Physics
Physics engines are third party external programs that can be plugged into Babylon.js. They, depending on their features, emulate "real-life" interactions between objects, which can be meshes, solid particles from the solid particle system or some cameras. One feature of a Physics Engine is the addition of gravity to a scene.
There are 2 physics architecture in Babylon.js.
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a Version 2 (V2 for short) with support for modern Physics Engines.
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Version 1 (V1 for short), which is a pre-6.0 Legacy API.
⚠️ The documentation for V1 has been moved to the Legacy section.
We strongly recommend using V2 over V1. A migration guide is here.
Physics V2
There are plugins for 1 physics engine:
- Havok - a powerful engine used in AAA games.
All need to be enabled before use.
This architecture allows finer grain control on your physics scene by making the difference between collision shapes and physical body. A typical use case is to have only one collision shape used by numerous bodies. This allows a lower memory footprint and more efficient memory addressing. A special effort has been put into better performance for a huge number of bodies. This is also the case for the collision callback mechanism.
A broad overview of the Physics V2 advancements is available on this Medium article.
Physics V1
There are plugins for 3 physics engines:
- Cannon.js - a wonderful physics engine written entirely in JavaScript.
- Oimo.js - a JS port of the lightweight Oimo physics engine.
- Ammo.js - a JS port of the bullet physics engine.
All need to be enabled before use.
Interactions between objects are achieved by imposters, simple objects that are attached to any complex objects with a scene. The imposter can be assigned physical attributes such as mass, friction, a coefficient of restitution, impulse, and linear and angular.
Two imposters can be connected using joints such as a hinge or ball and socket.
Ammo also allows the creation of soft bodies.
Coming next
Using A Physics Engine
Learn how to use one of the available physics engines in Babylon.js.

Physics V2 core concepts
All the concepts and objects designed for Physics V2 plugins

Physics V2 Shapes
Describing Shapes

Forces
Learn all about applying physical forces in Babylon.js.

Physics compounds
How to use compounds to model complex objects with simple primitives

Aggregates
How to use Physics Aggregate for fast and easy physics scene creation.

Collisions
How to access Collision Events

Constraints
Learn all about using Constraints with Babylon.js.

Raycast
How to use Physics for fast raycasting ?

Migrate from Physics V1
A guide on best practices to port a Physics V1 scene to V2

Performance Tips
A guide on best practices to achieve maximum performance with the Physics V2 API

Using Havok and the Havok Plugin
Learn how to use the havok plugin offered by Babylon.js
