[游戏开发]Unity 鼠标和触摸控制摄像机移动和缩放

代码

代码片

RequireComponent(typeof(Camera))]
public class CameraController : MonoBehaviour
{
    /// <summary>
    /// 摄像机
    /// </summary>
    private Camera _camera;
    /// <summary>
    /// 手指按下
    /// </summary>
    bool _fingerDown = false;
    /// <summary>
    /// 单指滑动的手指位置
    /// </summary>
    Vector3 _oneFingerDragStartPos;
    /// <summary>
    /// 双指缩放的上一帧的双指距离
    /// </summary>
    float _twoFingerLastDistance = -1;

    /// <summary>
    /// 摄像机移动最小位置
    /// </summary>
    [SerializeField] Vector2 _minPosition;
    /// <summary>
    /// 摄像机移动最大位置
    /// </summary>
    [SerializeField] Vector2 _maxPosition;
    /// <summary>
    /// 默认尺寸
    /// </summary>
    [SerializeField] float _defaultSize = 5f;
    /// <summary>
    /// 最小缩放尺寸
    /// </summary>
    [SerializeField] float _minSize;
    /// <summary>
    /// 最大缩放尺寸
    /// </summary>
    [SerializeField] float _maxSize;
    /// <summary>
    /// 缩放速度
    /// </summary>
    [SerializeField] float _scaleSpeed = 0.1f;
    /// <summary>
    /// 移动速度
    /// </summary>
    [SerializeField] float _moveSpeed = 1f;
    /// <summary>
    /// 锁定位置
    /// </summary>
    Vector3 _lockPosition;

    public Vector3 LockPosition { get => ChangePosition(_lockPosition); set => _lockPosition = value; }

    private void Awake()
    {
        _camera = GetComponent<Camera>();
    }


    private void Update()
    {
#if UNITY_EDITOR
        MouseControl();
 #else
        TouchControl();
#endif
    }

    /// <summary>
    /// 鼠标控制
    /// </summary>
    void MouseControl()
    {
        if (Input.GetMouseButtonDown(0))
        {
            _fingerDown = true;
            _oneFingerDragStartPos = GetWorldPosition(Input.mousePosition);
        }

        if (Input.GetMouseButtonUp(0))
        {
            _fingerDown = false;
            _twoFingerLastDistance = -1;
        }

        if (_fingerDown)
        {
            HandleFingerDragMove(Input.mousePosition);
        }
        var distance = Input.GetAxis("Mouse ScrollWheel");
        HandleMouseScrollWheel(distance * 10);
    }
    /// <summary>
    /// 触摸控制
    /// </summary>
    void TouchControl()
    {
        if (Input.touchCount == 2)
        {
            // 双指缩放
            HandleTwoFingerScale();
        }
        else if (Input.touchCount == 1)
        {
            if (Input.touches[0].phase == TouchPhase.Began)
            {
                _fingerDown = true;
                _oneFingerDragStartPos = GetWorldPosition(Input.mousePosition);
            }
            else if (Input.touches[0].phase == TouchPhase.Moved)
            {
                // 单指滑动
                HandleFingerDragMove(Input.touches[0].position);
            }
            _twoFingerLastDistance = -1;
        }
        else
        {
            _fingerDown = false;
            _twoFingerLastDistance = -1;
        }
    }
    /// <summary>
    /// 单指滑动
    /// </summary>
    private void HandleFingerDragMove(Vector2 fingerPos)
    {
        //滑动差
        Vector3 disance = _oneFingerDragStartPos - GetWorldPosition(fingerPos);
        Vector3 newPos = _camera.transform.position;
        newPos += disance;
        newPos.Set(Mathf.Clamp(newPos.x, _minPosition.x, _maxPosition.x), Mathf.Clamp(newPos.y, _minPosition.y, _maxPosition.y), -10);
        _camera.transform.position = newPos;
    }

    /// <summary>
    /// 双指缩放
    /// </summary>
    private void HandleTwoFingerScale()
    {
        float distance = Vector2.Distance(Input.touches[0].position, Input.touches[1].position);
        if (_twoFingerLastDistance == -1)
        {
            _twoFingerLastDistance = distance;
        }
        // 与上一帧比较变化
        float scale = _scaleSpeed * (distance - _twoFingerLastDistance);
        ScaleCamere(scale);
        _twoFingerLastDistance = distance;
    }

    /// <summary>
    /// 鼠标滚轮缩放
    /// </summary>
    /// <param name="distance"></param>
    private void HandleMouseScrollWheel(float distance)
    {
        if (distance == 0) return;
        ScaleCamere(distance);
    }

    /// <summary>
    /// 缩放摄像机的视口
    /// </summary>
    /// <param name="scale"></param>
    private void ScaleCamere(float scale)
    {
        _camera.orthographicSize = Mathf.Clamp(_camera.orthographicSize - scale * _scaleSpeed, _minSize, _maxSize);
    }

    /// <summary>
    /// 屏幕坐标换算成3D坐标
    /// </summary>
    /// <param name="screenPos">屏幕坐标</param>
    /// <returns></returns>
    Vector3 GetWorldPosition(Vector2 screenPos)
    {
        return _camera.ScreenToWorldPoint(new Vector3(screenPos.x, screenPos.y, 0));
    }
    /// <summary>
    /// 修改世界坐标的Z值
    /// </summary>
    /// <param name="worldPositon">世界坐标</param>
    /// <returns></returns>
    Vector3 ChangePosition(Vector3 worldPositon)
    {
        worldPositon.x = -10;
        return worldPositon;
    }
    public void M_BackRS()
    {
        _camera.transform.position = _lockPosition;
        _camera.orthographicSize = _defaultSize;
    }
    /// <summary>
    /// 摄像机聚焦中心点
    /// </summary>
    /// <param name="center">中心点</param>
    public void M_CameraFocusing(Vector3 center)
    {
        _camera.transform.position.Set(center.x, center.y, -10f);
    }
}