Add Terrain and Water

Terrain-and-Water.md

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+# Terrain and Water
+
+This page defines how contributors should build terrain and shorelines for NETFISHING.
+
+## Do not create one giant island mesh
+
+The complete world should not be one enormous Blender mesh.
+
+Prefer one terrain mesh per major region:
+
+- Village
+- Starter Pond
+- River
+- Lake
+- Marsh
+- Coast
+
+This allows each region to be:
+
+- Replaced independently
+- Edited without exporting the whole world
+- Assigned separate collision
+- Worked on by different contributors
+- Rearranged in Godot
+
+## What terrain may include
+
+A regional terrain mesh may include:
+
+- Broad land shape
+- Shoreline
+- Hills
+- Slopes
+- Main path shape
+- Pond or lake basin
+- Underwater slopes
+- Visible seabed
+
+Terrain should not include:
+
+- Water surfaces
+- Docks
+- Bridges
+- Trees
+- Rocks
+- Buildings
+- Signs
+- Fishable-water areas
+- Recovery triggers
+- Safe respawn points
+- Interaction areas
+
+Those remain separate in Godot or separate reusable assets.
+
+## Water ownership
+
+Blender owns:
+
+- Shoreline shape
+- Bank shape
+- Underwater slopes
+- Beaches
+- Visible seabed
+- Water-body openings
+
+Godot owns:
+
+- Water surface
+- Water shader or material
+- Fishable-water volume
+- Recovery trigger
+- Water animation
+- Gameplay behavior
+
+Do not export primary playable water as part of the terrain GLB.
+
+## Water reference plane
+
+A temporary reference plane may be used in Blender.
+
+Recommended name:
+
+    REF_WaterLevel
+
+Exclude it from the final export.
+
+Suggested local vertical reference:
+
+    Land walking surface: Z = 0
+    Water reference: Z = 0.1 to 0.2
+    Shallow shoreline shelf: Z = -0.3 to -1
+    Main seabed: Z = -4 to -6
+
+Do not place a flat solid slab immediately beneath the water surface.
+
+## Region origins
+
+Model regional terrain around a predictable local origin.
+
+Recommended convention:
+
+- Region center near `0,0,0`
+- Ground near `Z = 0`
+- Water reference near `Z = 0.2`
+- Seabed between `Z = -4` and `Z = -6`
+
+Godot places the region at its final world position.
+
+Do not bake the complete world’s Godot coordinates into every regional Blender file.
+
+## Terrain collision
+
+Terrain collision should be simpler than the visual mesh.
+
+A terrain Blender file may contain:
+
+- `StarterPondTerrain_Visual`
+- `StarterPondTerrain_Collision`
+
+The collision mesh should:
+
+- Remove small bumps
+- Remove decorative details
+- Use broad slopes
+- Avoid tiny holes
+- Avoid narrow triangles
+- Avoid invisible lips
+- Follow the visible shoreline reasonably closely
+
+Do not use detailed terrain geometry directly as collision without testing it in Godot.
+
+## Region composition in Godot
+
+A region will typically contain:
+
+    StarterPondRegion
+    ├── TerrainVisual
+    ├── TerrainCollision
+    ├── Water
+    ├── FishingRegion
+    ├── WaterRecovery
+    ├── SafeRespawns
+    └── Props
+
+Contributors normally provide visual models and requested collision.
+
+Gameplay nodes are configured in Godot.