Nevo Engine

Reference Scenes

Use these sample scenes as current ground truth:

Nevo-base/game/levels/physics.json
Nevo-base/game/levels/outside.json

physics.json is compact and useful for testing dynamic objects. outside.json shows larger imported world geometry, mesh colliders, capsule colliders, and post-processing.

Dynamic Mesh Body

From the physics.json monkey setup:

{
  "type": "Rigidbody",
  "data": {
    "type": "Dynamic",
    "mass": 1.0,
    "linearVelocity": [0.0, 0.0, 0.0],
    "drag": 0.0,
    "useGravity": true,
    "freezeRotation": false
  }
},
{
  "type": "MeshCollider",
  "data": {
    "convex": true,
    "friction": 0.5,
    "restitution": 0.0,
    "isTrigger": false
  }
}

For dynamic mesh bodies, use convex: true unless you know the backend supports the shape you need.

Static World Mesh

From outside.json road geometry:

{
  "type": "Rigidbody",
  "data": {
    "type": "Static",
    "mass": 1.0,
    "linearVelocity": [0.0, 0.0, 0.0],
    "drag": 0.0,
    "useGravity": true
  }
},
{
  "type": "MeshCollider",
  "data": {
    "convex": true,
    "friction": 0.5,
    "restitution": 0.0,
    "isTrigger": false
  }
}

Static bodies do not need mass or gravity to move, but current scene output may still include those fields.

Kinematic Floor with BoxCollider

From physics.json floor pattern:

{
  "type": "Rigidbody",
  "data": {
    "type": "Kinematic",
    "mass": 0.0,
    "useGravity": false,
    "freezeRotation": true
  }
},
{
  "type": "BoxCollider",
  "data": {
    "center": [0.0, 0.0, 0.0],
    "size": [8.35, 0.1, 12.0],
    "friction": 0.8,
    "restitution": 0.0,
    "isTrigger": false
  }
}

Use box colliders for simple floors, platforms, and blocking volumes.

Capsule Body

From the outside.json tire-like capsule setup:

{
  "type": "Rigidbody",
  "data": {
    "type": "Dynamic",
    "mass": 1.0,
    "linearVelocity": [0.0, 0.0, 0.0],
    "useGravity": true
  }
},
{
  "type": "CapsuleCollider",
  "data": {
    "center": [0.0, 0.0, 0.0],
    "radius": 0.34,
    "height": 0.68,
    "friction": 0.5,
    "restitution": 0.0,
    "isTrigger": false
  }
}

Capsules are the preferred primitive for upright characters.

Collider Material Fields

Field	Meaning
`friction`	Surface friction, minimum `0`.
`restitution`	Bounce, clamped `0..1`.
`isTrigger`	Query/overlap style body rather than a solid collider.

Debugging Physics Scenes

Confirm the entity has Transform, Rigidbody, and exactly one intended collider.
Confirm dynamic bodies have nonzero mass.
Confirm primitive collider dimensions are not zero.
Confirm imported mesh paths resolve and are rendered.
Use GetPhysicsSystem()->HasBody(entity) when debugging game-created entities.
For controller-style logic, use public physics APIs rather than writing dynamic Transform every frame.

Physics Scene Setup