ECS Query Patterns

What problem does it solve?

This Skill helps you find and process the right entities in an ECS without wasting frame time on allocations, repeated query setup, or inefficient per-entity checks.

Core Features & Use Cases

• Query Filtering: Build precise entity matches with WithAll, WithAny, WithNone, and stricter archetype rules.
• Hot-Path Iteration: Use struct-based handlers and ref iteration to keep gameplay systems allocation-free.
• Reusable Queries: Cache QueryDescription instances for combat, movement, AI, and other per-frame systems.
• Bulk and Relationship Operations: Count, collect, add, remove, and update components across matching entities, including parent-child style relationships.
• Use Case: A Godot 4.x action game can use this Skill to update all enemies, apply damage only to valid targets, and keep simulation code deterministic and fast.

Quick Start

Use this skill to design an efficient Arch ECS query for the entities and components you need, then cache it and iterate with a zero-allocation handler.