Callbacks & Events

Scene Update

Because Physijs runs on a different thread than your main application, there is no guarantee that it will be able to iterate the scene every time you call scene.simulate. Because of this, you may attach an event listener to the scene that is triggered whenever the physics simulation has run.

var scene = new Physijs.scene;
scene.addEventListener( 'update', function() {
    // the scene's physics have finished updating
});

Collisions

To be notified when an object experiences a collision with another object, you can attach a collision event listener to individual objects.

var mesh = new Physijs.BoxMesh( geometry, material );
mesh.addEventListener( 'collision', function( other_object, linear_velocity, angular_velocity ) {
    // `this` is the mesh with the event listener
    // other_object is the object `this` collided with
    // linear_velocity and angular_velocity are Vector3 objects which represent the velocity of the collision
});

Adding an object

If your scene is complex or has a lot of objects, the physics simulation can slow down to the point where adding new objects can become a lot of work for the application. To help alleviate some of the pain this may cause, objects have a ready event which is triggered after the object has been added to the physics simulation. This can be seen in many of the examples in order to avoid flooding the scene with new objects as the simulation slows down.

var readyHandler = function() {
    // object has been added to the scene
};
var mesh = new Physijs.SphereMesh( geometry, material );
mesh.addEventListener( 'ready', readyHandler );
scene.add( mesh );