IWSDK Physics System Guide

This skill provides the complete reference and workflow for implementing Havok-powered physics simulation in IWSDK applications. Physics is built on three ECS components (PhysicsBody, PhysicsShape, PhysicsManipulation) orchestrated by the PhysicsSystem.

Enabling Physics

Enable physics in World.create with the physics feature flag:

import { World, SessionMode } from '@iwsdk/core';

const world = await World.create(container, {
  xr: { sessionMode: SessionMode.ImmersiveVR },
  features: {
    physics: true,
    grabbing: true, // Required if physics objects should be grabbable
    locomotion: true, // Requires collision geometry in the scene
  },
  level: './glxf/Composition.glxf',
});

Setting physics: true automatically registers PhysicsBody, PhysicsShape, PhysicsManipulation components and the PhysicsSystem at priority -2.

Only enable physics when needed. If no objects require dynamic simulation, omit it to avoid overhead.

PhysicsBody Component Reference

Defines the motion behavior of a physics entity. Import from @iwsdk/core.

import { PhysicsBody, PhysicsState } from '@iwsdk/core';

entity.addComponent(PhysicsBody, {
  state: PhysicsState.Dynamic,
  linearDamping: 0.0,
  angularDamping: 0.0,
  gravityFactor: 1.0,
  centerOfMass: [Infinity, Infinity, Infinity], // Infinity = auto-compute from shape
});

Properties:

Read-only properties (updated each frame by PhysicsSystem):

PhysicsState Enum

PhysicsState.Static; // Immovable (walls, floors). Zero simulation cost.
PhysicsState.Dynamic; // Fully simulated. Responds to forces, gravity, collisions.
PhysicsState.Kinematic; // Programmatically moved. Pushes dynamic bodies but is not affected by them.

When to use each:

• Static -- Environment geometry (walls, floors, tables). Objects that never move but block dynamic bodies.
• Dynamic -- Objects that respond to physics (balls, crates, interactive props). Default for most gameplay objects.
• Kinematic -- Moving platforms that won't be pushed by other physics bodies.

PhysicsShape Component Reference

Defines the collision geometry and material properties. Both PhysicsShape and PhysicsBody are required for physics simulation.

import { PhysicsShape, PhysicsShapeType } from '@iwsdk/core';

entity.addComponent(PhysicsShape, {
  shape: PhysicsShapeType.Auto,
  dimensions: [0, 0, 0],
  density: 1.0,
  restitution: 0.0,
  friction: 0.5,
});

Properties:

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