unity 读取灰度图生成按高程分层设色地形模型

准备灰度图

1、高程按比例对应hue色相(hsv)生成mesh效果
o.color = float4(hsv2rgb(float3(v.vertex.y/100.0, 0.5, 0.75)), 1.0);

unity shader

Shader "Unlit/vertexColor 1"
{
	Properties
	{
		_MainTex ("Texture", 2D) = "white" {}
	}
	SubShader
	{
		Tags { "RenderType"="Opaque" }
		LOD 100

		Pass
		{
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			// make fog work
			#pragma multi_compile_fog

			#include "UnityCG.cginc"

			struct appdata
			{
				float4 vertex : POSITION;
				float2 uv : TEXCOORD0;
			};

			struct v2f
			{
				float2 uv : TEXCOORD0;
				UNITY_FOG_COORDS(1)
				float4 vertex : SV_POSITION;
				float4 color:COLOR;
			};

			sampler2D _MainTex;
			float4 _MainTex_ST;

			float3 hsv2rgb(float3 c)
			{
				float4 K = float4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
				float3 p = abs(frac(c.xxx + K.xyz) * 6.0 - K.www);
				return c.z * lerp(K.xxx, saturate(p - K.xxx), c.y);
			}

			v2f vert (appdata v)
			{
				v2f o;
				o.vertex = UnityObjectToClipPos(v.vertex);
				o.uv = TRANSFORM_TEX(v.uv, _MainTex);
				o.color = float4(hsv2rgb(float3(v.vertex.y/100.0, 0.5, 0.75)), 1.0);
				UNITY_TRANSFER_FOG(o,o.vertex);
				return o;
			}

			fixed4 frag (v2f i) : SV_Target
			{
				// sample the texture
				//fixed4 col = tex2D(_MainTex, i.uv);
				fixed4 col = i.color;
				// apply fog
				UNITY_APPLY_FOG(i.fogCoord, col);
				return col;
			}
			ENDCG
		}
	}
}

　　

2、高程按比例对应色带生成mesh效果

准备色带图

unity shder

Shader "Unlit/colorRamp"
{
	Properties
	{
		_MainTex ("Texture", 2D) = "white" {}
	    _ColorRamp("Color Ramp", 2D) = "white" {}
	}
	SubShader
	{
		Tags { "RenderType"="Opaque" }
		LOD 100

		Pass
		{
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			// make fog work
			#pragma multi_compile_fog

			#include "UnityCG.cginc"

			struct appdata
			{
				float4 vertex : POSITION;
				float2 uv : TEXCOORD0;
			};

			struct v2f
			{
				float2 uv : TEXCOORD0;
				UNITY_FOG_COORDS(1)
				float4 vertex : SV_POSITION;
				float2 colorUV : TEXCOORD1;
			};

			sampler2D _MainTex;
			sampler2D _ColorRamp;
			float4 _MainTex_ST;

			v2f vert (appdata v)
			{
				v2f o;
				o.vertex = UnityObjectToClipPos(v.vertex);
				o.uv = TRANSFORM_TEX(v.uv, _MainTex);
				UNITY_TRANSFER_FOG(o,o.vertex);
				o.colorUV =  float2(v.vertex.y / 100.0,0);
				return o;
			}

			fixed4 frag (v2f i) : SV_Target
			{
				fixed4 col = tex2D(_ColorRamp,i.colorUV);
				// apply fog
				UNITY_APPLY_FOG(i.fogCoord, col);
				return col;
			}
			ENDCG
		}
	}
}

　　

mesh创建脚本

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

public class meshCreate2 : 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mes为250*250=62500
                int xNum = 1 + tGrayWidth / 250;//x方向mesh个数
                int zNum = 1 + tGrayHeight / 250; //z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 < zNum; j++)
                    {
                        if (i < xNum - 1 && j < zNum - 1)
                        {
                            meshList.Add(
                                createMesh("meshX" + i.ToString() + "Z" + j.ToString(), 251, 251,
                                i * new Vector3(2500, 0, 0) + j * new Vector3(0, 0,2500),
                                (i + 1) * new Vector3(2500, 0, 0) + (j + 1) * new Vector3(0, 0,2500) + new Vector3(10,  0,10),
                                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 < zNum - 1)
                        {
                            meshList.Add(createMesh("meshX" + i.ToString() + "Z" + j.ToString(), tGrayWidth % 250, 251,
                            i * new Vector3(2500, 0, 0) + j * new Vector3(0, 0,2500),
                            i * new Vector3(2500, 0, 0) + new Vector3(10 * (tGrayWidth % 250),  0,10) + (j + 1) * new Vector3(0, 0,2500),
                            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 == zNum - 1)
                        {
                            meshList.Add(createMesh("meshX" + i.ToString() + "Z" + j.ToString(), 251, tGrayHeight % 250,
                              i * new Vector3(2500, 0, 0) + j * new Vector3(0, 0,2500),
                             (i + 1) * new Vector3(2500, 0, 0) + j * new Vector3(0, 0,2500) + new Vector3(10, 0, 10 * (tGrayHeight % 250)),
                              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 == zNum - 1)
                        {
                            meshList.Add(createMesh("meshX" + i.ToString() + "Z" + j.ToString(), tGrayWidth % 250, tGrayHeight % 250,
                             i * new Vector3(2500, 0, 0) + j * new Vector3(0, 0, 2500),
                             i * new Vector3(2500, 0, 0) + j * new Vector3(0, 0, 2500) + new Vector3(10 * (tGrayWidth % 250),  0, 10 * (tGrayHeight % 250)),
                             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 zSetp = new Vector3(0,  0, (maxPoint.z - minPoint.z) / colF);
        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 + zSetp * j + new Vector3(0, tempZ * zScale,0);

                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 + row;
                    triangles[k++] = j * row + i + 1;

                    triangles[k++] = j * row + i + row;
                    triangles[k++] = j * row + i + row + 1;
                    triangles[k++] = j * row + i + 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;
    }
}

　　相机漫游控制脚本

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

public class MyCameraControl : MonoBehaviour
{
    public Camera mainCam;
    //旋转变量;
    private float m_deltX = 0f;
    private float m_deltY = 0f;
    //缩放变量;
    private float m_distance = 10f;
    private float m_mSpeed = 5f;
    //移动变量;
    private Vector3 m_mouseMovePos = Vector3.zero;
    //平移速度
    float Speed = 200f;

    void Start()
    {
        //  transform.localPosition = new Vector3(0, m_distance, 0);
    }

    void Update()
    {

        if (Input.GetKey(KeyCode.W))
        {
            transform.Translate(Vector3.forward * Time.deltaTime * Speed);
        }
        if (Input.GetKey(KeyCode.A))
        {
            transform.Translate(Vector3.left * Time.deltaTime * Speed);
        }
        if (Input.GetKey(KeyCode.S))
        {
            transform.Translate(Vector3.forward * Time.deltaTime * -Speed);
        }
        if (Input.GetKey(KeyCode.D))
        {
            transform.Translate(Vector3.left * Time.deltaTime * -Speed);
        }
        //鼠标左键控制旋转
        if (Input.GetMouseButton(0))
        {
            m_deltX += Input.GetAxis("Mouse X") * m_mSpeed;
            m_deltY -= Input.GetAxis("Mouse Y") * m_mSpeed;
            m_deltX = ClampAngle(m_deltX, -360, 360);//旋转幅度 左右
            m_deltY = ClampAngle(m_deltY, -70, 70);//旋转幅度 上下
            transform.rotation = Quaternion.Euler(m_deltY, m_deltX, 0);
        }
        //鼠标滑轮缩放
        if (Input.GetAxis("Mouse ScrollWheel") != 0)
        {
            //自由缩放方式;
            m_distance = Input.GetAxis("Mouse ScrollWheel") * 10f;
            transform.localPosition = transform.position + transform.forward * m_distance;
        }

        //相机位置跳到点击处;
        if (Input.GetMouseButtonDown(1)) //0-左键 1-右键 2-滑轮
        {
            Ray ray = mainCam.ScreenPointToRay(Input.mousePosition);//从摄像机发出到点击坐标的射线
            RaycastHit hitInfo;
            if (Physics.Raycast(ray, out hitInfo))
            {
                m_mouseMovePos = hitInfo.point;
                transform.localPosition = m_mouseMovePos;
            }
        }

    }

    float ClampAngle(float angle, float minAngle, float maxAgnle)
    {
        if (angle <= -360)
            angle += 360;
        if (angle >= 360)
            angle -= 360;

        return Mathf.Clamp(angle, minAngle, maxAgnle);
    }

}

本文链接

https://www.cnblogs.com/gucheng/p/10945429.html