我很容易细分两个参数化3D表面(两个凸面)。
这是两个镶嵌细分的参数曲面:
现在,我的目的是将两者结合在一起。但是我得到了这个:
我使用Qhull来创建Delaunay三角剖分,它似乎适用于第一个凸面,但不适用于背面。 :(
这是我目前的代码(部分取自ZivS)
#include "Qhull.h"
using namespace orgQhull;
void myQhull::Qhull::runQhull3D(const pcl::PCLPointCloud2& pointCloud, const char* args)
{
std::cout << "runQhull vertices" << std::endl;
numVertices = 0;
std::stringstream verticesSS;
m_externalPoints = new PointCoordinates(3,""); //3 = dimension
pcl::PointCloud<pcl::PointXYZ>::Ptr cloud(new pcl::PointCloud<pcl::PointXYZ>);
pcl::fromPCLPointCloud2(pointCloud, *cloud);
std::vector<double> allPoints;
for (unsigned int i = 0; i < cloud->size(); i++) {
allPoints.push_back(cloud->at(i).x);
allPoints.push_back(cloud->at(i).y);
allPoints.push_back(cloud->at(i).z);
verticesSS << cloud->at(i).x << " " << cloud->at(i).y << " " << cloud->at(i).z << "\n";
numVertices++;
}
vertices += verticesSS.str();
m_externalPoints->append(allPoints); //convert to vector<double>
runQhull(*m_externalPoints, args);
}
void myQhull::Qhull::runQhull(const PointCoordinates &points, const char *qhullCommand2)
{
std::string triangles;
std::stringstream ss;
numSimplices = 0;
int numFaces = 0;
std::cout << numVertices << std::endl;
std::cout << "runQhull facets" << std::endl;
orgQhull::Qhull qHull(points.comment().c_str(), points.dimension(), points.count(), &*points.coordinates(), qhullCommand2);
QhullFacetList facets = qHull.facetList();
for (QhullFacetList::iterator it = facets.begin(); it != facets.end(); ++it)
{
if (!(*it).isGood()) continue;
QhullFacet f = *it;
QhullVertexSet vSet = f.vertices();
auto coord = f.hyperplane().coordinates();
numFaces = vSet.size();
ss << numFaces;
for (QhullVertexSet::iterator vIt = vSet.begin(); vIt != vSet.end(); ++vIt)
{
QhullVertex v = *vIt;
QhullPoint p = v.point();
double * coords = p.coordinates();
ss << " " << p.id() << " ";
}
ss << "\n";
numSimplices++;
}
simplices += ss.str();
std::cout << numSimplices << std::endl;
}
void myQhull::Qhull::saveOff(std::string file)
{
std::cout << "Saving qhull.off" << std::endl;
std::ofstream offFile;
offFile.open(file);
offFile << "OFF\n";
offFile << numVertices << " " << numSimplices << " 0";
offFile << vertices;
offFile << simplices;
offFile.close();
}
void myQhull::Qhull::run(const pcl::PCLPointCloud2& pointCloud)
{
Qhull qhull;
qhull.runQhull3D(pointCloud, "Qt");
qhull.saveOff("qhull.off");
}
另外,我使用了OpenCV的greedy_projection
但没有任何成功。它只能在不加入它们的情况下执行两个曲面细分。
知道为什么会这样吗?
答案 0 :(得分:0)
最后我找到了解决方案。
将“d”添加到qhull.runQhull3D(pointCloud, "d Qt")
会为上下表面生成正确的Delaunay三角剖分。
因此,因为它们是常规网格I,所以手动创建从两个表面连接顶点的边。
谢谢。