How to add a Minimum and Maximum to pinch zoom touch script

Questions & Answers
1

using UnityEngine;

public class PinchZoom : MonoBehaviour
{
public float perspectiveZoomSpeed = 0.5f; // The rate of change of the field of view in perspective mode.
public float orthoZoomSpeed = 0.5f; // The rate of change of the orthographic size in orthographic mode.

void Update()
{
	// If there are two touches on the device...
	if (Input.touchCount == 2)
	{
		// Store both touches.
		Touch touchZero = Input.GetTouch(0);
		Touch touchOne = Input.GetTouch(1);
		
		// Find the position in the previous frame of each touch.
		Vector2 touchZeroPrevPos = touchZero.position - touchZero.deltaPosition;
		Vector2 touchOnePrevPos = touchOne.position - touchOne.deltaPosition;
		
		// Find the magnitude of the vector (the distance) between the touches in each frame.
		float prevTouchDeltaMag = (touchZeroPrevPos - touchOnePrevPos).magnitude;
		float touchDeltaMag = (touchZero.position - touchOne.position).magnitude;
		
		// Find the difference in the distances between each frame.
		float deltaMagnitudeDiff = prevTouchDeltaMag - touchDeltaMag;
		
		// If the camera is orthographic...
		if (GetComponent<Camera>().orthographic)
		{
			// ... change the orthographic size based on the change in distance between the touches.
			GetComponent<Camera>().orthographicSize += deltaMagnitudeDiff * orthoZoomSpeed;
			
			// Make sure the orthographic size never drops below zero.
			GetComponent<Camera>().orthographicSize = Mathf.Max(GetComponent<Camera>().orthographicSize, 0.1f);
		}
		else
		{
			// Otherwise change the field of view based on the change in distance between the touches.
			GetComponent<Camera>().fieldOfView += deltaMagnitudeDiff * perspectiveZoomSpeed;
			
			// Clamp the field of view to make sure it's between 0 and 180.
			GetComponent<Camera>().fieldOfView = Mathf.Clamp(GetComponent<Camera>().fieldOfView, 0.1f, 179.9f);
		}
	}
}

}

2

Well this is super old, but I was just doing the same thing and found the solution to this issue using the same script:

public float maxZoom = 10f; //farthest you can get
public float minZoom = 2f; //closest you can get

 void Update()
 {
    //...  
         // If the camera is orthographic...
         if (GetComponent<Camera>().orthographic)
         {
             // ... change the orthographic size based on the change in distance between the touches.

             float i = GetComponent<Camera>().orthographicSize + deltaMagnitudeDiff * orthoZoomSpeed;

            if( i >= maxZoom){ //if i is greater than maxZoom, set camera to max
                  GetComponent<Camera>().orthographicSize = maxZoom;
            }
            else if ( i <= minZoom){ //same but with min
                   GetComponent<Camera>().orthographicSize = minZoom;
             }
             else{ //otherwise just update it to i
                    GetComponent<Camera>().orthographicSize = i;
             }
         //...
     }
 }
}
3

What about a perspective camara??