feat: rebuild the nightdrive road and terrain

tests/unit/scene-resources.test.ts

@@ -155,9 +155,33 @@ describe('scene render quality', () => {
     const medium = renderQualityFor('medium', 3, false);
     const low = renderQualityFor('low', 3, false);
 
-    expect(high).toEqual({ pixelRatio: 1.5, terrainSegments: 96, particleCount: 384, postEffects: true });
-    expect(medium).toEqual({ pixelRatio: 1.5, terrainSegments: 64, particleCount: 192, postEffects: true });
-    expect(low).toEqual({ pixelRatio: 1.25, terrainSegments: 32, particleCount: 64, postEffects: false });
+    expect(high).toEqual({
+      pixelRatio: 1.5,
+      roadSegments: 192,
+      terrainSegments: 96,
+      terrainOctaves: 3,
+      particleCount: 384,
+      streakCount: 48,
+      postEffects: true,
+    });
+    expect(medium).toEqual({
+      pixelRatio: 1.5,
+      roadSegments: 144,
+      terrainSegments: 64,
+      terrainOctaves: 2,
+      particleCount: 192,
+      streakCount: 28,
+      postEffects: true,
+    });
+    expect(low).toEqual({
+      pixelRatio: 1.25,
+      roadSegments: 96,
+      terrainSegments: 32,
+      terrainOctaves: 1,
+      particleCount: 64,
+      streakCount: 12,
+      postEffects: false,
+    });
   });
 
   it('caps mobile and tablet pixel ratio at 1.5 even for High', () => {

tests/unit/world-models.test.ts

@@ -0,0 +1,164 @@
+import { describe, expect, it } from 'vitest';
+import * as THREE from 'three';
+import type { EnvironmentChapter } from '@/journey/types';
+import { renderQualityFor } from '@/scene/render-quality';
+import { SceneResourceBag } from '@/scene/resources';
+import {
+  CHAPTER_PALETTES,
+  createMutableChapterPalette,
+  writeChapterPalette,
+} from '@/scene/world/palette';
+import { createRoad } from '@/scene/world/road';
+import { createTerrain } from '@/scene/world/terrain';
+
+describe('procedural world models', () => {
+  it('scales geometry and atmosphere work monotonically by live quality tier', () => {
+    const high = renderQualityFor('high', 3, false);
+    const medium = renderQualityFor('medium', 3, false);
+    const low = renderQualityFor('low', 3, false);
+
+    expect(high.roadSegments).toBeGreaterThan(medium.roadSegments);
+    expect(medium.roadSegments).toBeGreaterThan(low.roadSegments);
+    expect(high.terrainSegments).toBeGreaterThan(medium.terrainSegments);
+    expect(medium.terrainSegments).toBeGreaterThan(low.terrainSegments);
+    expect(high.streakCount).toBeGreaterThan(low.streakCount);
+    expect(low.postEffects).toBe(false);
+  });
+
+  it('builds a shader road whose motion is entirely uniform-driven', () => {
+    const resources = new SceneResourceBag();
+    const road = createRoad(resources, renderQualityFor('high', 1, false));
+    const surface = road.group.getObjectByName('road-surface') as ShaderRenderable;
+
+    expect(surface).toBeInstanceOf(THREE.Mesh);
+    expect(surface.geometry.index).not.toBeNull();
+    expect(surface.geometry.getAttribute('position').count).toBeGreaterThan(1_000);
+    expect(surface.material.uniforms).toMatchObject({
+      uDistance: { value: 0 },
+      uSpeed: { value: 0 },
+      uAcceleration: { value: 0 },
+    });
+    expect(surface.material.fragmentShader).toContain('centerLane');
+    expect(surface.material.fragmentShader).toContain('outerEdge');
+
+    const positionArray = surface.geometry.getAttribute('position').array;
+    const before = resources.snapshot();
+    for (let index = 0; index < 300; index += 1) {
+      road.update(index * 0.5, 0.65, 0.4);
+    }
+
+    expect(resources.snapshot()).toEqual(before);
+    expect(surface.geometry.getAttribute('position').array).toBe(positionArray);
+    expect(surface.material.uniforms.uDistance?.value).toBe(149.5);
+    expect(surface.material.uniforms.uSpeed?.value).toBe(0.65);
+    expect(surface.material.uniforms.uAcceleration?.value).toBe(0.4);
+    resources.dispose();
+  });
+
+  it('builds one wide indexed line terrain with a flat road-center mask', () => {
+    const resources = new SceneResourceBag();
+    const terrain = createTerrain(resources, renderQualityFor('medium', 1, false));
+    const lines = terrain.group.getObjectByName('terrain-lines') as ShaderRenderable;
+
+    expect(lines).toBeInstanceOf(THREE.LineSegments);
+    expect(lines.geometry.index).not.toBeNull();
+    lines.geometry.computeBoundingBox();
+    expect(lines.geometry.boundingBox).not.toBeNull();
+    expect(
+      (lines.geometry.boundingBox?.max.x ?? 0) - (lines.geometry.boundingBox?.min.x ?? 0),
+    ).toBeGreaterThan(120);
+
+    const roadMask = lines.geometry.getAttribute('roadMask');
+    expect(roadMask).toBeDefined();
+    const maskValues = Array.from(roadMask.array as ArrayLike<number>);
+    expect(Math.min(...maskValues)).toBe(0);
+    expect(Math.max(...maskValues)).toBeGreaterThan(0.99);
+    expect(lines.material.uniforms).toMatchObject({
+      uDistance: { value: 0 },
+      uSpeed: { value: 0 },
+      uRouteProgress: { value: 0 },
+    });
+    expect(lines.material.vertexShader).toContain('multiOctaveNoise');
+
+    const indexArray = lines.geometry.index?.array;
+    const positionArray = lines.geometry.getAttribute('position').array;
+    const lowColor = lines.material.uniforms.uLowColor?.value;
+    const highColor = lines.material.uniforms.uHighColor?.value;
+    const before = resources.snapshot();
+    for (let index = 0; index < 300; index += 1) {
+      terrain.update(index * 0.4, 0.7, 'builds', index / 299);
+    }
+
+    expect(resources.snapshot()).toEqual(before);
+    expect(lines.geometry.index?.array).toBe(indexArray);
+    expect(lines.geometry.getAttribute('position').array).toBe(positionArray);
+    expect(lines.material.uniforms.uLowColor?.value).toBe(lowColor);
+    expect(lines.material.uniforms.uHighColor?.value).toBe(highColor);
+    expect(lines.material.uniforms.uRouteProgress?.value).toBe(1);
+    resources.dispose();
+  });
+
+  it('writes deterministic chapter blends into stable color allocations', () => {
+    const target = createMutableChapterPalette('deep-night');
+    const colorReferences = [
+      target.sky,
+      target.fog,
+      target.terrainLow,
+      target.terrainHigh,
+      target.sun,
+      target.haze,
+    ];
+
+    expect(Object.keys(CHAPTER_PALETTES)).toEqual([
+      'deep-night',
+      'systems',
+      'infrastructure',
+      'builds',
+      'pre-dawn',
+      'destination',
+    ] satisfies EnvironmentChapter[]);
+    expect(writeChapterPalette(target, 'deep-night', 'destination', 0.5)).toBe(target);
+    const first = paletteSnapshot(target);
+    expect(writeChapterPalette(target, 'deep-night', 'destination', 0.5)).toBe(target);
+    expect(paletteSnapshot(target)).toEqual(first);
+    expect([
+      target.sky,
+      target.fog,
+      target.terrainLow,
+      target.terrainHigh,
+      target.sun,
+      target.haze,
+    ]).toEqual(colorReferences);
+    expect(target.warmth).toBeGreaterThan(CHAPTER_PALETTES['deep-night'].warmth);
+    expect(target.warmth).toBeLessThan(CHAPTER_PALETTES.destination.warmth);
+  });
+});
+
+function paletteSnapshot(palette: ReturnType<typeof createMutableChapterPalette>) {
+  return {
+    sky: palette.sky.getHex(),
+    fog: palette.fog.getHex(),
+    terrainLow: palette.terrainLow.getHex(),
+    terrainHigh: palette.terrainHigh.getHex(),
+    sun: palette.sun.getHex(),
+    haze: palette.haze.getHex(),
+    warmth: palette.warmth,
+    terrainEnergy: palette.terrainEnergy,
+    starVisibility: palette.starVisibility,
+    streakEnergy: palette.streakEnergy,
+  };
+}
+
+interface ShaderRenderable {
+  geometry: {
+    index: { array: ArrayLike<number> } | null;
+    boundingBox: { min: { x: number }; max: { x: number } } | null;
+    computeBoundingBox(): void;
+    getAttribute(name: string): { count: number; array: ArrayLike<number> };
+  };
+  material: {
+    uniforms: Record<string, { value: unknown }>;
+    vertexShader: string;
+    fragmentShader: string;
+  };
+}