Unity中使用填充Mesh顶点的方法绘制伤害区域范围

using UnityEngine;
using System.Collections;
using System.Collections.Generic;

[RequireComponent(typeof(MeshFilter), typeof(MeshRenderer))]

//public static class meshDraw : MonoBehaviour {
public class MeshDraw : MonoBehaviour {
    private Vector3 point = Vector3.right;
    private int numberOfPoint = 10;
    private Mesh mesh;
    private Vector3[] vertices;
    private int[] triangles;
    private Material meshMaterial;
    private float lastTime = 1f;
    private Material _material;
    //public Transform heroTransform;
    
    public static  Color COLOR_GREEN = new Color (1,0,0,0.2f);
    public static Color COLOR_RED = new Color (1,0,0,0.2f);

    void Start () {
        GetComponent<MeshFilter> ().mesh = mesh = new Mesh ();
        mesh.name = "areaMesh";
        _material = GetComponent<MeshRenderer>().material;
        _material.color = COLOR_GREEN;
    }
    
　　 //旧版的绘制圆形方法，留下来做一个参考
//    public void DrawCicle()// Old one.Abandened！
    //    {
    //        mesh.Clear ();
    //        vertices = new Vector3[numberOfPoint + 1];
    //        triangles = new int[numberOfPoint * 3];
    //        float angle = - 360f / numberOfPoint;
    //        for (int v = 1, t = 1; v <vertices.Length; v++, t = t + 3) {
    //            vertices [v] = Quaternion.Euler (0f, 0f, angle * (v - 1)) * point;
    //            triangles[t] = v;
    //            triangles [t + 1] = v + 1;
    //        }
    //        triangles [triangles.Length - 1] = 1;
    //        mesh.vertices = vertices;
    //        mesh.triangles = triangles;
    //        mesh.RecalculateBounds ();
    //    }
    //  

　　//srcPosi，所需绘制的坐标。
    private void AdjustPosition(Vector3 srcPosi)
    {
        srcPosi.y += 0.1f;
        transform.position = srcPosi;
    }

　　//绘制矩形范围
    public void DrawRect(Vector3 srcPosi, float pRectWidth, float pRectHeight)
    {
        mesh.Clear ();
        AdjustPosition(srcPosi);
        Vector3[] vertics = new Vector3[4];
        vertics [0] = new Vector3 (pRectWidth / 2, 0, 0);
        vertics [1] = new Vector3 (-pRectWidth / 2, 0, 0);
        vertics [2] = new Vector3 (-pRectWidth / 2, 0, pRectHeight);
        vertics [3] = new Vector3 (pRectWidth / 2, 0, pRectHeight);
        
        int[] indics = new int[6];
        indics [0] = 0; indics [1] = 1; indics [2] = 2;
        indics [3] = 0; indics [4] = 2; indics [5] = 3;
        
        mesh.vertices = vertics;
        mesh.triangles = indics;
        mesh.RecalculateBounds ();
        StartCoroutine (ClearMeshInfo ());
    }
    
　　//绘制直线，采用宽度为0.1的矩形进行模拟
    public void DrawLine(Vector3 srcPosi, float pLineLenth)
    {
        DrawRect (srcPosi, 0.1f, pLineLenth);
    }


　　//绘制梯形，和绘制矩形基本上一个思路。
    public void DrawTrapezoid(Vector3 srcPosi, float pRectWidth, float pRectHeight, float cutLength)
    {
        mesh.Clear ();
        AdjustPosition(srcPosi);
        Vector3[] vertics = new Vector3[4];
        vertics [0] = new Vector3 (pRectWidth / 2 - cutLength, 0, 0);
        vertics [1] = new Vector3 (-pRectWidth / 2 + cutLength, 0, 0);
        vertics [2] = new Vector3 (-pRectWidth / 2, 0, pRectHeight);
        vertics [3] = new Vector3 (pRectWidth / 2, 0, pRectHeight);
        
        int[] indics = new int[6];
        indics [0] = 0; indics [1] = 1; indics [2] = 2;
        indics [3] = 0; indics [4] = 2; indics [5] = 3;
        
        mesh.vertices = vertics;
        mesh.triangles = indics;
        mesh.RecalculateBounds ();
        StartCoroutine (ClearMeshInfo ());
    }

    public void SetColor(Color color)
    {
        _material.color = color;
    }
　　
　　//绘制圆形，扇形，圆环，部分圆环。
　　//radiusLong 外径的长度，
　　//radiusShort 内径的长度，圆形， 扇形的时候，此值为0
　　//angle 绘制角度，圆形，圆环为360， 其他情况根据需要设置
　　//useMiniAngle 预留参数，未实现功能。
    public void DrawSector(Vector3 srcPosi, float radiusLong, float radiusShort, float angle, bool useMiniAngle)
    {
        mesh.Clear ();
        AdjustPosition(srcPosi);

        Matrix4x4 matrix = GetYAxisMatrix (1);
        Vector3 posShort = new Vector3 (radiusShort, 0, 0);
        Vector3 posLong = new Vector3 (radiusLong, 0, 0);
        List<Vector3> verticsTemp = new List<Vector3> ();
        Vector3 posShort0;
        Vector3 posLonge0;
        verticsTemp.Add (posShort);
        verticsTemp.Add (posLong);
        for (int i = 0; i < angle / 1; i++) {
            posShort0 = matrix.MultiplyVector(posShort);
            posLonge0 = matrix.MultiplyVector(posLong);
            verticsTemp.Add(posShort0);
            verticsTemp.Add(posLonge0);
            posShort = posShort0;
            posLong = posLonge0;
        }
        List<Vector3> vertics = new List<Vector3> ();
        List<int> triangles = new List<int> ();
        for (int i = 2; i < verticsTemp.Count; i++) {
            vertics.Add(verticsTemp[i - 2]);
            vertics.Add(verticsTemp[i - 1]);
            vertics.Add(verticsTemp[i]);
        }
        int triangleCount = vertics.Count / 3;
        for (int i = 0; i < triangleCount; i++) {
            if (i % 2 == 0) {
                triangles.Add(i * 3);
                triangles.Add(i * 3 + 1);
                triangles.Add(i * 3 +2);
            }
            else {
                triangles.Add(i * 3 + 2);
                triangles.Add(i * 3 + 1);
                triangles.Add(i * 3);
            }
        }
        
        for (int i = 0; i < vertics.Count; i++) {
            vertics[i] = Quaternion.Euler(0, 270 - angle / 2, 0) * vertics[i];
        }
        mesh.vertices = vertics.ToArray();
        mesh.triangles = triangles.ToArray();
        mesh.RecalculateBounds();
        StartCoroutine (ClearMeshInfo ());
    }
    
　　//
    public Matrix4x4 GetYAxisMatrix(float angle)
    {
        Matrix4x4 matrix = new Matrix4x4 ();
        matrix.m00 = Mathf.Cos (angle / 180 * Mathf.PI);
        matrix.m02 = Mathf.Sin (angle / 180 * Mathf.PI);
        matrix.m20 = -Mathf.Sin (angle / 180 * Mathf.PI);
        matrix.m22 = Mathf.Cos (angle / 180 * Mathf.PI);
        matrix.m11 = 1;
        return matrix;
    }

　　//延迟清除顶点信息的协程
    IEnumerator ClearMeshInfo()
    {
        yield return new WaitForSeconds (lastTime);
        mesh.Clear ();
    }
}