How can i Move the 3d Object in Terrain in Touch Input

Scene & World Building Terrain
1

Hi all

Have a Nice day. In my project I have a 3d Object .for eg sphere. When i touch the object the object should

move. I have found the code for that. I have enclose with the code.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class DragDropScript : MonoBehaviour
{
    //Initialize Variables
    GameObject getTarget;
    bool isMouseDragging;
    Vector3 offsetValue;
    Vector3 positionOfScreen;
    // Use this for initialization
    void Start()
    {
    }
    void Update()
    {
        //Mouse Button Press Down
        if (Input.GetMouseButtonDown(0))
        {
            RaycastHit hitInfo;
            getTarget = ReturnClickedObject(out hitInfo);
            if (getTarget != null)
            {
                isMouseDragging = true;
                //Converting world position to screen position.
                positionOfScreen = Camera.main.WorldToScreenPoint(getTarget.transform.position);
                offsetValue = getTarget.transform.position - Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, positionOfScreen.z));
            }
        }
        //Mouse Button Up
        if (Input.GetMouseButtonUp(0))
        {
            isMouseDragging = false;
        }
        //Is mouse Moving
        if (isMouseDragging)
        {
            //tracking mouse position.
            Vector3 currentScreenSpace = new Vector3(Input.mousePosition.x, Input.mousePosition.y, positionOfScreen.z);
            //converting screen position to world position with offset changes.
            Vector3 currentPosition = Camera.main.ScreenToWorldPoint(currentScreenSpace) + offsetValue;
            //It will update target gameobject's current postion.
            getTarget.transform.position = currentPosition;
        }
    }
    //Method to Return Clicked Object
    GameObject ReturnClickedObject(out RaycastHit hit)
    {
        GameObject target = null;
        Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
        if (Physics.Raycast(ray.origin, ray.direction * 10, out hit))
        {
            target = hit.collider.gameObject;
        }
        return target;
    }
}

But the Object moves on where i touch the finger.But it should go on the terrain . Like in the Edit View

after selecting the object if
we press ctrl+shift. the object is moving on the terrain . Like similar functionality
is needed for me.In touch.

How can i do it…

Any help … Appreciated…
Thanks in Advance…

2

One way to do this could be to ray cast at the current mouse position to the terrain and place your object based on the hit point.

3

You could try something like this:

using UnityEngine;
using UnityEngine.EventSystems;

public class Test1 : MonoBehaviour, IDragHandler
{
    RaycastHit[] hits = new RaycastHit[4];
    public void OnDrag(PointerEventData eventData)
    {
        Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
        int cnt = Physics.RaycastNonAlloc(ray, hits);
        int idx = -1;
        for(int i = 0; i < cnt; ++i)
        {
            if (hits[i].collider.CompareTag("Finish"))
            {
                idx = i;
                break;
            }
        }
        if(idx >= 0)
        {
            Transform trans = transform;
            RaycastHit hit = hits[idx];
            trans.up = hit.normal;
            trans.position = hit.point + trans.up * trans.localScale.y * .5f;
        }
    }
}

That will put the object on the ground. Change the ‘Finish’ tag to something else, or remove that check. If you remove that check, then be sure to skip the actual game object being dragged from the results.

This code also rotates the game object so it’s flat on the ground… Not sure if that was wanted. It also limits the number of raycasthits to 4.

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