Touch a Sprite

Hello,
I'm new with Unity (but I'm not new with coding), i came from Xcode and SpriteKit.
I have been building a 2D game with Unity, and i have a simple sprite (a jump icon) and a character. All i want is that if i touch the jump icon (the Sprite) something happen in the game. In C#, how can i say "If i touch that sprite with that name do something". When i was using SpriteKit i was simply write:

If(node.name == "name") {.do something } inside a touchesBegan method.

How can i do that in Unity?

Thanks.

 

You want to "touch" it with a player or as an input (touch screen) ? :?

 

If the sprite has a collider, you can use OnMouseDown:

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3.  
4. public class ExampleClass : MonoBehaviour
5. {
6.     void OnMouseDown()
7.     {
8.         Application.LoadLevel("SomeLevel");
9.     }
10. }

https://docs.unity3d.com/ScriptReference/MonoBehaviour.OnMouseDown.html

I believe this does work for touch, but not multi-touch.

 

Hi thanks,

Yes i want to touch it as an input touch (with finger).

i could find this code:

Code (CSharp):

1. for (var i = 0; i < Input.touchCount; ++i) {
2.             if (Input.GetTouch(i).phase == TouchPhase.Began) {
3.                 RaycastHit2D hitInfo = Physics2D.Raycast(Camera.main.ScreenToWorldPoint(Input.GetTouch(i).position), Vector2.zero);
4.                 // RaycastHit2D can be either true or null, but has an implicit conversion to bool, so we can use it like this
5.                 if(hitInfo)
6.                 {
7.                     // Here you can check hitInfo to see which collider has been hit, and act appropriately
8.                     Debug.Log( hitInfo.transform.gameObject.name );
9.  
10.  
11.                 }
12.             }
13.         }

It works but i've got a small problem: The jump button in the scene is child of the player, so when i touch the button it's like touching the player... How can i make it recognise the button even if it is a player's child?

 

Well, there's probably a couple of ways to handle that. You can do a RaycastAll, and get multiple results, then check if any of the results were your button.

Another option would be to define a LayerMask, and use that LayerMask to only check for objects on that Layer.

So you can create a "UI" layer perhaps, set your button to that layer, then do this:

Code (CSharp):

1. public LayerMask touchLayers; // set up in the inspector
2.  
3. public void function() {
4.     for(var i = 0; i < Input.touchCount; ++i) {
5.         if(Input.GetTouch(i).phase == TouchPhase.Began) {
6.             Vector3 position = Camera.main.ScreenToWorldPoint(Input.GetTouch(i).position);
7.             // pass in LayerMask
8.             RaycastHit2D hitInfo = Physics2D.Raycast(position, Vector2.zero, Mathf.Infinity, touchLayers);
9.             // RaycastHit2D can be either true or null, but has an implicit conversion to bool, so we can use it like this
10.             if(hitInfo) {
11.                 // Here you can check hitInfo to see which collider has been hit, and act appropriately
12.                 Debug.Log(hitInfo.transform.gameObject.name);
13.             }
14.         }
15.     }
16. }

Another way would be to use collider2D.OverlapPoint() to check that specific collider for the mouse position overlap.

 

Thanks,
Okay i did the layers and it works, but the problem is the same: The button is child of player, so in console appears "Player" and not the real name of the button. How can i fix that?

 

If the layers are set up correctly, you would never detect the "Player" gameObject. The "hitInfo" would have a reference to the child object only.