---
title: "Components"
description: "Last verified: 2026-06-17"
engineVersion: v1.0.234
date: 2026-09-28
license: "(c) Gessa, proprietary. Cite with attribution to https://gessa.ai/docs/. Terms: https://gessa.ai/terms/."
canonical: https://gessa.ai/docs/creator/components/README/
---
# Components

Last verified: 2026-06-17

Components are the typed building blocks attached to entities. The engine has 26 built-in ECS components. Most can be added from the Inspector or component palette; runtime-only components are used through their governed engine operations.

Raw field defaults live in `docs/spec/COMPONENT_TYPE_DEFINITIONS.md`. The developer contract lives in `docs/spec/ECS_CANON.md`.

## Catalog

| Component | Category | Creator surface | Use |
|---|---|---|---|
| TransformComponent | Spatial | Default | Position, rotation, and scale. |
| RenderableComponent | Rendering | Default | Mesh or primitive rendering. |
| SpatialCaptureComponent | Rendering | Advanced | Placed imported spatial capture or splat asset. |
| MaterialInstanceOverrideComponent | Rendering | Default | Per-entity material tint/opacity/emissive changes. |
| AnimationStateComponent | Rendering | Default | Mesh animation clip playback state. |
| HairComponent | Rendering | Advanced | Groom binding and render/simulation intent. |
| ColliderComponent | Physics | Default | Collision volume, trigger, or query target. |
| RigidBodyComponent | Physics | Default | Dynamic, kinematic, or static physics body. |
| ForceComponent | Physics | Hidden runtime component | Pending forces, impulses, and torques. |
| VelocityComponent | Physics | Default | Current velocity state and damping. |
| NetworkProfileComponent | Runtime | Advanced | Replication and authority profile. |
| CharacterMovementComponent | Physics | Default | Kinematic character movement configuration. |
| TimerComponent | Runtime | Default | Repeating or one-shot runtime tick event source. |
| CameraComponent | Rendering | Default | Viewpoint and camera follow/look-at behavior. |
| InputProfileComponent | Input | Composite Input section | Owns input actions, policy, prediction, and action-scoped bindings. |
| ScriptComponent | Scripting | Default | Attaches TypeScript behavior. |
| LightComponent | Rendering | Default | Scene lighting. |
| ReflectionProbeComponent | Rendering | Advanced | Local reflection capture. |
| LocalEnvironmentVolumeComponent | Rendering | Advanced | Bounded environment and presentation overrides. |
| TerrainComponent | Rendering | Advanced | Terrain surface rendering. |
| WaterComponent | Rendering | Advanced | Water surface rendering. |
| NavAgentComponent | Physics | Advanced | Server-owned path-following agent intent. |
| DecalComponent | Rendering | Advanced | Projected surface detail. |
| ParticleEmitterComponent | Rendering | Default | Particle effects. |
| TextRenderableComponent | Rendering | Advanced | World-space text. |
| AudioEmitterComponent | Audio | Default | Positional or global audio playback. |

## Guides

- [Spatial and Rendering](spatial-and-rendering.md)
- [Renderer Visual Profiles](renderer-visual-profiles.md)
- [Physics](physics.md)
- [Input, Runtime, and Scripting](input-runtime-and-scripting.md)
- [Audio](audio.md)

## Dependency Behavior

When you add a component that requires placement, the engine auto-adds Transform if it is missing. Force auto-adds RigidBody and Transform because a force has no effect without a body. Removing a required component is blocked until dependent components are removed.

## AI Access

AI tools can inspect component schemas, list components on entities, add components, edit fields, remove components, and set prefab overrides through approval-gated project graph tools. Entity hierarchy is authored through the entity record's parent and sibling fields, not through an ECS component.