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

[RequireComponent(typeof(MeshFilter))]
public class MeshGen : MonoBehaviour
{
    Mesh mesh;

    Vector3[] vertices;
    int[] triangles;

    public int xSize = 10;
    public int zSize = 10;

    private void Start()
    {
        mesh = new Mesh();
        mesh.indexFormat = UnityEngine.Rendering.IndexFormat.UInt32;
        GetComponent<MeshFilter>().mesh = mesh;

        CreateShape();
        UpdateMesh();
    }



    private void CreateShape()
    {
        vertices = new Vector3[(xSize + 1) * (zSize + 1)];

        for (int i = 0, z = 0; z <= zSize; z++)
        {
            for (int x = 0; x <= xSize; x++)
            {
                vertices[i] = new Vector3(x, 2, z);
                i++;
            }
        }

        triangles = new int[xSize * zSize * 6];

        int vert = 0;
        int tris = 0;

        for (int z = 0; z < zSize; z++)
        {
            for (int x = 0; x < xSize; x++)
            {
                triangles[tris + 0] = vert + 0;
                triangles[tris + 1] = vert + xSize + 1;
                triangles[tris + 2] = vert + 1;
                triangles[tris + 3] = vert + 1;
                triangles[tris + 4] = vert + xSize + 1;
                triangles[tris + 5] = vert + xSize + 2;

                vert++;
                tris += 6;

            }
            vert++;
         }
    }

    void UpdateMesh()
    {
        mesh.Clear();

        mesh.vertices = vertices;
        mesh.triangles = triangles;

        mesh.RecalculateNormals();
        mesh.RecalculateBounds();
        mesh.RecalculateTangents();
    }

   /* private void OnDrawGizmos()
    {
        if (vertices == null)
            return;

        for (int i = 0; i < vertices.Length; i++)
        {
            Gizmos.DrawSphere(vertices[i], .1f);
        }
    }
    */

}