如何在 Unity 中获得 OnTriggerEnter 角度？ C＃

Question

Im making a basketball game where I put collider to The hoop and checked "is trigger" so I can detect when the ball passes throught it. But i want this to happen only when ball passes through it from above, not beneath. How can I solve it ?

Answer 1

The simple solution to this problem is to use Vector3.Dot . This method works in such a way that when the two angles are equal, it returns the value of 1, when it is perpendicular, it returns the value of 0, and when it is opposite, it shows the value of -1, the rest is between these numbers. Now you only need to measure the dot axis of the ball velocity with the downward direction. Numbers greater than zero definitely indicate acceleration from top to bottom.

public class Ball : MonoBehaviour
{
    private void OnTriggerEnter(Collider Basket)
    {
        if (Vector3.Dot(GetComponent<Rigidbody>().velocity, Vector3.down) > 0)
        {
            Debug.Log("Goal");
        }
    }
}