The blueprint has carried water since task 03 -- WBID per-pixel body id,
WBTB body table, WSRF per-pixel surface level. Nothing ever drew it. Now
the runtime does. No new water data: the blueprint is the authority on
where water is and at what level, and this only reads it.
WHY WATER IS ITS OWN MESH, not a block in the terrain field. The terrain
is a Marching-Cubes iso-surface over ChunkData.Densities. Writing WATER
into that field would not lay a sheet on top of the seabed -- it would
move the iso-surface, fusing the sea into the terrain as if it were solid
ground. A second surface is the only way water can sit at ITS level
independent of the ground under it. So ChunkRenderer builds a water
MeshInstance3D as a child of the chunk's terrain mesh.
TRANSPARENCY IS SHIPPED, NOT DEFERRED (Step 2.4's cheap branch). Because
water is a distinct MeshInstance3D it carries its own StandardMaterial3D,
so alpha is one flag and Godot sorts transparent surfaces after opaque
ones by itself. Zero mesher changes. Alpha runs 0.62 shallow -> 0.97 deep,
so the shelved coast stays readable and open ocean closes up.
WHICH DATA DROVE IT: WSRF for the level (per-pixel, quantised to 1/32768
raw ~ 7.7 mm, far under the 1 m voxel, and no table lookup), WBID for
presence (it is the water stage's own classification output -- the same
set the biome grid's Ocean/Lake pixels form by construction), WBTB as the
fallback when a column is flagged wet but carries the WSRF no-water
sentinel. A body the table does not know leaves the column DRY rather
than guessing a level.
Details worth keeping:
- Water Y uses Constants.HEIGHT_SCALE, the SAME mapping as the terrain
surface, named so the sheet and the seabed cannot drift apart if the
vertical band is ever retuned.
- Depth for shading comes from BLUEPRINT heights, not rendered geometry:
the terrain render clamps its floor at Y=2, so every deep-ocean column
would otherwise read as one flat ~36 m and the gradient would die
exactly where the ocean gets interesting.
- A cell is drawn if ANY corner is wet, flat at the highest wet level.
Drawing onto a partly-dry cell is deliberate -- it carries the sheet
under the shoreline where the opaque terrain hides it. Only-fully-wet
cells retreat the waterline a metre and leave a dry gap around every
coast and lake.
- Non-metallic, roughness 0.35: the scene environment is minimal, and a
metallic surface reads near-black when there is nothing to reflect.
BlockRegistry gains WATER (id 11). Wire-safe: block IDs are never
serialized -- the blueprint's section table stores heights, biome ordinals
and water data, never block IDs, and chunks are not persisted yet.
MEASURED on seed 1825907253: 241,415 water columns across 454 of 4096
chunks; surface Y 37.6..37.6 m (flat, = 0.15 x 251 -- the flat sea model,
rendered); depth to 32.3 m, matching an independent read of the blueprint
exactly. Both an ocean and a lake fall in the default view.
NO REGRESSION to the 2D pipeline, verified section by section: a
regeneration of the working seed is byte-identical to task 12's run in
TCRV, TDTL, HGTS, BIOM, WBID, WBTB, WSRF, TOWN and all four road
sections; only PRMS differs, and only in its write timestamp. All four
snapshot PNGs md5-identical.
No storms, no waves, no animation, no flow -- water at rest. Those are C2+.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
All four road tiers now carve into the 3D world. Rugged and Trail were
generated, exported and parsed all along, but nothing ever consumed them —
which is why county roads visible on the 2D map did not exist in 3D.
Tier identity is now carried into the carve via a RoadSegment struct, so each
tier gets its own width, shoulder and grade-smoothing from one tunable block in
Constants: highways widest and holding a grade, trails narrow and hugging the
land. Rugged and Trail surface as dirt rather than asphalt.
Because tiers now have different reach, nearest-by-distance was no longer a
sound way to pick the governing road — a nearby footpath could shadow a highway
whose shoulder still covered the column. The carve now considers only roads
whose shoulder actually reaches, and takes the closest of those.
The per-chunk cull pad is derived from the widest shoulder plus a margin, so
widening a road cannot silently truncate it at chunk edges.
Untouched: density field, Marching Cubes interpolation/welding, chunk dims,
the .dat contract, the 2D A* generation, and mesher normals.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Vertex colour is now chosen from the true, unrounded surface height and faded
between adjacent materials across a tunable band, instead of switching at one
rounded integer depth. This removes the horizontal contour banding.
Colour path only: density field, Marching Cubes interpolation/welding, chunk
dimensions, the .dat contract and all road logic are untouched. BlockID
classification is unchanged and still drives non-visual use.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
