Needs the com.meta.spatial.physics.PhysicsFeature to be enabled to work. Consider using the com.meta.spatial.physics.Physics component before implementing a custom physics system.

Example of a Custom Physics System, which creates a Physics box with initial linear velocity specified by the CustomPhysics component.

Component:

<?xml version="1.0" ?>
<ComponentSchema packageName="com.meta.aether.apps.experiments.physics">
 <Component name="CustomPhysics">
   <Vector3Attribute
     name="initialLinearVelocity"
     defaultValue="0.0f, 0.0f, 0.0f"
   />
 </Component>
</ComponentSchema>

System:

class CustomPhysicsSystem() : SystemBase() {
private val physicsObjects_ = HashMap<Entity, ScenePhysicsObject>()

override fun execute() {
  val q = Query.where { changed(CustomPhysics.id) and has(Transform.id) }
  for (ent in q.eval()) {
    if (physicsObjects_.containsKey(ent)) {
      continue
    }
    val physics = ScenePhysicsObject.createBox(getScene(), ent, 0.25f, 0.25f, 0.25f, 0.5f)
    physicsObjects_.put(ent, physics)
    physics.setPose(ent.getComponent<Transform>().transform)
    physics.setLinearVelocity(ent.getComponent<CustomPhysics>().initialLinearVelocity)
    Log.i("Physics", "Created physics object for entity $ent $physics")
  }
}

override fun delete(entity: Entity) {
  if (physicsObjects_.containsKey(entity)) {
    physicsObjects_[entity]?.destroy()
    physicsObjects_.remove(entity)
  }
}

Types

Name	Summary
Companion	object Companion

Properties

Name	Summary
entity	val entity: Entity?
handle	var handle: Long Native handle to the physics object.

Functions

Name	Summary
applyForce	fun applyForce(force: Vector3) Applies a force to this physics object
applyForceAtRelativePosition	fun applyForceAtRelativePosition(force: Vector3, relativePos: Vector3) Applies a force to this physics object at a specified position relative to its center.
applyTorque	fun applyTorque(torqueX: Float, torqueY: Float, torqueZ: Float) Applies a torque (rotational force) to this physics object.
destroy	fun destroy()
getPose	fun getPose(): Pose Gets the current position and rotation of this physics object.
setAngularVelocity	fun setAngularVelocity(angularVelocity: Vector3) Sets the angular velocity of this physics object.
setFriction	fun setFriction(friction: Float, rolling: Float = friction, spinning: Float) Sets the friction properties of this physics object.
setLinearVelocity	fun setLinearVelocity(velocity: Vector3) Sets the linear velocity of this physics object.
setPose	fun setPose(pose: Pose) Sets the position and rotation of this physics object.
setRestitution	fun setRestitution(restitution: Float) Sets the restitution (bounciness) of this physics object.

Companion

object Companion

Functions

Name	Summary
createBox	fun createBox(scene: Scene, entity: Entity?, width: Float, height: Float, depth: Float, mass: Float): ScenePhysicsObject Creates a box-shaped physics object.
createGLTF	fun createGLTF(scene: Scene, entity: Entity?, filename: String, mass: Float): ScenePhysicsObject Creates a physics object from a GLTF model file.
createSphere	fun createSphere(scene: Scene, entity: Entity?, radius: Float, mass: Float): ScenePhysicsObject Creates a sphere-shaped physics object.
setCallbackEntities	fun setCallbackEntities(scene: Long, entities: LongArray) Sets the entities that will receive physics callbacks.