Stop the camera from rotating with the mouse (c#)

Questions & Answers
1

I have a camera that rotates on the Mouse X axis however for some reason it continues to rotate slightly even when the mouse isn’t moving, the camera is attached to a capsule object as part of a third person camera. here is the code for the camera and the capsule (controller).

the controller script

using UnityEngine;
using System.Collections;

public class PlayerController : MonoBehaviour {
	
	public float movementSpeed = 10;
	public float turningSpeed = 60;
	public float jumpForce = 800;
	public Transform cameraObj;

	private Rigidbody rb;
	private bool canJump;
		
	void Awake()
	{
		rb = gameObject.GetComponent<Rigidbody> ();
	}

	void Update() 
	{
		float horizontal = cameraObj.rotation.y;
		transform.Rotate (0, horizontal, 0);
			
		float vertical = Input.GetAxis("Vertical") * movementSpeed * Time.deltaTime;
		transform.Translate (0, 0, vertical);

		float strafe = Input.GetAxis("Horizontal") * movementSpeed * Time.deltaTime;
		transform.Translate(strafe, 0, 0);

		if (Input.GetButtonDown ("Jump") == true) 
		{
			if (canJump == true)
			{
			rb.AddForce (0,jumpForce,0);
			canJump = false;
			}
		}
	}
}

The camera script

using UnityEngine;
using System.Collections;

public class ThirdPersonCamera : MonoBehaviour {

	public GameObject target;
	public float rotateSpeed = 5;

	private Vector3 offset;
	
	void Awake() 
	{
		offset = target.transform.position - transform.position;
	}
	
	void LateUpdate() 
	{
		float horizontal = Input.GetAxis("Mouse X") * rotateSpeed;
		float vertical = Input.GetAxis("Mouse Y") * rotateSpeed;
		
		target.transform.Rotate(vertical, horizontal, 0);
		
		float desiredAngle_X = target.transform.eulerAngles.x;
		float desiredAngle_Y = target.transform.eulerAngles.y;
		
		Quaternion rotation = Quaternion.Euler(desiredAngle_X, desiredAngle_Y, 0);
		transform.position = target.transform.position - (rotation * offset);
		
		transform.LookAt (target.transform);
	}
}

How do I stop the camera from moving even when the mouse is still?

2

float horizontal = cameraObj.rotation.y;
transform.Rotate(0, horizontal, 0);

For one, I do not recommend accessing the rotation property. It’s a Quaternion, so all of the values inside of it have little to do when accessed separately.

Second, that rotates the character EVERY FRAME based off of the ‘imaginary’ Y, regardles if the character is moving or not.

Removing those two lines from the code made everything stay still for me , and the character still updated its’ rotation.