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name: terrain-integration description: Terrain interaction systems for Three.js building games. Use when implementing slope handling, foundation anchoring (Valheim pattern), terrain modification, auto-leveling, or pillar/support generation. Integrates with structural-physics for ground-based stability.

Terrain Integration

Foundation placement, slope handling, and terrain modification for building systems.

Quick Start

Copyimport { TerrainAnalyzer } from './scripts/terrain-analyzer.js';
import { FoundationPlacer } from './scripts/foundation-placer.js';

// Analyze terrain at build location
const analyzer = new TerrainAnalyzer(terrainMesh);
const slopeData = analyzer.analyzeSlope(position, { radius: 4 });
// slopeData: { angle: 15, normal: Vector3, canBuild: true }

// Place foundation with auto-leveling
const placer = new FoundationPlacer({ 
  mode: 'valheim', // or 'rust', 'ark'
  maxSlope: 30,
  autoLevel: true 
});
const result = placer.place(foundationPiece, position, analyzer);
// result: { valid: true, height: 2.3, pillarsNeeded: 2 }

Reference

See references/terrain-integration-advanced.md for:

• Slope analysis algorithms and thresholds
• Foundation anchoring patterns (Valheim ground contact rule)
• Auto-leveling strategies
• Terrain modification networking
• Pillar generation for uneven terrain

Scripts

• scripts/terrain-analyzer.js - Slope detection, buildability checks, terrain sampling
• scripts/foundation-placer.js - Foundation placement with Valheim/Rust/ARK modes
• scripts/terrain-modifier.js - Flatten, raise, lower terrain operations
• scripts/pillar-generator.js - Auto-generate support pillars for slopes

Foundation Modes

• Valheim: Ground contact = 100% stability, foundations must touch terrain
• Rust: Foundations snap to grid, terrain ignored after placement
• ARK: Flexible placement with auto-pillars, moderate slope tolerance

Integration

Works with structural-physics for stability calculations. Grounded foundations feed into the support graph as root nodes with maximum stability.

Copy// Integration example
const grounded = placer.place(foundation, pos, analyzer);
if (grounded.valid) {
  foundation.isGrounded = true;
  foundation.stability = 1.0; // Feed to structural-physics
  validator.addPiece(foundation);
}