# Biome And Natural Resource Generation Plan

Agrarian needs Earth-aware tile generation, not hand-authored placeholder maps.
Every 1 km tile should derive its biome and natural resources from real-world
environmental signals, then place removable and persistent objects that behave
like real natural resources.

## Biome Selection Inputs

Each tile should eventually derive biome weights from:

- latitude
- elevation
- slope and aspect
- rainfall
- seasonal temperature swing
- ocean proximity
- prevailing wind
- ocean currents
- rain-shadow effects
- soil type
- drainage
- river, lake, wetland, and coast proximity
- land-use history when available

## Layered Generation

1. Climate engine: produces temperature, rainfall, seasonality, and weather
   pressure.
2. Biome generator: assigns weighted macro/regional/local biome blends.
3. Ecology layer: chooses plant communities, wildlife, disease pressure, soil
   behavior, and water availability.
4. Resource layer: places trees, shrubs, grasses, rocks, water bodies, edible
   plants, fuel, fiber, and old human-made objects.
5. Human layer: derives agriculture suitability, settlement pressure, trade
   value, travel difficulty, and cultural/economic implications.

## Biome Output Shape

Avoid hard borders. A tile should produce weighted blends such as:

- `70% coastal scrub`
- `20% riparian woodland`
- `10% seasonal marsh`

Those weights drive asset selection, density, color variation, seasonality, and
resource availability.

## Persistent Natural Resources

Every removable world object should have durable state:

- unique tile-local resource id
- resource type
- species or object profile
- transform
- growth stage
- health
- age
- quantity remaining
- removed/depleted timestamp
- player/planted/natural origin
- respawn or regrowth policy
- last simulation timestamp

## Removal And Regrowth Rules

- Trees, shrubs, rocks, puddles, lakes, ruins, shelters, and large props should
  not silently pop back after removal.
- Player-removed trees and shrubs stay removed unless replanted or naturally
  reseeded over realistic in-game time.
- Stumps, deadwood, brush piles, and disturbed ground should be valid aftermath
  states rather than instant deletion.
- Water bodies are removable only through believable terrain/drainage changes,
  drought, construction, or simulation systems.
- Edible plants, grasses, brush, and fiber resources can replenish, but only on
  realistic seasonal timelines and only when biome, weather, grazing, and human
  use allow it.
- Player-planted resources use explicit planting/cultivation rules rather than
  random respawn.

## First Implementation Slice

1. Add tile biome profile data assets or JSON metadata for Ground Zero.
2. Register asset sets by biome weight: terrain, trees, shrubs, grasses, rocks,
   water, wildlife, reclaimed props.
3. Convert placed foliage/resource proxies into persistent resource records.
4. Add removal state and save/load durability for trees and shrubs first.
5. Add slow regrowth/reseeding simulation for grasses/shrubs/trees.
6. Extend to water bodies, edible plants, rocks, and reclaimed objects.

## Investor Relevance

This system should make new tiles feel recognizable without hand-sculpting each
one. A Pacific coastal tile, a prairie tile, a boreal tile, and a river valley
tile should choose different assets, resource densities, travel difficulty, and
survival pressures automatically.