WaterFlush/Assets/AIPagedLod/Scripts/WebGL/CameraBirdSec.cs

using System;
using System.Collections.Generic;
using DG.Tweening;
using Unity.Mathematics;
using Unity.VisualScripting;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;

public class CameraBirdSec : MonoBehaviour
{
    public Action beginDrag;

    public float smoothSpeed = 0.125f; // 摄像头平滑移动的速度
    public float scrollSensitivity = 5f; // 鼠标滚轮的灵敏度
    public float rotateSpeed = 0.25f;
    public float translateSpeed = 3f;
    public float minDistance = 5f; // 摄像头与目标对象的最小距离
    public float maxDistance = 50f; // 摄像头与目标对象的最大距离

    public float currentDistance; // 当前摄像头与目标对象的距离
    private Vector3 velocity = Vector3.zero; // 摄像头移动的速度
    private bool isDragging = false; // 是否正在拖拽
    private Vector3 lastMousePosition; // 上一帧鼠标位置

    public Canvas canvas;

    public float rotateYAngle = 0.0f;
    public float rotateXAngle = 0.0f;

    public Action<float> OnDistanceChange;

    public float min_X;
    public float max_X;
    public float min_Y;
    public float max_Y;

    public bool fixMoveRange = false;
    public bool detailLod = false;

    bool onUI = false;

    private Camera _camera;

    void Start()
    {
        _camera = this.GetComponent<Camera>();
    }

    private bool GetPointerOverUIElement(out GameObject uiElement)
    {
        uiElement = null;
        PointerEventData pointerEventData = new PointerEventData(EventSystem.current)
        {
            position = Input.mousePosition
        };

        RaycastResult raycastResult = new RaycastResult();
        List<RaycastResult> results = new List<RaycastResult>();
        GraphicRaycaster raycaster = canvas.GetComponent<GraphicRaycaster>();

        if (raycaster != null)
        {
            raycaster.Raycast(pointerEventData, results);
            if (results.Count > 0)
            {
                raycastResult = results[0];
                uiElement = raycastResult.gameObject;
                return true;
            }
        }

        return false;
    }

    private bool IsPointerOverUIElement()
    {
        bool specialUI = false;
        if (GetPointerOverUIElement(out GameObject uiElement))
        {
            // 获取 UI 元素的类型
            if (uiElement.TryGetComponent<Button>(out Button button))
            {
                if (uiElement.transform.TryGetComponent<RuntimePoint>(out RuntimePoint rp))
                {
                    specialUI = true;
                }
            }
        }

        // 检查当前鼠标位置是否在 UI 上
        return EventSystem.current.IsPointerOverGameObject() && !specialUI;
    }

    void LateUpdate()
    {
        onUI = false;
        if (IsPointerOverUIElement()) onUI = true;

        translateSpeed = currentDistance / 1000.0f;
        // 鼠标滚轮控制摄像头远近
        if (Input.GetAxis("Mouse ScrollWheel") != 0 && !onUI)
        {
            //定一个鼠标在地图上的位置
            var mousePosOnMap = Input.mousePosition;
            mousePosOnMap.z = math.abs(-582 - this.transform.position.z);
            mousePosOnMap = _camera.ScreenToWorldPoint(mousePosOnMap);

            var cameraPosOnMap = this.transform.position;
            cameraPosOnMap.z = -582;

            var distance_y = Vector3.Distance(cameraPosOnMap, this.transform.position);
            var distance_x = Vector3.Distance(cameraPosOnMap, mousePosOnMap);
            var dir_x = (mousePosOnMap - cameraPosOnMap).normalized;
            
            
            if (detailLod)
            {
                scrollSensitivity = math.clamp(currentDistance, 0, 10);
                // 更新当前距离
                currentDistance -= Input.GetAxis("Mouse ScrollWheel") * scrollSensitivity;
                // 确保距离在允许的范围内
                currentDistance = Mathf.Clamp(currentDistance, minDistance, maxDistance);

                //this.GetComponent<DepthFog>().Height = 400000 / currentDistance;
                OnDistanceChange?.Invoke(currentDistance);
            }
            else
            {
                OnDistanceChange?.Invoke(Input.GetAxis("Mouse ScrollWheel"));
            }
            Vector3 targetPosition = transform.position;
            targetPosition.z = -582 - currentDistance;

            var distance_y_after = Vector3.Distance(targetPosition, cameraPosOnMap);
            var targetScale = distance_y_after / distance_y;

            var moveDistance = (distance_x * targetScale)-distance_x;

            var finalPos = targetPosition - dir_x * moveDistance;
            
            //限制移动范围
            if (fixMoveRange)
            {
                Vector3 finalPos_Fix = finalPos;
                finalPos_Fix.x = Mathf.Clamp(finalPos_Fix.x, min_X, max_X);
                finalPos_Fix.y = Mathf.Clamp(finalPos_Fix.y, min_Y, max_Y);
                finalPos = finalPos_Fix;
            }
            
            transform.position = finalPos;
        }

        // 鼠标左键拖拽平移摄像头
        if (Input.GetMouseButtonDown(1) && !onUI)
        {
            beginDrag?.Invoke();
            isDragging = true;
            lastMousePosition = Input.mousePosition;
        }
        else if (Input.GetMouseButtonUp(1))
        {
            isDragging = false;
        }
        
        if (isDragging)
        {
            // 计算鼠标移动的偏移量
            Vector3 mouseOffset = Input.mousePosition - lastMousePosition;
            // 根据偏移量计算摄像头的目标位置
            Vector3 moveDirection = Vector3.down * mouseOffset.y * translateSpeed +
                                    Vector3.left * mouseOffset.x * translateSpeed;
            
            Vector3 targetPosition=transform.position+ moveDirection;
            //限制移动范围
            if (fixMoveRange)
            {
                Vector3 finalPos = targetPosition;
                finalPos.x = Mathf.Clamp(finalPos.x, min_X, max_X);
                finalPos.y = Mathf.Clamp(finalPos.y, min_Y, max_Y);
                targetPosition = finalPos;
            }
            transform.position = targetPosition;
        }
        lastMousePosition = Input.mousePosition;
    }
    
    public void SetRange(float _minX, float _maxX, float _minY, float _maxY)
    {
        min_X = _minX;
        max_X = _maxX;
        min_Y = _minY;
        max_Y = _maxY;

        //限制移动范围
        if (fixMoveRange)
        {
            Vector3 finalPos = transform.position;
            finalPos.x = Mathf.Clamp(finalPos.x, min_X, max_X);
            finalPos.y = Mathf.Clamp(finalPos.y, min_Y, max_Y);
            transform.position = finalPos;
        }
    }


    public void SetCameraToCenterFade(Vector3 centerPos, float distance = 300)
    {
        MeshRenderer fader = this.transform.GetChild(0).GetComponent<MeshRenderer>();
        fader.gameObject.SetActive(true);
        fader.material.DOColor(Color.white, 0.1f).onComplete = () =>
        {
            fader.material.DOColor(Color.clear, 1.5f).onComplete = () => { fader.gameObject.SetActive(false); };
        };
        centerPos.z = -582 - currentDistance;
        transform.position = centerPos;
    }
}