// Update is called every frame.
Update is called every frame.
// Update is called every frame .
func (t *PhysicsSpheres) Update(a *app.App, deltaTime time.Duration) {
	t.sim.Step(float32(deltaTime.Seconds()))
	t.anim.Update(time.Now())
}
func ( t * PhysicsSpheres ) Update ( a * app . App , deltaTime time . Duration ) { t . sim . Step ( float32 ( deltaTime . Seconds ( ) ) ) t . anim . Update ( time . Now ( ) ) }
Update is called every frame.
Update is called every frame .