即三角网格插值细分
http://graphics.stanford.edu/courses/cs468-10-fall/LectureSlides/10_Subdivision.pdf
w 采用1/16.
bug 调了很久,就是 一条半边对应面的方向其实不太稳定。
#pragma once #pragma once #include "strategy.h" #include "qwidget.h" #include <OpenMesh/Core/Mesh/PolyMesh_ArrayKernelT.hh> #include <OpenMesh/Core/IO/MeshIO.hh> #include <map> class Butterfly :public Strategy, public QWidget { Q_OBJECT private: typedef OpenMesh::PolyMesh_ArrayKernelT<> MyMesh; MyMesh mesh; std::map<int, OpenMesh::Vec3d> facePoints; std::map<int, OpenMesh::Vec3d> edgePoints; std::map<int, OpenMesh::Vec3d> vertexPoints; int times; const double w = 1.0 / 16.0; public: Butterfly(Data* data_); ~Butterfly(); void genCube(); void genFacePoint(); void genEdgePoint(); void genVertexPoint(); void connectPoints(); void genMesh(std::string name); bool Run(); void getResult(); };
#include "butterfly_surface_subdivision.h" #include <iostream> #include <unordered_map> #include <QInputDialog> /** * @description: 构造函数 * @param {type} * @return {type} */ Butterfly::Butterfly(Data* data_) : Strategy(data_) { times = 1; genCube(); } /** * @description: 析构函数 * @param {type} * @return {type} */ Butterfly::~Butterfly() {} /** * @description: 一整套流程 * @param {type} * @return {int} 管线运行是否成功 */ bool Butterfly::Run() { times = QInputDialog::getInt(this, "Surface Mesh", "Please input times", 1, 1, 1000, 1); for (int i = 0; i <= times; i++) { if (i == 0) { char a[20]; sprintf(a, "output%d.off", i); genMesh(a); } else { genEdgePoint(); genVertexPoint(); connectPoints(); char a[20]; sprintf(a, "output%d.off", i); genMesh(a); } // 清空变量 std::cout << "[DEBUG] 迭代了第 " << i << " 次。" << std::endl; } getResult(); return true; } /** * @description: 生成一个立方体(四边形网格) * @param {type} * @return {type} */ void Butterfly::genCube() { if (getData()->triMesh.n_vertices() != 0) { for (auto it : getData()->triMesh.vertices()) { mesh.add_vertex(getData()->triMesh.point(it)); } for (auto it : getData()->triMesh.faces()) { std::vector<MyMesh::VertexHandle> face_vhandles; for (auto iit : it.vertices()) { face_vhandles.push_back(iit); } mesh.add_face(face_vhandles); } return; } MyMesh::VertexHandle vhandle[9]; vhandle[0] = mesh.add_vertex(MyMesh::Point(-1, -1, 1)); vhandle[1] = mesh.add_vertex(MyMesh::Point(1, -1, 1)); vhandle[2] = mesh.add_vertex(MyMesh::Point(1, 1, 1)); vhandle[3] = mesh.add_vertex(MyMesh::Point(-1, 1, 1)); vhandle[4] = mesh.add_vertex(MyMesh::Point(-1, -1, -1)); vhandle[5] = mesh.add_vertex(MyMesh::Point(1, -1, -1)); vhandle[6] = mesh.add_vertex(MyMesh::Point(1, 1, -1)); vhandle[7] = mesh.add_vertex(MyMesh::Point(-1, 1, -1)); std::vector<MyMesh::VertexHandle> face_vhandles; face_vhandles.push_back(vhandle[0]); face_vhandles.push_back(vhandle[1]); face_vhandles.push_back(vhandle[2]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(vhandle[0]); face_vhandles.push_back(vhandle[2]); face_vhandles.push_back(vhandle[3]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(vhandle[7]); face_vhandles.push_back(vhandle[6]); face_vhandles.push_back(vhandle[5]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(vhandle[7]); face_vhandles.push_back(vhandle[5]); face_vhandles.push_back(vhandle[4]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(vhandle[1]); face_vhandles.push_back(vhandle[0]); face_vhandles.push_back(vhandle[4]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(vhandle[1]); face_vhandles.push_back(vhandle[4]); face_vhandles.push_back(vhandle[5]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(vhandle[2]); face_vhandles.push_back(vhandle[1]); face_vhandles.push_back(vhandle[5]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(vhandle[2]); face_vhandles.push_back(vhandle[5]); face_vhandles.push_back(vhandle[6]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(vhandle[3]); face_vhandles.push_back(vhandle[2]); face_vhandles.push_back(vhandle[6]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(vhandle[3]); face_vhandles.push_back(vhandle[6]); face_vhandles.push_back(vhandle[7]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(vhandle[0]); face_vhandles.push_back(vhandle[3]); face_vhandles.push_back(vhandle[7]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(vhandle[0]); face_vhandles.push_back(vhandle[7]); face_vhandles.push_back(vhandle[4]); mesh.add_face(face_vhandles); } /** * @description: 考虑边上和内部 * @param {type} * @return {type} */ void Butterfly::genEdgePoint() { edgePoints.clear(); for (auto e_it = mesh.edges_begin(); e_it != mesh.edges_end(); ++e_it) { // 得到边所代表的半边 OpenMesh::HalfedgeHandle heh1 = mesh.halfedge_handle(*e_it, 0); // 默认一个方向的半边 OpenMesh::Vec3d edgePoint(0, 0, 0); int edgePointsNumber = 0; OpenMesh::DefaultTraits::Point pointV = mesh.point(mesh.from_vertex_handle(heh1)); // 这条(半)边的起点 OpenMesh::DefaultTraits::Point pointW = mesh.point(mesh.to_vertex_handle(heh1)); // 这条(半)边的终点 OpenMesh::FaceHandle fh1 = mesh.face_handle(heh1); OpenMesh::HalfedgeHandle heh = mesh.opposite_halfedge_handle(heh1); OpenMesh::FaceHandle fh2 = mesh.face_handle(heh); std::vector<OpenMesh::VertexHandle> ss1; // d3 d4 std::vector<OpenMesh::VertexHandle> ss2; // d5 d6 d7 d8 std::vector<OpenMesh::VertexHandle> ss_all; // 得到这两个面的所有顶点 for (auto fv_it : mesh.fv_range(fh1)) { if (fv_it.idx() != mesh.from_vertex_handle(heh1).idx() && fv_it.idx() != mesh.to_vertex_handle(heh1).idx()) ss1.push_back(fv_it); } for (auto fv_it : mesh.fv_range(fh2)) { if (fv_it.idx() != mesh.from_vertex_handle(heh1).idx() && fv_it.idx() != mesh.to_vertex_handle(heh1).idx()) ss1.push_back(fv_it); } if (ss1.size() != 2) { std::cout << "[ERROR] " << ss1.size() << std::endl; } ss_all.assign(ss1.begin(), ss1.end()); ss_all.push_back(mesh.from_vertex_handle(heh1)); ss_all.push_back(mesh.to_vertex_handle(heh1)); for (const auto& fe : mesh.fe_range(fh1)) { OpenMesh::HalfedgeHandle fe_heh1 = mesh.halfedge_handle(fe, 0); //OpenMesh::FaceHandle fe_fh1 = mesh.face_handle(fe_heh1); OpenMesh::HalfedgeHandle fe_heh = mesh.opposite_halfedge_handle(fe_heh1); OpenMesh::FaceHandle fe_fh2 = mesh.face_handle(fe_heh); if (fe_fh2 == fh1 || fe_fh2 == fh2) { OpenMesh::FaceHandle fe_fh1 = mesh.face_handle(fe_heh1); if (fe_fh1 == fh1 || fe_fh1 == fh2) continue; for (const auto& ffv : mesh.fv_range(fe_fh1)) { if (std::find(ss_all.begin(), ss_all.end(), ffv) == ss_all.end()) { ss2.push_back(ffv); } } } else { for (const auto& ffv : mesh.fv_range(fe_fh2)) { if (std::find(ss_all.begin(), ss_all.end(), ffv) == ss_all.end()) { ss2.push_back(ffv); } } } } //std::cout << "=1=\n"; //for (const auto& ffv : mesh.fv_range(fh1)) { // std::cout << mesh.point(ffv)[0] << " " << mesh.point(ffv)[1] << " " << mesh.point(ffv)[2] << "\n"; //} //for (const auto& ffv : mesh.fv_range(fh2)) { // std::cout << mesh.point(ffv)[0] << " " << mesh.point(ffv)[1] << " " << mesh.point(ffv)[2] << "\n"; //} //std::cout << mesh.point(ss_all[0])[0] << " " << mesh.point(ss_all[0])[1] << " " << mesh.point(ss_all[0])[2] << "\n"; //std::cout << mesh.point(ss_all[1])[0] << " " << mesh.point(ss_all[1])[1] << " " << mesh.point(ss_all[1])[2] << "\n"; //std::cout << mesh.point(ss_all[2])[0] << " " << mesh.point(ss_all[2])[1] << " " << mesh.point(ss_all[2])[2] << "\n"; //std::cout << mesh.point(ss_all[3])[0] << " " << mesh.point(ss_all[3])[1] << " " << mesh.point(ss_all[3])[2] << "\n"; //std::cout << "==\n"; for (const auto& fe : mesh.fe_range(fh2)) { OpenMesh::HalfedgeHandle fe_heh1 = mesh.halfedge_handle(fe, 0); //OpenMesh::FaceHandle fe_fh1 = mesh.face_handle(fe_heh1); OpenMesh::HalfedgeHandle fe_heh = mesh.opposite_halfedge_handle(fe_heh1); OpenMesh::FaceHandle fe_fh2 = mesh.face_handle(fe_heh); if (fe_fh2 == fh1 || fe_fh2 == fh2) { OpenMesh::FaceHandle fe_fh1 = mesh.face_handle(fe_heh1); if (fe_fh1 == fh1 || fe_fh1 == fh2) continue; for (const auto& ffv : mesh.fv_range(fe_fh1)) { if (std::find(ss_all.begin(), ss_all.end(), ffv) == ss_all.end()) { ss2.push_back(ffv); } } } else { for (const auto& ffv : mesh.fv_range(fe_fh2)) { if (std::find(ss_all.begin(), ss_all.end(), ffv) == ss_all.end()) { ss2.push_back(ffv); } } } } if (ss2.size() != 4) { std::cout << "[ERROR] " << ss2.size() << std::endl; } edgePoints[heh1.idx()] = 1.0 / 2.0 * (pointV + pointW) + w * (mesh.point(ss1[0]) + mesh.point(ss1[1])) -w/2.0 *(mesh.point(ss2[0]) + mesh.point(ss2[1]) + mesh.point(ss2[2]) + mesh.point(ss2[3])); } } /** * @description: 生成新的顶点 * @param {type} * @return {type} */ void Butterfly::genVertexPoint() { vertexPoints.clear(); // 原始点接触的面的所有的面点的均值 for (auto v_it = mesh.vertices_begin(); v_it != mesh.vertices_end(); v_it++) { if (mesh.is_boundary(v_it)) { // 如果这个顶点处于边界 OpenMesh::Vec3d point(0, 0, 0); for (auto vv_it = mesh.vv_begin(v_it); vv_it.is_valid(); vv_it++) { if (mesh.is_boundary(vv_it)) { point += mesh.point(vv_it); } } vertexPoints[(*v_it).idx()] = 3.0 / 4.0 * mesh.point(v_it) + 1.0 / 8.0 * (point); } else { // 计算度 n, 度 int n = 0; for (auto vf_it = mesh.vv_begin(v_it); vf_it.is_valid(); ++vf_it) { n++; } // 计算β double beta = 1.0 / n * (5.0 / 8.0 - pow(3.0 / 8.0 + 1.0 / 4.0 * cos(2 * M_PI / n), 2)); // 下面的需要么?? if (n < 3) beta = 3.0 / 16.0; OpenMesh::Vec3d point(0, 0, 0); for (auto vv_it = mesh.vv_begin(v_it); vv_it.is_valid(); ++vv_it) { point += beta * mesh.point(vv_it); } vertexPoints[(*v_it).idx()] = (1 - n * beta) * mesh.point(v_it) + point; } } } /** * @description: 连接面点和边点 * @param {type} * @return {type} */ void Butterfly::connectPoints() { if (!mesh.has_vertex_status()) mesh.request_vertex_status(); if (!mesh.has_face_status()) mesh.request_face_status(); if (!mesh.has_edge_status()) mesh.request_edge_status(); // 先将旧顶点移动到新顶点 std::unordered_map<int, OpenMesh::VertexHandle> vertexHandle; for (auto v_it = mesh.vertices_begin(); v_it != mesh.vertices_end(); v_it++) { //mesh.set_point(*v_it, (OpenMesh::DefaultTraits::Point)vertexPoints[(*v_it).idx()]); vertexHandle[(*v_it).idx()] = *v_it; } std::vector<MyMesh::VertexHandle> facePointsHandle; std::vector<MyMesh::FaceHandle> faceHandle; std::unordered_map<int, MyMesh::VertexHandle> edgesHandle; // 再加入所有的要加入的边点 for (const auto& eh : mesh.edges()) { edgesHandle[mesh.halfedge_handle(eh, 0).idx()] = mesh.add_vertex(MyMesh::Point(edgePoints[mesh.halfedge_handle(eh, 0).idx()])); } for (const auto& fh : mesh.faces()) { faceHandle.push_back(fh); } std::vector<std::vector<MyMesh::VertexHandle>> v; for (const auto& fh : mesh.faces()) { std::vector<MyMesh::VertexHandle> handlerVector(6); int pointsNumber = 0; for (const auto& fvh : mesh.fv_range(fh)) { handlerVector[pointsNumber] = vertexHandle[fvh.idx()]; pointsNumber++; } for (const auto& feh : mesh.fe_range(fh)) { auto fehh = mesh.halfedge_handle(feh, 0); handlerVector[pointsNumber] = edgesHandle[fehh.idx()]; pointsNumber++; } v.push_back(handlerVector); } for (int i = 0; i < v.size(); i++) { mesh.delete_face(faceHandle[i], true); std::vector<MyMesh::VertexHandle> handlerVector; for (int j = 0; j < v[i].size(); j++) { handlerVector.push_back(v[i][j]); } std::vector<MyMesh::VertexHandle> face_vhandles; face_vhandles.push_back(handlerVector[3]); face_vhandles.push_back(handlerVector[0]); face_vhandles.push_back(handlerVector[4]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(handlerVector[4]); face_vhandles.push_back(handlerVector[1]); face_vhandles.push_back(handlerVector[5]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(handlerVector[3]); face_vhandles.push_back(handlerVector[4]); face_vhandles.push_back(handlerVector[5]); mesh.add_face(face_vhandles); face_vhandles.clear(); face_vhandles.push_back(handlerVector[2]); face_vhandles.push_back(handlerVector[3]); face_vhandles.push_back(handlerVector[5]); mesh.add_face(face_vhandles); face_vhandles.clear(); } mesh.garbage_collection(); if (mesh.has_vertex_status()) mesh.release_vertex_status(); if (mesh.has_face_status()) mesh.release_face_status(); if (mesh.has_edge_status()) mesh.release_edge_status(); } /** * @description: 输出新网格 * @param {string} name 文件名称 默认 output.obj * @return {type} */ void Butterfly::genMesh(std::string name) { if (name == "") { name = "output.off"; } try { if (!OpenMesh::IO::write_mesh(mesh, name)) { std::cerr << "Cannot write mesh to file 'output.off'" << std::endl; return; } } catch (std::exception& e) { std::cerr << e.what() << std::endl; return; } } void Butterfly::getResult() { //if (getData()->edges.size() == 0) { // getData()->edges.push_back(std::vector<V3f>()); //} getData()->edges.clear(); getData()->edges.push_back(std::vector<V3f>()); for (auto e_it = mesh.edges_begin(); e_it != mesh.edges_end(); ++e_it) { // 得到边所代表的半边 OpenMesh::HalfedgeHandle heh1 = mesh.halfedge_handle(*e_it, 0); // 默认一个方向的半边 OpenMesh::Vec3d edgePoint(0, 0, 0); int edgePointsNumber = 0; OpenMesh::DefaultTraits::Point pointV = mesh.point(mesh.from_vertex_handle(heh1)); // 这条(半)边的起点 OpenMesh::DefaultTraits::Point pointW = mesh.point(mesh.to_vertex_handle(heh1)); // 这条(半)边的终点 getData()->edges[0].push_back({ pointV[0], pointV[1], pointV[2] }); getData()->edges[0].push_back({ pointW[0], pointW[1], pointW[2] }); } }