基於UGUI的畫板功能

我這裏用到了Qframeworke插件。
如果不用的話你可以直接刪掉相關的代碼就可以了。
廢話不多說，先上代碼！
附上資源鏈接：我是想免費分享的，但是那個什麼積分是自動的，我沒法設置多少積分
https://download.csdn.net/download/qq_42489774/11890690

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using QFramework;
using QF.Res;
/// <summary>
/// 存儲路徑的父物體
/// </summary>
public class Mspaint : MonoBehaviour
{
    [SerializeField]
    private int state = 0;
    //畫筆顏色
    private Color paintColor = Color.red;
    [HideInInspector]
    //畫筆大小
    private float paintSize = 0.05f;
    //LineRenderer 組件
    private LineRenderer curretnLine;
    //畫筆材質
    public Material lineMaterial;
    //存儲畫線節點
    private List<Vector3> positions = new List<Vector3>();
    private bool isMouseDown = false;
    //記錄上一次節點位置
    private Vector3 lastMousePosition = Vector3.zero;
    //圓圈的半徑
    public Slider slider;
    public GameObject CanvasX;

    //裝line盒子
    public Transform ChildrenBox;

    //是否可以執行畫畫
    bool IsPaint = true;

    //劃線，直線/圓圈等等模式
    private int Line_Mode = 0;
    public Dropdown dropdown;

    //圓圈
    Vector3 v;                   //起點，Vector2是2D,當然也可以換Vector3
    Vector3 origin;
    float R;					//半徑
    int positionCount;			//完成一個圓的總點數，
    float angle;				//轉角，三個點形成的兩段線之間的夾角
    Quaternion q;               //Quaternion四元數
                                //圓圈
    public bool IsCircle = false;
    public bool IsLine = false;
    [SerializeField]
    public RawImage RayImage;
    private Texture2D Pen;
    //private Sprite goods;
    ResLoader loader = new ResLoader();

    private void Awake()
    {
            //Value可以不用傳過去，因爲這個值可以從item中獲取；
           slider.onValueChanged.AddListener((float value) => slider.transform.GetChild(0).GetComponent<Text>().text=value.ToString());
           dropdown.onValueChanged.AddListener((int value) => Line_Mode = value);
           Pen = loader.LoadSync<Texture2D>("Pen");
          // goods = Sprite.Create(Pen, new Rect(0, 0, Pen.width, Pen.height), new Vector2(0.5f, 0.5f));
    }

    private void Update()
    {
        if (Input.GetKeyDown(KeyCode.F3))
        {
            IsPaint = !IsPaint;
            ChildrenBox.gameObject.SetActive(!IsPaint);
            CanvasX.gameObject.SetActive(!IsPaint);
            RayImage.gameObject.SetActive(!IsPaint);
            if (!IsPaint)
            {
                Cursor.SetCursor(Pen, new Vector2(0f,50f),CursorMode.ForceSoftware);
            }
            else
            {
                Cursor.SetCursor(null,new Vector2(0.5f,0.5f),CursorMode.ForceSoftware);
            }
        }
        if (Input.GetKeyUp(KeyCode.Escape))
        {
            IsPaint = true;//禁止繪畫
             ChildrenBox.gameObject.SetActive(false);
            CanvasX.gameObject.SetActive(false);
        }
        if (!IsPaint)
        {
            //撤銷功能
            if (Input.GetKeyDown(KeyCode.F2))
            {
                if (state > 0)
                {
                    Destroy(ChildrenBox.Find("Line_" + state).gameObject);
                    state--;
                }
            }
            if (Input.GetMouseButtonDown(0) && Line_Mode == 0)//自由畫線
            {
                IsLine = false;
                state++;
                //新建一個空物體
                GameObject go = new GameObject("Line_" + state);
                go.transform.SetParent(ChildrenBox);
                //給空物體添加LineRenderer組件
                curretnLine = go.AddComponent<LineRenderer>();
                //設置材質
                curretnLine.material = lineMaterial;
                //畫筆大小
                curretnLine.startWidth = paintSize;
                curretnLine.endWidth = paintSize;
                //畫筆顏色
                curretnLine.startColor = paintColor;
                curretnLine.endColor = paintColor;
                //畫筆圓滑度
                curretnLine.numCornerVertices = 5;
                curretnLine.numCapVertices = 5;

                //返回射線和平面交點位置
                Vector3 position = GetMousePoint();
                //添加畫線路勁節點(Vector3)
                AddPosition(position);
                isMouseDown = true;
            }
            else if (Input.GetMouseButtonDown(0) && Line_Mode == 1)//
            {
                IsLine = false;
                state++;
                //新建一個空物體
                GameObject go = new GameObject("Line_" + state);
                go.transform.SetParent(ChildrenBox);
                //給空物體添加LineRenderer組件
                curretnLine = go.AddComponent<LineRenderer>();
                //設置材質
                curretnLine.material = lineMaterial;
                //畫筆大小
                curretnLine.startWidth = paintSize;
                curretnLine.endWidth = paintSize;
                //畫筆顏色
                curretnLine.startColor = paintColor;
                curretnLine.endColor = paintColor;
                //畫筆圓滑度
                curretnLine.numCornerVertices = 5;
                curretnLine.numCapVertices = 5;

                v = GetMousePoint();
               // R = 6;
                positionCount = 180;
                angle = 360f / (positionCount - 1);
                //curretnLine = curretnLine.GetComponent<LineRenderer>();
                curretnLine.positionCount = positionCount;

                curretnLine.SetPosition(0, v);
                curretnLine.SetPosition(1, v);
                IsCircle = true;
            }
            if (IsCircle&& Line_Mode == 1)
            {
                curretnLine.SetPosition(1, GetMousePoint());
                R = Vector3.Distance(v, GetMousePoint())/2;
                origin = (v + GetMousePoint()) / 2;
                Debug.Log(R);
                DrawCircle2();
            }

            if (Input.GetMouseButtonUp(0) && Line_Mode == 1)
            {
                positionCount = 180;
                curretnLine.SetPosition(0, v);
                curretnLine.SetPosition(1, GetMousePoint());
                origin =( v + GetMousePoint())/2;
                IsCircle = false;
                DrawCircle();
                //isMouseDown = true;
                //Vector3 position = GetMousePoint();
                //////添加畫線路勁節點(Vector3)
                //AddPosition(position);
            }

            if (Input.GetMouseButtonDown(0) && Line_Mode == 2)
            {
                state++;
                //新建一個空物體
                GameObject go = new GameObject("Line_" + state);
                go.transform.SetParent(ChildrenBox);
                //給空物體添加LineRenderer組件
                curretnLine = go.AddComponent<LineRenderer>();
                //設置材質
                curretnLine.material = lineMaterial;
                //畫筆大小
                curretnLine.startWidth = paintSize;
                curretnLine.endWidth = paintSize;
                //畫筆顏色
                curretnLine.startColor = paintColor;
                curretnLine.endColor = paintColor;
                //畫筆圓滑度
                curretnLine.numCornerVertices = 5;
                curretnLine.numCapVertices = 5;


                curretnLine.positionCount = 2;//設置兩點


                Vector3 position = GetMousePoint();
                //設置指示線的起點和終點
                IsLine = true;
                curretnLine.SetPosition(0, position);
                
            }
            if (IsLine&&Line_Mode == 2)
            {
                curretnLine.SetPosition(1, GetMousePoint());
            }
            if (Input.GetMouseButtonUp(0) && Line_Mode == 2)
            {
                curretnLine.positionCount = 2;//設置兩點
                IsLine = false;
                Vector3 position = GetMousePoint();
                curretnLine.SetPosition(1, position);
            }

            void DrawCircle()
            {
                if (Line_Mode == 1)
                {
                    positionCount = 180;
                }
                else if (Line_Mode == 2)
                {
                    positionCount = 2;
                }
                for (int i = 0; i < positionCount; i++)
                {
                    if (i != 0)
                    {
                        q = Quaternion.Euler(q.eulerAngles.x, q.eulerAngles.y, q.eulerAngles.z + angle);
                    }
                    if (Line_Mode == 1)
                    {
                        Vector3 forwardPosition = (Vector3)origin + q * Vector3.down * R;//slider.value*10;
                        curretnLine.SetPosition(i, forwardPosition);
                    }
                    else if (Line_Mode == 2)
                    {
                        positionCount = 2;
                        Vector3 forwardPosition = (Vector3)origin + q * Vector3.down * R;//slider.value*10;
                        curretnLine.SetPosition(i, forwardPosition);
                    }
                  

                }
            }
            void DrawCircle2()
            {
                if (Line_Mode == 1)
                {
                    positionCount = 180;
                }
                else if (Line_Mode == 2)
                {
                    positionCount = 2;
                }
                for (int i = 0; i < positionCount; i++)
                {
                    if (i != 0)
                    {
                        q = Quaternion.Euler(q.eulerAngles.x, q.eulerAngles.y, q.eulerAngles.z + angle);
                    }
                   
                    Vector3 forwardPosition = (Vector3)origin + q * Vector3.down * R;//slider.value*10;
                    curretnLine.SetPosition(i, forwardPosition);

                }
            }

            //記錄鼠標滑過的路勁節點
            if (isMouseDown)
            {
                //返回射線和平面交點位置
                Vector3 position = GetMousePoint();
                if (Vector3.Distance(position, lastMousePosition) > 0.1f)
                {
                    //添加畫線路徑節點(Vector3)
                    AddPosition(position);
                }

            }
            //鼠標擡起時
            if (Input.GetMouseButtonUp(0))
            {
                curretnLine = null;
                //清空上一次的畫線節點 list
                positions.Clear();

                isMouseDown = false;
            }
        }
    }
    //添加畫線路勁節點(Vector3)
    void AddPosition(Vector3 position)
    {

        //讓畫線前置畫布0.1距離防止部分畫線不顯示
        position.z -= 0.1f;
        positions.Add(position);
        //
        curretnLine.positionCount = positions.Count;
        curretnLine.SetPositions(positions.ToArray());
        lastMousePosition = position;
    }
    //返回射線和平面交點位置
    Vector3 GetMousePoint()
    {
        Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
        RaycastHit hit;
        bool isCollider = Physics.Raycast(ray, out hit);
        if (isCollider)
        {
            //返回射線和平面交點位置
            return hit.point;
        }
        return Vector3.zero;
    }


    #region
    //畫布上的toggle按鈕事件
    //切換爲紅色
    public void OnRedColorChanged(bool isOn)
    {
        if (isOn)
        {
            paintColor = Color.red;
        }
    }
    //切換爲黃色
    public void OnYellowColorChanged(bool isOn)
    {
        if (isOn)
        {
            paintColor = Color.yellow;
        }
    }
    //切換爲白色
    public void OnWhiteColorChanged(bool isOn)
    {
        if (isOn)
        {
            paintColor = Color.white;
        }
    }
    //切換爲黑色
    public void OnBlackColorChanged(bool isOn)
    {
        if (isOn)
        {
            paintColor = Color.black;
        }
    }
    //設置畫線粗細 0.1
    public void OnPoint1Changed(bool isOn)
    {
        if (isOn)
        {
            paintSize = 0.05f;
        }
    }
    //設置畫線粗細 0.2

    public void OnPoint2Changed(bool isOn)
    {
        if (isOn)
        {
            paintSize = 0.1f;
        }
    }
    //設置畫線粗細 0.4

    public void OnPoint4Changed(bool isOn)
    {
        if (isOn)
        {
            paintSize = 0.2f;
        }
    }
    //清空畫布
    public void OnClearPanelButton()
    {
        state = 0;
        if (transform.childCount > 0)
        {
           
            int lineCount = ChildrenBox.childCount;
            for (int i = 0; i < ChildrenBox.childCount; i++)
            {
                Destroy(ChildrenBox.GetChild(i).gameObject);
            }
        }
    }
    #endregion
}