Galaxy Space Flight

Make a three.js game/app that generates a fully 3D, procedurally generated SOLAR SYSTEM you can explore end-to-end: fly a spaceship through space, land on different planets, exit the ship and walk around in first-person, re-enter the ship, take off, and travel to other planets.

Solar system:
- Procedurally generate a star at the center and multiple planets (e.g., 5–10), each with:
  - Unique size and look
  - Different terrain style parameters (roughness, mountain frequency, ocean level, temperature/moisture profiles)
  - Optional moons for some planets (procedurally generated as well)
- Planets should orbit the star smoothly.
- Space should feel large: planets are separated by big distances, but navigation should remain playable.

Spaceship gameplay (space flight):
- You control a spaceship in 3D space:
  - Mouse-look to aim/turn + WASD thrust/strafe (or similar)
- Show a minimal HUD: speed, altitude above nearest body, and current target planet name/distance.
- The ship must not be able to clip into planets.

Hyperdrive:
- Holding Shift while in SPACE (not in atmosphere) charges a hyperdrive.
- After holding Shift for a few seconds continuously, the ship enters hyperdrive:
  - Greatly increases travel speed toward the current travel direction (or selected target planet)
  - Add a simple visual cue (star streaks, subtle warp effect, etc.)
- Hyperdrive restrictions:
  - Cannot be activated when inside a planet’s atmosphere (define atmosphere as below a set altitude threshold).
  - If the ship enters atmosphere, hyperdrive immediately disengages.

Atmosphere / re-entry / landing:
- Each planet has an atmosphere threshold altitude.
- Landing:
  - Allow landing anywhere reasonably flat (or use a simple landing assist).
  - Detect ground contact and switch ship state to “landed”.

On-foot gameplay (first person):
- When the ship is landed, you can exit the ship and switch to a first-person character controller:
  - WASD + mouse-look, jump, gravity, ground collision
- The character must not be able to clip through terrain and should walk naturally on a spherical planet.
- Allow returning to the ship when close to it (press E / interact) to re-enter and switch back to ship controls.
- Taking off:
  - From “landed”, a takeoff control lifts the ship upward, then transitions back to atmosphere flight.

Procedural planets (terrain + LOD):
- Every planet uses procedural spherical terrain:
  - Height variation (mountains/hills/plains), plus an ocean level with visible water
  - Biomes based on latitude, altitude, and moisture (desert/grassland/forest/tundra/snow etc.)
  - Shorelines/beaches where land meets ocean
  - Optional vegetation (trees) in biome-appropriate regions with natural density variation
- Use a level-of-detail system per planet so it stays performant:
  - From far away: low-detail sphere
  - As you approach: higher-detail patches/tiles only around the camera/player
  - Must be seamless, with no obvious popping or cracks
  - Terrain detail increases smoothly down to ground-level exploration
- Vegetation and small details should fade out with distance/LOD.

Atmosphere & clouds:
- Add an atmosphere effect around each planet (thin scattering-style rim is fine).
- Add a cloud layer for planets that have clouds:
  - Wraps the planet and is animated (slowly moving/rotating)
  - Visible both from space and near the surface

Everything should be procedurally generated (no external assets required).
Keep visuals simple but coherent and stable across space flight, landing, and on-foot exploration.