Unity3D绘制物体表面三角形网格
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1 仅绘制三角形网格
1）创建游戏对象
创建一个空对象，重命名为 Grid，并在其下添加需要绘制网格的对象，如下：
场景显示如下：
2）添加脚本组件
GridController.cs
using System;
using UnityEngine;
public class GridController : MonoBehaviour
private void Start ()
ForAllChildren(transform, RebuildMesh);
private void RebuildMesh(Transform transform)
MeshFilter meshFilter = transform.GetComponent<MeshFilter>();
if (meshFilter != null && meshFilter.mesh != null)
int[] indices = MakeIndices(meshFilter.mesh.triangles);
meshFilter.mesh.SetIndices(indices, MeshTopology.Lines, 0);
private int[] MakeIndices(int[] triangles)
int[] indices = new int[2 * triangles.Length];
for( int i = 0; i < triangles.Length; i += 3 )
for (int j = 0; j < 6; j++)
// 每个三角形转换为3条线段, 每个顶点使用2次, 对应的顶点序列是: 0, 1, 1, 2, 2, 0, 通式: (j + 1) % 6 / 2, j 的范围: 1 ~ 5
indices[2 * i + j] = triangles[i + (j + 1) % 6 / 2];
return indices;
private void ForAllChildren(Transform transform, Action<Transform> action)
action.Invoke(transform);
for (int i = 0; i < transform.childCount; i++)
ForAllChildren(transform.GetChild(i), action);
说明： GridController 脚本组件挂在 Grid 对象上。
运行效果：
3）给网格添加新材质
GridController.cs
using System;
using UnityEngine;
public class GridController : MonoBehaviour
public Material material;
private void Start ()
ForAllChildren(transform, RebuildMesh);
private void RebuildMesh(Transform transform)
MeshFilter meshFilter = transform.GetComponent<MeshFilter>();
MeshRenderer meshRenderer = transform.GetComponent<MeshRenderer>();
if (meshFilter != null && meshFilter.mesh != null && meshRenderer != null)
meshRenderer.material = material;
int[] indices = MakeIndices(meshFilter.mesh.triangles);
meshFilter.mesh.SetIndices(indices, MeshTopology.Lines, 0);
private int[] MakeIndices(int[] triangles)
int[] indices = new int[2 * triangles.Length];
for( int i = 0; i < triangles.Length; i += 3 )
for (int j = 0; j < 6; j++)
// 每个三角形转换为3条线段, 每个顶点使用2次, 对应的顶点序列是: 0, 1, 1, 2, 2, 0, 通式: (j + 1) % 6 / 2, j 的范围: 1 ~ 5
indices[2 * i + j] = triangles[i + (j + 1) % 6 / 2];
return indices;
private void ForAllChildren(Transform transform, Action<Transform> action)
action.Invoke(transform);
for (int i = 0; i < transform.childCount; i++)
ForAllChildren(transform.GetChild(i), action);
运行效果：
2 绘制表面和三角形网格
场景中所有对象同第 1 节，脚本组件如下：
GridController.cs
using System;
using UnityEngine;
using UnityEngine.Rendering;
public class GridController : MonoBehaviour
public Material material;
private void Start ()
ForAllChildren(transform, RebuildMesh);
private void RebuildMesh(Transform transform)
MeshFilter meshFilter = transform.GetComponent<MeshFilter>();
MeshRenderer meshRenderer = transform.GetComponent<MeshRenderer>();
if (meshFilter != null && meshFilter.mesh != null && meshRenderer != null)
InitMaterials(meshRenderer);
int[] indices = MakeIndices(meshFilter.mesh.triangles);
InitSubMesh(meshFilter.mesh, indices, indices.Length / 3);
private void InitMaterials(MeshRenderer meshRenderer)
Material[] materials = new Material[meshRenderer.materials.Length + 1];
meshRenderer.materials.CopyTo(materials, 0);
materials[materials.Length - 1] = material;
meshRenderer.materials = materials;
private void InitSubMesh(Mesh mesh, int[] indices, int divide)
mesh.SetIndexBufferParams(indices.Length, IndexFormat.UInt32);
mesh.SetIndexBufferData(indices, 0, 0, indices.Length);
mesh.subMeshCount = 2; // 设置2个子网格
// 第一部分绘制三角形内部
SubMeshDescriptor subMeshDescriptor1 = new SubMeshDescriptor(0, divide, MeshTopology.Triangles);
mesh.SetSubMesh(0, subMeshDescriptor1);
// 第二部分绘制线段
SubMeshDescriptor subMeshDescriptor2 = new SubMeshDescriptor(divide, indices.Length - divide, MeshTopology.Lines);
mesh.SetSubMesh(1, subMeshDescriptor2);
private int[] MakeIndices(int[] triangles)
int[] indices = new int[3 * triangles.Length];
triangles.CopyTo(indices, 0);
for( int i = 0; i < triangles.Length; i += 3 )
for (int j = 0; j < 6; j++)
// 每个三角形转换为3条线段, 每个顶点使用2次, 对应的顶点序列是: 0, 1, 1, 2, 2, 0, 通式: (j + 1) % 6 / 2, j 的范围: 1 ~ 5
indices[triangles.Length + 2 * i + j] = triangles[i + (j + 1) % 6 / 2];
return indices;
private void ForAllChildren(Transform transform, Action<Transform> action)
action.Invoke(transform);
for (int i = 0; i < transform.childCount; i++)
ForAllChildren(transform.GetChild(i), action);
运行效果：
Unity - 绘制正五边形网格
本文简述了Unity中绘制正五边形网格的基本方法：计算顶点信息、设置三角形覆盖信息、创建配置mesh
绘制方法
- 基本思路：计算出五边形顶点坐标信息作为数组，设置三角形包围方式，再创建新的mesh配置vertices、triangle参数，最终赋值到当前mesh上
- 项目实现：
- 创建DrawPentagon.cs，挂在于带有mesh的物体上（本例为Quad
- 编写代码如下：
- 查看所创建的mesh信息
public class DrawPentagon : MonoBehaviour
{
private Vector3[] newVertices; //五边形顶点数组
private int[] newTriangles; //五边形网格内的三角形网格信息
void Start()
{
//1. 创建五边形顶点坐标数组：顶点编号0~4
newVertices = new Vector3[5] {
Vector3.zero,
new Vector3(Mathf.Cos(Mathf.Deg2Rad * 36), 0, Mathf.Sin(Mathf.Deg2Rad * 36)),
new Vector3(2 * Mathf.Cos(Mathf.Deg2Rad * 36), 0, 0),
new Vector3(Mathf.Cos(Mathf.Deg2Rad * 72) + 1, 0, -Mathf.Sin(Mathf.Deg2Rad * 72)),
new Vector3(Mathf.Cos(Mathf.Deg2Rad * 72), 0, -Mathf.Sin(Mathf.Deg2Rad * 72))
/*
newVertices[0] = (0.0, 0.0, 0.0)
newVertices[1] = (0.8, 0.0, 0.6)
newVertices[2] = (1.6, 0.0, 0.0)
newVertices[3] = (1.3, 0.0, -1.0)
newVertices[4] = (0.3, 0.0, -1.0)
*/
};
//2. 设根据已有的顶点编号设置三角形包围顺序，例如0,1,2顶点围成一个三角形；0,2,3顶点围成另一三角形
newTriangles = new int[9] { 0, 1, 2, 0, 2, 3, 0, 3, 4 };
//错误情况：三角形数量不足
//newTriangles = new int[6] { 0, 1, 2, 0, 2, 3 };
//错误情况：三角形覆盖面不全
//newTriangles = new int[9] { 0, 1, 2, 1, 2, 3, 0, 3, 4 };
//3. 创建mesh信息：顶点数据、三角形
Mesh mesh = new Mesh
{
name = "Pentagon",
vertices = newVertices,
triangles = newTriangles
};
GetComponent<MeshFilter>().mesh = mesh;
}
}示意图及错误示例：
参考
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