[游戏开发]Unity绘制

一、创建空游戏对象

二、创建绘制脚本，并附给新建游戏对象

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

public class NewBehaviourScript : MonoBehaviour
{
    //记录顶点数组
    private Vector3[] vertices;
    //三角形索引
    private int[] triangles;
    //记录顶点数
    private int count;
    private Mesh mesh;
    private List<Vector3> list;
    // Start is called before the first frame update
    void Start()
    {
        //添加MeshFilter
        gameObject.AddComponent<MeshFilter>();
        //添加MeshRenderer
        gameObject.AddComponent<MeshRenderer>();
        //new一个链表
        list = new List<Vector3>();
        //获得Mesh
        mesh = GetComponent<MeshFilter>().mesh;
        //修改Material的颜色
        GetComponent<MeshRenderer>().material.color = Color.green;
        //选择材质的shader
      //  GetComponent<MeshRenderer>().material.shader = Shander.Find("Transparent/Diffuse");
        //清空所有点用于初始化
        mesh.Clear();
    }

    // Update is called once per frame
    void Update()
    {
        //点击鼠标左键
        if (Input.GetMouseButton(0))
        {
            //顶点数+1
            count++;

            //将鼠标点击的屏幕坐标转换为世界坐标，添加到list链表中
            list.Add(Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, 0.8f)));
        }
        //如果顶点数>=3 开始渲染
        if(count >= 3)
        {
            //初始化顶点数组
            vertices = new Vector3[count];
            //将list坐标赋值给顶点坐标数组
            for(int i = 0; i < count; i++)
            {
                vertices[i] = list[i];
            }
            //三角形网格数
            int trangle_count = count - 2;
            //三角形索引
            triangles = new int[3 * trangle_count];
            for(int i =0;i< trangle_count; i++)
            {
                triangles[3 * i] = 0;
                triangles[3 * i + 1] = i + 2;
                triangles[3 * i + 2] = i + 1;
            }
            //设置顶点坐标
            mesh.vertices = vertices;
            mesh.triangles = triangles;


        }
    }
}

效果如下：