unity读取灰度图生成三维地形mesh

准备灰度图 IGray.png及草地贴图 IGrass.jpg ,放入Assets下StreamingAssets文件夹中。
 
 
创建空材质,用作参数传入脚本。
 
脚本如下,挂载并传入材质球即可根据灰度图生成mesh。
 
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

//根据灰度图创建mesh地形
public class MeshTerrainCreate : MonoBehaviour
{ 
    private Texture textureGray;//灰度图
    private Texture textureGrass;//草地贴图
    private int tGrayWidth = 0, tGrayHeight = 0;//灰度图的宽和高
    private bool bCreate = false;//是否完成创建
    private List<GameObject> meshList;//mesh对象集合
    private Texture2D texture2dGray;
    public float zScale=100;//高度参数

    [Tooltip("传入mesh使用的材质")]
    public Material meshMaterial;

    void Start()
    {
        StartCoroutine(loadImage("IGray.png", (t) => textureGray = t));
        StartCoroutine(loadImage("IGrass.jpg", (t) => textureGrass = t));
        meshList = new List<GameObject>();
    }

    void Update()
    {
        if (textureGray != null && textureGrass != null)
        {
            if (bCreate == false)
            {
                tGrayWidth = textureGray.width;
                tGrayHeight = textureGray.height;
                meshMaterial.mainTexture = textureGrass;//设置材质贴图
                //mesh顶点数目最大65000,则取mesh顶点为250*250=62500
                int xNum = 1+tGrayWidth / 250;//x方向mesh个数
                int yNum = 1+tGrayHeight / 250; //y方向mesh个数
                texture2dGray = (Texture2D)textureGray;
                //根据灰度图创建mesh
                for (int i = 0; i <xNum; i++)
                {
                    for (int j = 0; j <yNum; j++)
                    {
                        if (i < xNum-1 && j < yNum-1)
                        {
                            meshList.Add(
                                createMesh("meshX" + i.ToString() + "Y" + j.ToString(),  251, 251, 
                                i * new Vector3(2500, 0, 0) + j * new Vector3(0, 2500, 0), 
                                (i + 1) * new Vector3(2500, 0, 0) + (j + 1) * new Vector3(0, 2500, 0)+new Vector3(10,10,0),
                                i * new Vector2(250, 0) + j * new Vector2(0, 250),
                                (i + 1) * new Vector2(250, 0) + (j + 1) * new Vector2(0, 250)+new Vector2(1,1)));
                        }
                        else if (i == xNum-1 && j < yNum-1)
                        {
                            meshList.Add(createMesh("meshX" + i.ToString() + "Y" + j.ToString(), tGrayWidth%250, 251,
                            i * new Vector3(2500, 0, 0) + j * new Vector3(0, 2500, 0),
                            i* new Vector3(2500, 0, 0)+new Vector3(10*(tGrayWidth % 250),10,0) + (j + 1) * new Vector3(0, 2500, 0),
                            i * new Vector2(250, 0) + j * new Vector2(0, 250),
                            i  * new Vector2(250, 0)+new Vector2(tGrayWidth % 250,1) + (j + 1) * new Vector2(0, 250)));
                        }
                        else if (i < xNum-1 && j == yNum-1)
                        {
                            meshList.Add(createMesh("meshX" + i.ToString() + "Y" + j.ToString(),251, tGrayHeight%250,
                              i * new Vector3(2500, 0, 0) + j * new Vector3(0, 2500, 0),
                             (i + 1) * new Vector3(2500, 0, 0) + j * new Vector3(0, 2500, 0)+new Vector3(10,10* (tGrayHeight % 250),0),
                              i * new Vector2(250, 0) + j * new Vector2(0, 250),
                             (i + 1) * new Vector2(250, 0) + j * new Vector2(0, 150)+new Vector2(1, tGrayHeight % 250) ) );
                        }
                        else if (i == xNum-1 && j == yNum-1)
                        {
                            meshList.Add(createMesh("meshX" + i.ToString() + "Y" + j.ToString(),tGrayWidth%250,tGrayHeight%250,
                             i * new Vector3(2500, 0, 0) + j * new Vector3(0, 2500, 0),
                             i  * new Vector3(2500, 0, 0) + j  * new Vector3(0, 2500, 0)+new Vector3(10 * (tGrayWidth % 250), 10 * (tGrayHeight % 250),0),
                             i * new Vector2(250, 0) + j * new Vector2(0, 250),
                             i  * new Vector2(250, 0) + j  * new Vector2(0, 250) +new Vector2(tGrayWidth % 250, tGrayHeight % 250)) );
                        }
                    }
                }
                bCreate = true;
            }
        }
    }

    //加载图片
    IEnumerator loadImage(string imagePath, System.Action<Texture> action)
    {
        WWW www = new WWW("file://" + Application.streamingAssetsPath + "/" + imagePath);
        yield return www;
        if (www.error == null)
        {
            action(www.texture);
        }
    }


    /// <summary>
    ///创建mesh 
    /// </summary>
    /// <param name="meshName">mesh名称</param>
    /// <param name="row">行数</param>
    /// <param name="col">列数</param>
    /// <param name="minPoint">最小点位置</param>
    /// <param name="maxPoint">最大点位置</param>
    /// <param name="minImgPosition">最小点灰度图位置</param>
    /// <param name="maxImgPosition">最大点灰度图位置</param>
    /// <returns></returns>
    /// 


    private GameObject createMesh(string meshName, int row, int col, Vector3 minPoint, Vector3 maxPoint, Vector2 minImgPosition, Vector2 maxImgPosition)
    {
        GameObject meshObject = new GameObject(meshName);

        int verticeNum = row * col;
        Vector3[] vertices = new Vector3[verticeNum];//顶点数组大小 
        int[] triangles = new int[verticeNum * 3 * 2];//三角集合数组,保存顶点索引 
                                                      // Vector3[] normals = new Vector3[verticeNum];//顶点法线数组大小
        Vector2[] uvs = new Vector2[verticeNum];
        float rowF = (float)row;
        float colF = (float)col;
        Vector3 xStep = new Vector3((maxPoint.x - minPoint.x) / rowF, 0, 0);
        Vector3 ySetp = new Vector3(0, (maxPoint.y - minPoint.y) / colF, 0);
        int k = 0;
        
        for (int i = 0; i < row; i++)
        {
            for (int j = 0; j < col; j++)
            {
                float tempZ = texture2dGray.GetPixel((int)minImgPosition.x + i, (int)minImgPosition.y + j).grayscale;
                vertices[i + j * row] = minPoint + xStep * i + ySetp * j+new Vector3(0,0,tempZ* zScale);
               
                uvs[i + j * row] = new Vector2((float)i / rowF, (float)j / colF);

                if (j < col - 1 && i < row - 1)
                {
                    triangles[k++] = j * row + i;
                    triangles[k++] = j * row + i + 1;
                    triangles[k++] = j * row + i + row;

                    triangles[k++] = j * row + i + row;
                    triangles[k++] = j * row + i + 1;
                    triangles[k++] = j * row + i + row + 1;
                }
            }
        }
        Mesh mesh = new Mesh();
        mesh.vertices = vertices;
        mesh.triangles = triangles;
        // mesh.normals = normals;
        mesh.uv = uvs;
        mesh.RecalculateBounds();
        mesh.RecalculateNormals();
        meshObject.AddComponent<MeshFilter>();
        meshObject.AddComponent<MeshRenderer>();
        meshObject.GetComponent<MeshFilter>().mesh = mesh;
        meshObject.GetComponent<MeshRenderer>().material = meshMaterial;

        return meshObject;
    }
}

效果如下

 
原文地址:https://www.cnblogs.com/gucheng/p/10104873.html