OrbitCamera.cs

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using UnityEngine;
 
 
public class OrbitCamera : MonoBehaviour
{
    // ------------------------------------------------------------------
    // Inspector fields
    // ------------------------------------------------------------------
 
 
    public Transform target;
 
    public float distance = 3f;
 
 
 
    public float autoRotateSpeed = 20f;
 
    public bool autoRotate = true;
 
 
 
    public float mouseSensitivity = 200f;
 
    public float minVerticalAngle = -20f;
 
    public float maxVerticalAngle = 70f;
 
 
 
    public float scrollSensitivity = 5f;
 
    public float minDistance = 1.5f;
 
    public float maxDistance = 8f;
 
 
    // ------------------------------------------------------------------
    // Private state
    // ------------------------------------------------------------------
 
    private float   _yaw;             
    private float   _pitch = 20f;     
    private bool    _isDragging;      
    private Vector2 _lastMousePos;    
 
    // ------------------------------------------------------------------
    // Unity lifecycle
    // ------------------------------------------------------------------
 
    void Start() => UpdatePosition();
 
    void LateUpdate()
    {
        HandleMouseInput();
 
        if (autoRotate && !_isDragging)
            _yaw += autoRotateSpeed * Time.deltaTime;
 
        UpdatePosition();
    }
 
    // ------------------------------------------------------------------
    // Private helpers
    // ------------------------------------------------------------------
 
    void HandleMouseInput()
    {
        if (Input.GetMouseButtonDown(0))
        {
            _isDragging   = true;
            _lastMousePos = Input.mousePosition;
        }
 
        if (Input.GetMouseButtonUp(0))
            _isDragging = false;
 
        if (_isDragging)
        {
            Vector2 delta = (Vector2)Input.mousePosition - _lastMousePos;
            _yaw   += delta.x * mouseSensitivity * Time.deltaTime;
            _pitch -= delta.y * mouseSensitivity * Time.deltaTime;
            _pitch  = Mathf.Clamp(_pitch, minVerticalAngle, maxVerticalAngle);
            _lastMousePos = Input.mousePosition;
        }
 
        float scroll = Input.GetAxis("Mouse ScrollWheel");
        if (Mathf.Abs(scroll) > 0.001f)
        {
            distance -= scroll * scrollSensitivity;
            distance  = Mathf.Clamp(distance, minDistance, maxDistance);
        }
    }
 
    void UpdatePosition()
    {
        if (target == null) return;
        Quaternion rotation = Quaternion.Euler(_pitch, _yaw, 0f);
        transform.position  = target.position + rotation * (Vector3.back * distance);
        transform.LookAt(target.position);
    }
 
    // ------------------------------------------------------------------
    // Public API
    // ------------------------------------------------------------------
 
    public void ToggleAutoRotate() => autoRotate = !autoRotate;
 
    public bool IsAutoRotating => autoRotate;
 
    public void ResetView()
    {
        _yaw     = 0f;
        _pitch   = 20f;
        distance = 3f;
    }
}