| name | building-router |
| description | Router for 3D building game mechanics in Three.js. Use when creating survival games, sandbox builders, base builders, or any game with player-constructed structures. Routes to 9 specialized skills for performance, physics, multiplayer, terrain, decay, UX, platform support, and design reference. Start here for building mechanics projects. |
Building Mechanics Router
Routes to 9 specialized skills based on game requirements.
Routing Protocol
- Classify — Single/multiplayer + scale + core features
- Match — Apply signal matching rules below
- Combine — Most games need 3-5 skills together
- Load — Read matched SKILL.md files before implementation
Quick Route
Tier 1: Core Mechanics
| Need |
Skill |
Signals |
| Spatial queries, collision |
performance-at-scale |
slow, lag, optimize, spatial, collision, thousands |
| Stability, damage, collapse |
structural-physics |
stability, collapse, support, damage, Fortnite, Rust, Valheim |
| Network sync, prediction |
multiplayer-building |
network, multiplayer, sync, server, latency, authoritative |
Tier 2: Enhanced Features
| Need |
Skill |
Signals |
| Slopes, foundations, anchoring |
terrain-integration |
slope, terrain, foundation, ground, pillar, heightmap |
| Timer decay, Tool Cupboard |
decay-upkeep |
decay, upkeep, maintenance, tool cupboard, abandoned |
| Blueprints, undo/redo, preview |
builder-ux |
blueprint, prefab, undo, redo, ghost, preview, selection |
Tier 3: Platform & Reference
| Need |
Skill |
Signals |
| Touch, VR, accessibility |
platform-building |
mobile, touch, VR, hand tracking, colorblind |
| Design analysis, trade-offs |
case-studies-reference |
how does Fortnite/Rust do, compare games, trade-offs |
Signal Priority
When multiple signals present:
- Multiplayer explicit →
multiplayer-building required
- Scale indicator → >1000 pieces triggers
performance-at-scale
- Persistence → Long-running servers trigger
decay-upkeep
- Platform constraint → Mobile/VR triggers
platform-building
- Default →
structural-physics always relevant for building games
Common Combinations
Full Survival (Rust-style, 6 skills)
performance-at-scale → spatial indexing
structural-physics → stability + damage
multiplayer-building → networking
terrain-integration → foundations on slopes
decay-upkeep → Tool Cupboard + upkeep
builder-ux → blueprints + undo
Battle Royale Building (2 skills)
performance-at-scale → fast collision
multiplayer-building → low-latency sync
Single-Player Builder (3-4 skills)
structural-physics → stability + damage
terrain-integration → natural terrain
builder-ux → blueprints + undo
performance-at-scale → if >1000 pieces
Persistent Server (4 skills)
multiplayer-building → networking
structural-physics → stability
decay-upkeep → automatic cleanup
performance-at-scale → entity management
Decision Table
| Mode |
Scale |
Terrain |
Skills |
| Single |
<1K |
Grid |
physics + ux |
| Single |
<1K |
Natural |
physics + terrain + ux |
| Single |
>1K |
Any |
performance + physics + ux |
| Multi |
Fast |
Any |
performance + multiplayer |
| Multi |
Survival |
Any |
performance + physics + multiplayer + decay |
| Multi |
Persistent |
Any |
performance + physics + multiplayer + decay + ux |
Integration Order
When combining skills, wire in this sequence:
- Spatial index → Query foundation for all other systems
- Validator → Uses spatial for neighbor/support detection
- Damage → Uses spatial for cascade radius
- Network → Broadcasts all state changes
- Client prediction → Uses local spatial + validator
Fallback
- No scale stated → Ask: "How many pieces expected?"
- Unclear mode → Ask: "Single-player or multiplayer?"
- Generic "building game" → Start with
structural-physics + builder-ux
Reference
See references/integration-guide.md for complete wiring patterns and code examples.