suaveplan/openspec/changes/enterprise-gaming-universe/proposal.md

Why

The existing @suaveplan/day-night package uses hardcoded sinusoidal sun arcs, 30-day moon cycles, and preset lighting tables. It is not physically derived, not extensible to other planets, and conflates game-clock concerns with rendering concerns. This change introduces two gaming-layer packages that consume the astronomical core from @suaveplan/universe to provide a configurable game clock and physically-derived environment lighting.

What Changes

• Retire @suaveplan/day-night — replaced by @suaveplan/gaming-universe (game clock + events) and @suaveplan/gaming-environment-lighting (sky colour + gameplay modifiers).
• Create @suaveplan/gaming-universe — wraps UniverseClient with configurable N× game clock via @suaveplan/timing's AsyncScheduler, emitting season/sunrise/eclipse events through @suaveplan/events.
• Create @suaveplan/gaming-environment-lighting — replaces hardcoded day-night presets with Rayleigh/Mie scattering sky colour, twilight star visibility thresholds, multi-satellite moonlight, and continuous gameplay modifiers derived from ambient light.

BREAKING: @suaveplan/day-night is retired — consumers must migrate to @suaveplan/gaming-universe + @suaveplan/gaming-environment-lighting.

Capabilities

New Capabilities

• gaming-universe: Game-clock astronomical wrapper — N× time scale, event emission, and scene queries at game time.
• gaming-environment-lighting: Physically-derived environment lighting — sky colour, star visibility, moonlight, and gameplay modifiers.

Modified Capabilities

• gaming-day-night: Retired — all requirements absorbed by gaming-universe and gaming-environment-lighting. No spec delta; capability removed on archive.

Impact

• New packages: 2 packages in universal/gaming.
• Dependency graph: universe → gaming-universe → gaming-environment-lighting.
• Prerequisite: @suaveplan/universe and its downstream providers (solar-system, stars, tides) must be implemented first.
• Downstream consumers: Any package depending on @suaveplan/day-night must migrate.
• Deferred integrations: R3F / Three.js rendering integration, multiplayer game time sync, @suaveplan/weather integration are explicitly out of scope.