Creating a Physics Entity

In order for an entity to behave using realistic physics, you'll need to implement EntityPhysicsElement into your existing entity class. Here's an example similar to the example mod:
public class MyCustomPhysicsEntity extends Entity implements EntityPhysicsElement {
private final EntityRigidBody rigidBody = new EntityRigidBody(this);
public MyCustomPhysicsEntity (EntityType<?> entityType, World world) {
super(entityType, world);
this.rigidBody.setMass(10); // 10 kg
}
@Override
public ElementRigidBody getRigidBody() {
return this.rigidBody;
}
}