Move to touch position

Archived Forums Questions & Answers
1

I wrote this script to make the object move to the position, where the player touched. It gets the finger position correctly, but does not change it to world point value. If I were to use the original value, the object would move far away.

using UnityEngine;
using System.Collections;

public class Player : MonoBehaviour {
	public Vector3 realPos;
	public Vector3 tempPos;
	
	// Update is called once per frame
	void Update () {
		if(transform.position != realPos) {
			transform.position = Vector3.Lerp (transform.position, realPos, 0.3f);
		}

		if(Input.touchCount > 0 && Input.GetTouch(0).phase == TouchPhase.Began) {
			Vector3 fingerPos = Input.GetTouch(0).position;

			tempPos = fingerPos;
			tempPos.z = 0;
			realPos = Camera.main.ScreenToWorldPoint(tempPos);
			realPos.z = 0;
			Debug.Log (tempPos);
		}
	}
}
2

There is a likely problem here. Your code:

        tempPos = fingerPos;
        tempPos.z = 0;
        realPos = Camera.main.ScreenToWorldPoint(tempPos);
        realPos.z = 0;
        Debug.Log (tempPos);

…will only work for an Orthographic camera. And if want your object to have a ‘z’ value of 0.0. For a perspective camera, you need to assign the ‘z’ of tempPos the distance in front of the camera before you call ScreenToWorldPoint(). So if the camera was at -10 and you wanted to find the position at ‘z = 0’ (10 units in front of the camera):

tempPos.z = 10.0;
realPos = Camera.main.ScreenToWorldPoint(tempPos);

Note for your movement code, you should be using deltaTime.

 transform.position = Vector3.Lerp (transform.position, realPos, Time.deltaTime * 6.0);