How to detect a touch on Box Collider 2d in Unity 4.3

Archived Forums Questions & Answers
1

I am familiar with the 3D way of doing this

Ray ray = Camera.mainCamera.ScreenPointToRay(Input.GetTouch (0).position);
if (Physics.Raycast(ray, out hit))

But when I have a Box Collider 2D , the Ray doesn’t seem to hit, I tried using the Physics2D.Raycast but cannot get it also does not hit because its 2D ?

Thanks for any hints

3 Answers

3
2

Finally I managed to find the answer , in case somebody else who is not new to unity needs this the answer is

void Update()
{
    if (Input.touchCount == 1)
    {
        Vector3 wp = Camera.main.ScreenToWorldPoint(Input.GetTouch(0).position);
        Vector2 touchPos = new Vector2(wp.x, wp.y);
        if (collider2D == Physics2D.OverlapPoint(touchPos))
        {
            //your code

        }
    }
}

Thanks for sharing. I was using the same method in 3D and got stuck when I tried with 2D.

 –

How do you access that colliding object? Like if I wish to change its color or destroy it?

 –

This script is ideally attached to the object so you will have direct access, but for other collisions you have to use OnCollisionEnter2D , see this http://docs.unity3d.com/Documentation/ScriptReference/MonoBehaviour.OnCollisionEnter.html

 –

I'm trying to run a foreach loop through touches in a separate script. I need to access the objects that I tap and change color. Could you help me out?

 –

Post your question to the community with details on what are your trying to do , I am very new to unity myself

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3

Hi thank you for the code, i have a question for you, with this script if i continue to press the screen the code is “repeating”, the is a way to stop this, i mean i want to repeat my code but i want to tap again, i want to avoid that whit pressure the code is repeating…

4

In case anyone is wondering what this should be for Unity 2019.3, 1st make sure the Game Object has a 2D Collider component, then add the following script:

void Update()
{
    if (Input.touchCount > 0)
    {
        Vector3 wp = Camera.main.ScreenToWorldPoint(Input.GetTouch(0).position);
        if (GetComponent<Collider2D>().OverlapPoint(wp))
        {
            //your code
            Debug.Log("Hello");
        }
    }
}