rpg-mcp

import { describe, it, expect } from 'vitest'; import { generateHeightmap } from '../../src/engine/worldgen/heightmap'; /** * Terrain Quality Gates * * These tests define quality benchmarks inspired by Azgaar's Fantasy Map Generator. * They serve as acceptance criteria for terrain generation algorithms. * * Reference: reference/AZGAAR_SNAPSHOT.md */ describe('Terrain Quality Gates', () => { describe('Terrain Continuity', () => { it('should not have abrupt elevation jumps between neighbors', () => { // Test seed for deterministic terrain const seed = 'terrain-continuity-001'; // Generate small test heightmap (10x10 grid) const heightmap = generateHeightmap(seed, 10, 10); // Check all adjacent cells for maximum elevation delta const MAX_ELEVATION_DELTA = 30; // Allow up to 30 units difference (0-100 scale) // Helper to access 1D array as 2D const get = (y: number, x: number) => heightmap[y * 10 + x]; for (let y = 0; y < 10; y++) { for (let x = 0; x < 10; x++) { const current = get(y, x); // Check right neighbor if (x < 9) { const right = get(y, x + 1); const delta = Math.abs(current - right); expect(delta).toBeLessThanOrEqual(MAX_ELEVATION_DELTA); } // Check bottom neighbor if (y < 9) { const bottom = get(y + 1, x); const delta = Math.abs(current - bottom); expect(delta).toBeLessThanOrEqual(MAX_ELEVATION_DELTA); } // Check diagonal neighbors (for smoothness) if (x < 9 && y < 9) { const diagonal = get(y + 1, x + 1); const delta = Math.abs(current - diagonal); expect(delta).toBeLessThanOrEqual(MAX_ELEVATION_DELTA * 1.4); // Allow slightly more for diagonals } } } }); it('should produce smooth gradients in non-mountainous regions', () => { const seed = 'smooth-terrain-001'; const width = 20; const height = 20; const heightmap = generateHeightmap(seed, width, height); const get = (y: number, x: number) => heightmap[y * width + x]; // Sample a central region (avoiding edges and extremes) for (let y = 5; y < 15; y++) { for (let x = 5; x < 15; x++) { const elevation = get(y, x); // Only test relatively flat areas (20-60 elevation) if (elevation >= 20 && elevation <= 60) { // Get 3x3 neighborhood const neighborhood = [ get(y - 1, x - 1), get(y - 1, x), get(y - 1, x + 1), get(y, x - 1), get(y, x), get(y, x + 1), get(y + 1, x - 1), get(y + 1, x), get(y + 1, x + 1), ]; // Calculate standard deviation const mean = neighborhood.reduce((sum, val) => sum + val, 0) / neighborhood.length; const variance = neighborhood.reduce((sum, val) => sum + Math.pow(val - mean, 2), 0) / neighborhood.length; const stdDev = Math.sqrt(variance); // In smooth regions, std dev should be relatively low expect(stdDev).toBeLessThan(15); } } } }); it('should maintain consistent land-to-sea ratio', () => { const seed = 'land-ratio-001'; const width = 50; const height = 50; const heightmap = generateHeightmap(seed, width, height); const get = (y: number, x: number) => heightmap[y * width + x]; const SEA_LEVEL = 20; // From Azgaar's MIN_LAND_HEIGHT constant let landCount = 0; let totalCount = 0; for (let y = 0; y < 50; y++) { for (let x = 0; x < 50; x++) { totalCount++; if (get(y, x) >= SEA_LEVEL) { landCount++; } } } const landRatio = landCount / totalCount; // Azgaar typically generates 20-40% land expect(landRatio).toBeGreaterThan(0.2); expect(landRatio).toBeLessThan(0.5); }); }); describe('Elevation Distribution', () => { it('should have realistic elevation distribution', () => { const seed = 'elevation-dist-001'; const width = 40; const height = 40; const heightmap = generateHeightmap(seed, width, height); const get = (y: number, x: number) => heightmap[y * width + x]; // Count cells in elevation bands const bands = { deepOcean: 0, // 0-10 shallowOcean: 0, // 10-20 lowland: 0, // 20-40 highland: 0, // 40-60 mountain: 0, // 60-80 highMountain: 0, // 80-100 }; for (let y = 0; y < 40; y++) { for (let x = 0; x < 40; x++) { const elevation = get(y, x); if (elevation < 10) bands.deepOcean++; else if (elevation < 20) bands.shallowOcean++; else if (elevation < 40) bands.lowland++; else if (elevation < 60) bands.highland++; else if (elevation < 80) bands.mountain++; else bands.highMountain++; } } const total = 40 * 40; // Most terrain should be ocean or lowland expect(bands.deepOcean + bands.shallowOcean + bands.lowland).toBeGreaterThan(total * 0.6); // High mountains should be rare expect(bands.highMountain).toBeLessThan(total * 0.1); // Should have some variety (not all one elevation) expect(Object.values(bands).filter((count) => count > 0).length).toBeGreaterThanOrEqual(4); }); it('should have valid elevation range (0-100)', () => { const seed = 'elevation-range-001'; const width = 30; const height = 30; const heightmap = generateHeightmap(seed, width, height); const get = (y: number, x: number) => heightmap[y * width + x]; for (let y = 0; y < 30; y++) { for (let x = 0; x < 30; x++) { const elevation = get(y, x); expect(elevation).toBeGreaterThanOrEqual(0); expect(elevation).toBeLessThanOrEqual(100); expect(Number.isInteger(elevation)).toBe(true); // Should be integer values } } }); }); describe('Determinism', () => { it('should produce identical heightmaps for the same seed', () => { const seed = 'determinism-001'; const width = 15; const height = 15; const heightmap1 = generateHeightmap(seed, width, height); const heightmap2 = generateHeightmap(seed, width, height); // Compare every cell for (let i = 0; i < width * height; i++) { expect(heightmap1[i]).toBe(heightmap2[i]); } }); it('should produce different heightmaps for different seeds', () => { const seed1 = 'seed-alpha'; const seed2 = 'seed-beta'; const width = 15; const height = 15; const heightmap1 = generateHeightmap(seed1, width, height); const heightmap2 = generateHeightmap(seed2, width, height); // Count differences let differences = 0; for (let i = 0; i < width * height; i++) { if (heightmap1[i] !== heightmap2[i]) { differences++; } } // Should be significantly different (at least 50% different) expect(differences).toBeGreaterThan((15 * 15) / 2); }); }); });