# OpenSpec Change: enterprise-gaming-r3f-weather

- **Change ID**: enterprise-gaming-r3f-weather
- **Package**: `@suaveplan/r3f-weather`
- **Category**: gaming/scene
- **Target path**: `gaming/scene/r3f-weather`
- **Status**: PROPOSED
- **Date**: 2026-04-24
- **Reference spec**: `/mnt/s/web/suaveplan/enterprise/r3f-weather.md`

---

## Summary

Deliver `@suaveplan/r3f-weather` on the genesis branch from scratch at enterprise quality. The package provides R3F weather rendering: GPU-instanced rain/snow particles driven by `WeatherState` from `@suaveplan/weather`; dynamic `<fog>` density from `weatherState.fogDensity`; lightning flash via PointLight pulse on `weather:lightning` event; surface wetness PBR normal-map overlay applied via material compositing. A `WeatherRenderer` component subscribes to `WeatherSystem` and drives all sub-systems. Genesis adds structured errors, OTel particle-count gauge, and 100% coverage.

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## Available workspace deps

`@suaveplan/error`, `@suaveplan/weather`, `@suaveplan/events`, react, `@react-three/fiber`, `@react-three/drei`, three.

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## Public API surface

```ts
function WeatherRenderer(props: WeatherRendererProps): JSX.Element
// weatherSystem, particleCount, lightningIntensity

function RainParticles(props: RainParticlesProps): JSX.Element
function SnowParticles(props: SnowParticlesProps): JSX.Element
function LightningFlash(props: LightningFlashProps): JSX.Element
function FogLayer(props: FogLayerProps): JSX.Element
function useWeatherRenderer(): WeatherRenderState
```

---

## File layout

```text
gaming/scene/r3f-weather/
  package.json / tsconfig.json / vitest.config.ts
  src/
    index.ts / error-codes.ts / constants/index.ts
    types/common.ts + md
    components/
      WeatherRenderer/ (tsx + md + test + stories + index)
      RainParticles/ (tsx + md + test + stories + index)
      SnowParticles/ (tsx + md + test + stories + index)
      LightningFlash/ (tsx + md + test + stories + index)
      FogLayer/ (tsx + md + test + stories + index)
    hooks/use-weather-renderer.ts + md + test
  tests/integration.test.ts
```