feat: height-redistribution curve, gated + biome-invariant (terrain-water task 05)

HeightCurve (pure static, D-035): calibrated monotonic piecewise map —
identity at/below sea 0.15; ease-out toe to the orange ceiling 0.206
(75% coverage, knot t1=P75=0.628736 from batch-04's pooled flat-sea
land CDF, 340.6M samples); linear rise to red 0.27 (t2=P90); smooth
shoulder to the 50m plateau shelf 0.3492 (t3=P93); near-flat plateau
step (t4=P96); accelerating spike to the 220m peak cap 1.0265; linear
tail past the calibrated max. Strict monotonicity asserted numerically
at startup, loud throw on violation.

Applied in GenerateTopography AFTER noise+falloff+Trench, BEFORE the
crater carve (carve cuts curved terrain; rim/bowl untouched by the
curve). Biome oracle mechanism: a retained uncurved classify heightmap
(alias of _heightMap when off, zero cost) feeds biome rules, both
flood fills, and the shared water predicates — classification is
curve-invariant by construction. Towns/roads/diagnostics/exported
heights use curved terrain; town positions may legitimately move.

Config gate TerrainCurve: "off"|"v1" (default v1), unknown values
rejected loudly.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
This commit is contained in:
Stewart Howe 2026-08-07 15:22:53 -04:00
parent 9e55324668
commit 67868638be
3 changed files with 159 additions and 11 deletions

View file

@ -26,6 +26,12 @@ namespace IslaApocalypse.Core // Change this if your namespace is different
public static string SeaLevelModel = "flat";
public static float SeaLevelValue = 0.15f;
// Height-redistribution curve (task 05, graduation M-7): "v1" applies the
// calibrated storm-ladder curve to above-sea terrain (see HeightCurve.cs);
// "off" is the raw legacy profile. Biome classification is curve-invariant
// by construction either way. Default: v1.
public static string TerrainCurve = "v1";
public static void LoadConfig()
{
string path = "res://ServerConfig.json";
@ -95,6 +101,16 @@ namespace IslaApocalypse.Core // Change this if your namespace is different
SeaLevelValue = (float)data["SeaLevelValue"];
}
// Extract the terrain-curve gate
if (data.ContainsKey("TerrainCurve"))
{
string curve = (string)data["TerrainCurve"];
if (curve == "off" || curve == "v1")
TerrainCurve = curve;
else
GD.PrintErr($"[ConfigManager] Unknown TerrainCurve '{curve}'. Keeping '{TerrainCurve}'.");
}
switch (profile)
{
case "4K":