CharTPSCamera_v5.cs

using UnityEngine;

class CharTPSCamera : MonoBehaviour
{

    public static CharTPSCamera instance;
    public Transform target;

    public float Distance { get; set; }

    private const float _START_DISTANCE = 2f;
    private const float _DISTANCE_MIN = _START_DISTANCE;
    private const float _DISTANCE_MAX = 12f;
    private const float _DISTANCE_SMOOTH = 0.05f;

    private const float _X_SMOOTH = 0.05f;
    private const float _Y_SMOOTH = 0.1f;

    private float _velDistance;

    //Скорости движения по соответствующим осям
    private float _velX;
    private float _velY;
    private float _velZ;

    private float _mouseX;
    private float _mouseY;

    private float _desireDistance;
    private Vector3 _desirePosition;

    //Окончательная позиция камеры
    private Vector3 _position;

    private const float _X_MOUSE_SENSITIVITY = 5f;
    private const float _Y_MOUSE_SENSITIVITY = 5f;
    private const float _MOUSE_WHEEL_SENSITIVITY = 5f;
    private const float _DEAD_ZONE = 0.01f;

    private const float _Y_MIN_LIMIT = -40f;
    private const float _Y_MAX_LIMIT = 80f;

    void Awake()
    {
        instance = this;
    }

    void Start()
    {
        Reset();
    }

    void LateUpdate()
    {
        if (target == null) return;
        PlayerInput();
        CalcDesirePosition();
        UpatePosition();
    }

    private void PlayerInput()
    {
        if (Input.GetMouseButton(1))
        {
            _mouseX += Input.GetAxis("Mouse X") * _X_MOUSE_SENSITIVITY;
            _mouseY -= Input.GetAxis("Mouse Y") * _Y_MOUSE_SENSITIVITY;
        }

        _mouseY = Helper.ClampAngle(_mouseY, _Y_MIN_LIMIT, _Y_MAX_LIMIT);
        float scroll = Input.GetAxis("Mouse ScrollWheel");

        if (scroll < -_DEAD_ZONE || scroll > _DEAD_ZONE)
        {
            _desireDistance = Mathf.Clamp(Distance - scroll * _MOUSE_WHEEL_SENSITIVITY, _DISTANCE_MIN, _DISTANCE_MAX);
        }
    }

    private void CalcDesirePosition()
    {
        Distance = Mathf.SmoothDamp(Distance, _desireDistance, ref _velDistance, _DISTANCE_SMOOTH);
        _desirePosition = CalcPosition(_mouseY, _mouseX, Distance);
    }

    private Vector3 CalcPosition(float rotx, float roty, float distance)
    {
        Vector3 direction = new Vector3(0, 0, -distance);
        Quaternion rotation = Quaternion.Euler(rotx, roty, 0);

        return target.position + rotation * direction;
    }

    public void Reset()
    {
        _mouseX = 0;
        _mouseY = 10f;

        Distance = _START_DISTANCE;
        _desireDistance = Distance;
    }

    private void UpatePosition()
    {

        //Сглаживаем движения по соответствующим осям
        float posX = Mathf.SmoothDamp(_position.x, _desirePosition.x, ref _velX, _X_SMOOTH);
        float posY = Mathf.SmoothDamp(_position.y, _desirePosition.y, ref _velY, _Y_SMOOTH);
        float posZ = Mathf.SmoothDamp(_position.z, _desirePosition.z, ref _velZ, _X_SMOOTH);

        //Формируем вектор - окончательное положение камеры
        _position = new Vector3(posX, posY, posZ);

        //Перемещаем камеру в рассчитанное положение
        transform.position = _position;

        //Поворачиваем камеру так, чтобы она глядела на цель
        transform.LookAt(target);
    }

    static public void GetCamera()
    {

        GameObject tempCamera;
        GameObject targetTemp;

        CharTPSCamera myCamera;

        if (Camera.mainCamera != null) tempCamera = Camera.mainCamera.gameObject;
        else
        {
            tempCamera = new GameObject("Main Camera");
            tempCamera.AddComponent("Camera");
            tempCamera.tag = "Main Camera";
        }

        tempCamera.AddComponent("CharTPSCamera");
        myCamera = tempCamera.GetComponent<CharTPSCamera>();

        targetTemp = GameObject.Find("targetLookAt");

        if (targetTemp == null)
        {
            targetTemp = new GameObject("targetLookAt");
            targetTemp.transform.position = Vector3.zero;
        }

        myCamera.target = targetTemp.transform;
    }
}

internal static class Helper
{

    public static float ClampAngle(float angle, float min, float max)
    {
        do
        {
            if (angle < -360) angle += 360;
            if (angle > 360) angle -= 360;
        } while (angle < -360 || angle > 360);

        return Mathf.Clamp(angle, min, max);
    }
}