Issue with raycast, hit.collider.tag works sometimes

Questions & Answers
1

Desired Result:
I want to make it so that when I mouse click in my camera, a turret will spawn. But if a turret is in the way, do not spawn a turret.

The issue:
My code appears to work sometimes. Debug log will output that I can’t put a turret, other times it will spawn a turret over a turret when it shouldn’t.

Code in question:

#pragma strict

private var cam_speed : float = 0.008;
var theTurret : GameObject;

private var isIOSDevice : boolean = false;
var clickDetected : boolean;
var clickDetected2 : boolean;
var clickUnDetected2 : boolean;
var touchPosition : Vector3;
var dragTurretTarget : GameObject = null;
var dragTurret : boolean = false;

function Awake () 
{
	if (Application.platform == RuntimePlatform.IPhonePlayer)
	{ 
        isIOSDevice = true;
    } 
    else
    {
        isIOSDevice = false;
	}
}

function Update ()
{
	//Speed of Cam Scrolling
	transform.position.x += cam_speed;
							
	//Detect click and calculate touch position
	if (isIOSDevice) 
	{
		//Variables for spawning turret based on a tap
        clickDetected = (Input.touchCount > 0 && Input.GetTouch(0).phase == TouchPhase.Began);
        touchPosition = Input.GetTouch(0).position;
        
        //Variables for dragging turret with finger
        clickDetected2 = (Input.touchCount > 0 && Input.GetTouch(0).phase == TouchPhase.Began);
        //touchPosition2 = Input.GetTouch(0).position;
    } 
    else 
    {
    	//Variables for spawning turret based on a mouseclick
        clickDetected = (Input.GetMouseButtonDown(0));
        touchPosition = Input.mousePosition;
        
        //Variables for dragging turret with mousedrag
        clickDetected2 = (Input.GetMouseButton(1));
        clickUnDetected2 = (Input.GetMouseButtonUp(1));
        //touchPosition2 = Input.mousePosition;
    }
 
    //Detect click/tap to spawn turret
    if (clickDetected) 
    {
    	buildTurret();  
    }
    
    //Detect drag to drag turret
    if (clickDetected2)
    {
    	checkDragTurret();
    }
    if (clickUnDetected2)
    {
    	dragTurret = false;
    }   
}

function buildTurret()
{
		//var mousePos = Input.mousePosition;
 		
		var ray : Ray = GameObject.FindWithTag("MainCamera").camera.main.ScreenPointToRay (touchPosition);

  		var hit : RaycastHit;

    	if (Physics.Raycast (ray, hit, Mathf.Infinity)) 
    	{
    		if (hit.collider.tag == "TurretCollision")
    		{
    			Debug.Log("Can't deploy, another turret is there.");
    		}
    		else
    		{
    			var newTurret = Instantiate(theTurret, hit.point, Quaternion.identity);
        		newTurret.transform.position.y = 0.5;
    		}
    	}
}

function checkDragTurret()
{
		var dragMousePos = Input.mousePosition;
 		
		var dragRay : Ray = GameObject.FindWithTag("MainCamera").camera.main.ScreenPointToRay (touchPosition);

  		var dragHit : RaycastHit;
  		
  		if (Physics.Raycast (dragRay, dragHit, Mathf.Infinity)) 
    	{
    		if (dragHit.collider.tag == "TurretCollision")
    		{
    			
    			dragTurretTarget = dragHit.transform.parent.gameObject;
    			dragTurret = true; 			
    		}
    		if (dragTurret == true)
    			{
    				dragTurretTarget.transform.position = dragHit.point;
    				dragTurretTarget.transform.position.y = 0.5;
    			}
    	}
}
2

I see that u do not use raycasthit in ur update function this causes unity not to be able to calculate where on each frame ur raycast is hit.for proper
raycast detection change the design of ur code then it should work

Also change this

if (Physics.Raycast (dragRay, dragHit, Mathf.Infinity)) To

if (Physics.Raycast (dragRay,out dragHit, Mathf.Infinity))