public class TurretAim : ComponentSystem
{
    protected override void OnUpdate()
    { 
        EntityManager entityManager = World.DefaultGameObjectInjectionWorld.EntityManager;
        Entities.WithAll<HasTarget>().ForEach((Entity entity, ref Translation turretPos, ref Rotation turretRot, ref Angle angle, ref HasTarget target)=>{
                if(target.target != Entity.Null && EntityManager.Exists(target.target)){
                    Translation enemyPos = entityManager.GetComponentData<Translation>(target.target);

                    float3 targetVec = enemyPos.Value - turretPos.Value;

                    float len = targetVec.x*targetVec.x + targetVec.y*targetVec.y + targetVec.z*targetVec.z;
                    len = Mathf.Sqrt(len);

                    float a = targetVec.z / len;

                    a = Mathf.Acos(a);

                    float rad = angle.angle * Mathf.Deg2Rad;

                    if(targetVec.x <  0) a = -a;

                    float speedInDeg = 90.0f;
                    float maxDelta = Mathf.Deg2Rad * speedInDeg * Time.DeltaTime;

                    float newRot = Mathf.MoveTowards(rad, a, maxDelta);
                    angle.angle = newRot * Mathf.Rad2Deg;
                    turretRot.Value = quaternion.EulerXYZ(0, newRot, 0);
                }
                else{
                    PostUpdateCommands.RemoveComponent(entity, typeof(HasTarget));
                }
            

        });
    }
}