Mesh网格编程（二） 万能网格几何体

开头：

用一个通用代码，实现各种锥、柱、管状体的网格创建。

非原创的同系列。虽然总觉得代码上可以再优化，但是实现的功能已经超级屌了。

真是没有不能做的，只有想不到的。

具体思路：

通过Mesh网格编程实现几何体的多种变化。以立体五角星为例，大边长和小边长分别设置长度为5的数组，数组控制几何体顶层空心，顶层大小，中间层大小，底层大小，底层空心。通过循环构建上层与下层之间的网格。

代码：

using UnityEngine;using System.Collections;public class Star3 : MonoBehaviour {Mesh mesh;public bool sophisticated = false;//圆滑曲面public bool star = true;//星形public int line = 5;//边数public float[] maxsize = {0,0,5,0,0};//外角大小public float[] minSize = {0,0,1,0,0};//内角大小public float high = 1;//高度public float low = -1;//低度private Vector3[] vs;//顶点坐标private int[] ts;//顶点序列private Vector2[] newUVs;//UV贴图private Vector3[] newNormals;//法线// Update is called once per framevoid Update () {//变量约束line = Mathf.Clamp (line, 2, 300);high = Mathf.Clamp (high, low, high);low = Mathf.Clamp (low, low, high);if (!star) {for (int i = 0; i < 5; i++) {minSize[i] = Mathf.Cos(Mathf.PI / line) * maxsize[i];}}for (int i = 1; i < 4; i++) {maxsize[i] = Mathf.Clamp (maxsize[i], 0, maxsize[i]);minSize[i] = Mathf.Clamp (minSize[i], 0, maxsize[i]);}maxsize[0] = Mathf.Clamp (maxsize[0], 0, maxsize[1]);minSize[0] = Mathf.Clamp (minSize[0], 0, minSize[1]);maxsize[4] = Mathf.Clamp (maxsize[4], 0, maxsize[3]);minSize[4] = Mathf.Clamp (minSize[4], 0, minSize[3]);//角度计算float corner = 2 * Mathf.PI / line;//确定顶点数量int temp = 5 * 4 * 3 * line;vs = new Vector3[temp];ts = new int[temp];newUVs = new Vector2[temp];newNormals = new Vector3[temp];int count = 0;float h = 0;float l = 0;for (int i = 0; i < 5; i++) {switch (i) {case 0: h = high;l = high;break;case 1:h = high;l = 0;break;case 2:h = 0;l = low;break;case 3:h = low;l = low;break;case 4:h = low;l = high;break;}for (int k = 0; k < line; k++) {//确定顶点坐标vs[count] = new Vector3(Mathf.Sin(k * corner) * maxsize[i],Mathf.Cos(k * corner) * maxsize[i],h);vs[count + 1] = new Vector3(Mathf.Sin((k + 0.5f) * corner) * minSize[(i + 1) % 5],Mathf.Cos((k + 0.5f) * corner) * minSize[(i + 1) % 5],l);vs[count + 2] = new Vector3(Mathf.Sin(k * corner) * maxsize[(i + 1) % 5],Mathf.Cos(k * corner) * maxsize[(i + 1) % 5],l);vs[count + 3] = new Vector3(Mathf.Sin(k * corner) * maxsize[i],Mathf.Cos(k * corner) * maxsize[i],h);vs[count + 4] = new Vector3(Mathf.Sin((k + 0.5f) * corner) * minSize[i],Mathf.Cos((k + 0.5f) * corner) * minSize[i],h);vs[count + 5] = new Vector3(Mathf.Sin((k + 0.5f) * corner) * minSize[(i + 1) % 5],Mathf.Cos((k + 0.5f) * corner) * minSize[(i + 1) % 5],l);vs[count + 6] = new Vector3(Mathf.Sin(k * corner) * maxsize[i],Mathf.Cos(k * corner) * maxsize[i],h);vs[count + 7] = new Vector3(Mathf.Sin(k * corner) * maxsize[(i + 1) % 5],Mathf.Cos(k * corner) * maxsize[(i + 1) % 5],l);vs[count + 8] = new Vector3(Mathf.Sin((k - 0.5f) * corner) * minSize[(i + 1) % 5],Mathf.Cos((k - 0.5f) * corner) * minSize[(i + 1) % 5],l);vs[count + 9] = new Vector3(Mathf.Sin(k * corner) * maxsize[i],Mathf.Cos(k * corner) * maxsize[i],h);vs[count + 10] = new Vector3(Mathf.Sin((k - 0.5f) * corner) * minSize[(i + 1) % 5],Mathf.Cos((k - 0.5f) * corner) * minSize[(i + 1) % 5],l);vs[count + 11] = new Vector3(Mathf.Sin((k - 0.5f) * corner) * minSize[i],Mathf.Cos((k - 0.5f) * corner) * minSize[i],h);//确定法线if (sophisticated) {newNormals[count] = Vector3.Normalize(vs[count] - new Vector3(0,0,h));newNormals[count + 1] = Vector3.Normalize(vs[count + 1] - new Vector3(0,0,l));newNormals[count + 2] = Vector3.Normalize(vs[count + 2] - new Vector3(0,0,l));newNormals[count + 3] = Vector3.Normalize(vs[count + 3] - new Vector3(0,0,h));newNormals[count + 4] = Vector3.Normalize(vs[count + 4] - new Vector3(0,0,h));newNormals[count + 5] = Vector3.Normalize(vs[count + 5] - new Vector3(0,0,l));newNormals[count + 6] = Vector3.Normalize(vs[count + 6] - new Vector3(0,0,h));newNormals[count + 7] = Vector3.Normalize(vs[count + 7] - new Vector3(0,0,l));newNormals[count + 8] = Vector3.Normalize(vs[count + 8] - new Vector3(0,0,l));newNormals[count + 9] = Vector3.Normalize(vs[count + 9] - new Vector3(0,0,h));newNormals[count + 10] = Vector3.Normalize(vs[count + 10] - new Vector3(0,0,l));newNormals[count + 11] = Vector3.Normalize(vs[count + 11] - new Vector3(0,0,h));} else {for (int j = 0; j < 4; j++) {Vector3 newNormal = Vector3.Cross(vs[count + 3 * j + 1] - vs[count + 3 * j + 0],vs[count + 3 * j + 2] - vs[count + 3 * j + 0]);for (int z = 0; z < 3; z++) {newNormals[count + 3 * j + z] = Vector3.Normalize(newNormal);}}}count += 12;}}//确定顶点序列for (int i = 0; i < ts.Length; i++) {ts[i] = i;}//创建网格mesh = new Mesh();GetComponent<MeshFilter>().mesh = mesh;mesh.vertices = vs;mesh.uv = newUVs;mesh.triangles = ts;mesh.normals = newNormals;}}

通过调节变量图中几何体均可实现。Mesh编程步骤见 Mesh网格编程（一）。

原文转载：http://blog.csdn.net/qq_18408937/article/details/44181489