test + index)
+    components/
+      Terrain/ (tsx + md + test + stories + index)
+      TerrainChunk/ (tsx + md + test + stories + index)
+    utils/
+      noise.ts + md + test
+      height-sample.ts + md + test
+  tests/integration.test.ts
+```