using UnityEngine;
using System.Collections;

public class Radar : MonoBehaviour
{
    //网格模型顶点数量
    private int VERTICES_COUNT;
    //大小
    public float scale = 1;

    [Tooltip("边数为数组长度减1")]
    //顶点数组
    private Vector3[] vertices = new Vector3[6] ;
    //三角形数组
    int[] triangles;

    //每条边的长度设置
    private float[] edgeSizes = new float[6];
    //基础长度
    public float baseSize = 0.01f;

    MeshFilter meshFilter;
    Mesh mesh;

    float pi = 3.1415f;
    void Start()
    {   
        CreateMesh();
        SetVertices();
    }

    void OnGUI()
    {
        //if (meshFilter == null)
        //{
        //    CreateMesh(); 
        //    SetVertices();
        //}
        // Fresh(); // 这个是刷新
        //if (GUILayout.Button("Fresh"))
        //{
        //    Fresh();
        //}

        //if (GUILayout.Button("Set"))
        //{
        //    SetVerticeLength(10);
        //}
        //if (GUILayout.Button("SetEdgeSizes"))
        //{
        //    SetEdgeSizes(10, 0.5f);
        //}

    }

    void CreateMesh()
    {
        meshFilter = (MeshFilter)GetComponent(typeof(MeshFilter)); //GameObject.Find("radar")
        mesh = meshFilter.mesh;
    }

    void SetVertices()
    {
        VERTICES_COUNT = vertices.Length;
        int triangles_count = VERTICES_COUNT - 1;

        triangles = new int[triangles_count * 3];

        //设定原点坐标
        vertices[0] = new Vector3(0, 0, 1);
        //首个在x轴上的坐标点
        vertices[1] = new Vector3(45, 0, 1);
        //每个三角形角度
        float everyAngle = 360 / triangles_count;

        for (int i = 1; i < vertices.Length; i++)
        {
            var angle = GetRadians(everyAngle * (i - 1));
            vertices[i] = new Vector3(45 * Mathf.Cos(angle), 45 * Mathf.Sin(angle), 1);
        }

        int idx = 0;
        int value = 0;
        for (int i = 0; i < triangles.Length; i++)
        {
            if (i % 3 == 0)
            {
                triangles[i] = 0;
                value = idx;
                idx++;
            }
            else
            {
                value++;
                if (value == VERTICES_COUNT)
                    value = 1;
               // Debug.Log("value " + value);
                triangles[i] = value;
            }
        }
    }

    float GetRadians(float angle)
    {
        return pi / 180 * angle;
    }

    void Apply()
    {
        Vector3[] tmps = new Vector3[vertices.Length];
        for (int i = 0; i < vertices.Length; i++)
        {
            tmps[i] = vertices[i] * vertices[i].z * scale * (baseSize + edgeSizes[i]);
        }
        if (mesh == null) {
            CreateMesh();
        }
        mesh.vertices = tmps;
        mesh.triangles = triangles;
    }


    /// <summary>
    /// 设置几边形
    /// </summary>
    /// <param name="num"></param>
    public void SetVerticeLength(int num)
    {
        if (num>=3)
        {
            vertices = new Vector3[num + 1];
            edgeSizes = new float[num + 1];
            SetVertices();
        }

    }

    /// <summary>
    /// 设置每条边的值
    /// </summary>
    /// <param name="i"></param>
    /// <param name="value"></param>
    public void SetEdgeSizes(int i,float value)
    {
        if (edgeSizes.Length > i)
        {
            edgeSizes[i] = value;
        }

    }


    /// <summary>
    /// 刷新绘制
    /// </summary>
    public void Fresh()
    {
        Apply();
    }
}