Static

Static bodies represent fixed geometry: level collision, invisible blockers, and stationary trigger volumes. They never integrate velocity or respond to forces.

Add StaticBodyAuthoring in a subscene. Like kinematic bodies, statics support rigid and trigger modes via IsTrigger.

Rigid vs trigger

  Rigid (IsTrigger = false) Trigger (IsTrigger = true)
Physical effect Pushes dynamic bodies None — overlap only
Spatial map Added to the static map once after creation (TimeElapsed = -1) Same one-time placement
Who initiates overlap tests Dynamic and kinematic bodies during pair collection Dynamic and kinematic bodies when they query the static map
Intersection targets Dynamics (and kinematics in broad phase) Dynamic and kinematic objects only — static bodies do not run pair collection, so static–static trigger pairs are not detected
Typical use Walls, floors (when not using a surface), pillars Stationary pickup zones, room bounds

Static triggers do not detect other static or trigger-only volumes on their own. A kinematic trigger that updates on an interval can overlap a static trigger when the kinematic body runs pair collection against the static map.

Shape options

Shape Authoring enum
Sphere ColliderType.Sphere
Capsule ColliderType.Capsule

Use ColliderScale and ColliderLocalPosition like other body types.

Scene view

When the GameObject is selected, the Scene view draws a wireframe sphere or capsule using the same rules as kinematic bodies: yellow for rigid colliders, blue for triggers. Size and offset reflect ColliderScale, ColliderLocalPosition, and transform scale.

What does not affect static bodies

  • No gravity, friction integration, or velocity.
  • PhysicsVelocityAuthoring logs a warning and is ignored on static authorings.
  • Static entities are not tested against surfaces in the built-in surface collision pass (that job skips body.IsStatic).

For ground and large bounds, prefer SurfaceBodyAuthoring when you need every dynamic body checked every substep without spatial-map cell limits.

Authoring fields

Field Default Role
Collider Sphere Sphere or capsule
ColliderScale 1 Collider size
ColliderLocalPosition (0,0,0) Local offset
Bounciness 0 Material when pushing dynamics
Friction 0.5 Material when pushing dynamics
Hardness 1 Push-out weight vs dynamics
IsTrigger false Rigid vs trigger mode

Map update behavior

On bake, static bodies receive PhysicsBodyUpdateComponent with TimeElapsed = -1. The collision map system treats that as “insert once”: the body’s AABB is written to StaticMap the first time it qualifies for update, then skipped on later substeps unless a kinematic/dynamic neighbor pulls it into pair tests from their side.

Dynamic and kinematic bodies move through the map each substep (or on trigger interval); statics stay in the cells where they were first placed.

When to use static vs surface

Use static rigid when… Use surface when…
Localized colliders inside the spatial map (posts, rocks, door frames) A single large ground plane or world bound
You need capsule or sphere push-out against dynamics in specific cells You need guaranteed dynamic-vs-ground tests every substep outside LOD pair budgets

Runtime creation

Use StaticBodyBuilder with .AsRigidBody(...) or .AsTrigger() for runtime spawning.

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