生成球 使用openMesh 库

Posted 2022-03-15 eat-too-much

简介

使用openmesh生成一个球，采用的是标准球坐标系。

// 生成球  n 最好输入偶数  10 或者 100 
#include <iostream>
#include <OpenMesh/Core/IO/MeshIO.hh>
#include <OpenMesh/Core/Mesh/TriMesh_ArrayKernelT.hh>
#include<cmath>
#define pi 3.1415926
using namespace std;
typedef OpenMesh::TriMesh_ArrayKernelT<> MyMesh;

int main()

    MyMesh mesh;
    int n,count=10000,k=-1;
    cout << "n:";
    cin >> n;
    MyMesh::VertexHandle *vhandle = new MyMesh::VertexHandle[count];
    std::vector<MyMesh::VertexHandle>face_vhandles;
    for (int j =0;j < n;j++) 
        double distance = cos(j*pi / n);// 原先是 sin
        double r_circle = sin(j*pi / n);
        for (int i = 0;i < n;i++) 
            ++k;
            vhandle[k]=mesh.add_vertex(MyMesh::Point(r_circle*cos(2 * i*pi / n), r_circle*sin(2 * i*pi / n), distance));
            // 对网格添加顶点
        
    
    for (int i = 0;i < n-1;i++) 
        for (int j = 0;j < n;j++) 
            int topRight = i * n + j;
            int topLeft = i * n + (j + 1) % n;
            int bottomRight = (i + 1)*n + j;
            int bottomLeft = (i + 1)*n + (j + 1) % n;
            face_vhandles.clear();
            face_vhandles.push_back(vhandle[bottomRight]);
            face_vhandles.push_back(vhandle[bottomLeft]);
            face_vhandles.push_back(vhandle[topRight]);
            mesh.add_face(face_vhandles);

            face_vhandles.clear();
            face_vhandles.push_back(vhandle[bottomLeft]);
            face_vhandles.push_back(vhandle[topLeft]);
            face_vhandles.push_back(vhandle[topRight]);
            mesh.add_face(face_vhandles);

        
    
    //vhandle[k+1] = mesh.add_vertex(MyMesh::Point(0, 0, 1));
    vhandle[k+1] = mesh.add_vertex(MyMesh::Point(0, 0, -1));
    for (int i = 0;i < n;i++) 
        //face_vhandles.clear();
        //
        //
        //face_vhandles.push_back(vhandle[i]);
        //face_vhandles.push_back(vhandle[(i + 1) % n]);
        //face_vhandles.push_back(vhandle[k + 2]);
        //mesh.add_face(face_vhandles);

        face_vhandles.clear();
        
        
        face_vhandles.push_back(vhandle[k- i]);
        face_vhandles.push_back(vhandle[k - (i + 1) % n]);
        face_vhandles.push_back(vhandle[k + 1]);
        mesh.add_face(face_vhandles);
    
    try
    
        if (!OpenMesh::IO::write_mesh(mesh, "output5 .off")) 
            std::cerr << "Cannot write mesh to file ' output5 .off ' " << std::endl;
            return 1;
        
    
    catch (std::exception&x) 
        std::cerr << x.what() << std::endl;
        return 1;
    
    return 0;