我需要一个C++版本的代码,谢谢
时间: 2024-03-19 18:44:52 浏览: 14
好的,下面是一个基于 C++ 的求解三维点集最小包容盒的代码,与前面的 Python 代码思路相似,使用了 Eigen 库来进行矩阵计算:
```c++
#include <iostream>
#include <vector>
#include <Eigen/Core>
#include <Eigen/SVD>
#include <Eigen/Geometry>
Eigen::Vector3d getNormal(const Eigen::Vector3d& p1, const Eigen::Vector3d& p2, const Eigen::Vector3d& p3) {
Eigen::Vector3d e1 = p2 - p1;
Eigen::Vector3d e2 = p3 - p1;
return e1.cross(e2).normalized();
}
void getBoundingBox(const std::vector<Eigen::Vector3d>& points, double& length, double& width, double& height, Eigen::Matrix3d& rotation) {
Eigen::Matrix3Xd points_mat(3, points.size());
for (int i = 0; i < points.size(); i++) {
points_mat.col(i) = points[i];
}
Eigen::Matrix3Xd hull_points_mat;
std::vector<int> hull_indices;
// 计算凸包
Eigen::Matrix3Xd vertices = points_mat.transpose();
Eigen::MatrixXd hull = vertices.transpose().colPivHouseholderQr().solve(Eigen::MatrixXd::Ones(vertices.rows(), 1));
hull_points_mat = vertices * hull;
hull_points_mat.transposeInPlace();
// 计算法向量
Eigen::Vector3d normal = getNormal(hull_points_mat.col(0), hull_points_mat.col(1), hull_points_mat.col(2));
// 计算最小包容盒的边界
double c = hull_points_mat.col(0).dot(normal);
double min_x = points_mat.row(0).minCoeff(), max_x = points_mat.row(0).maxCoeff();
double min_y = points_mat.row(1).minCoeff(), max_y = points_mat.row(1).maxCoeff();
double min_z = points_mat.row(2).minCoeff(), max_z = points_mat.row(2).maxCoeff();
Eigen::Matrix<double, 3, 8> corners;
corners << min_x, min_x, max_x, max_x, min_x, min_x, max_x, max_x,
min_y, max_y, max_y, min_y, min_y, max_y, max_y, min_y,
(c - normal(0) * min_x - normal(1) * min_y) / normal(2),
(c - normal(0) * min_x - normal(1) * max_y) / normal(2),
(c - normal(0) * max_x - normal(1) * max_y) / normal(2),
(c - normal(0) * max_x - normal(1) * min_y) / normal(2),
min_z, min_z, min_z, min_z,
max_z, max_z, max_z, max_z;
// 计算包容盒中心和旋转矩阵
Eigen::Vector3d centroid = corners.rowwise().mean();
corners.colwise() -= centroid;
Eigen::JacobiSVD<Eigen::Matrix3d> svd(corners, Eigen::ComputeFullV);
Eigen::Matrix3d rotation_matrix = svd.matrixV().col(0) * svd.matrixV().col(1).transpose();
if (rotation_matrix.determinant() < 0) {
rotation_matrix.col(2) *= -1;
}
length = (corners.row(0).maxCoeff() - corners.row(0).minCoeff()) / 2.0;
width = (corners.row(1).maxCoeff() - corners.row(1).minCoeff()) / 2.0;
height = (corners.row(2).maxCoeff() - corners.row(2).minCoeff()) / 2.0;
rotation = rotation_matrix;
}
int main() {
std::vector<Eigen::Vector3d> points {
{0, 0, 0},
{1, 0, 0},
{0, 1, 0},
{0, 0, 1},
{1, 1, 1},
{1, 1, 0},
{1, 0, 1},
{0, 1, 1}
};
double length, width, height;
Eigen::Matrix3d rotation;
getBoundingBox(points, length, width, height, rotation);
std::cout << "Length: " << length << ", Width: " << width << ", Height: " << height << std::endl;
std::cout << "Rotation Matrix: \n" << rotation << std::endl;
return 0;
}
```
你可以传入一个 `std::vector<Eigen::Vector3d>` 类型的点集作为参数,函数将返回最小包容盒的长度、宽度、高度以及旋转矩阵,其中旋转矩阵是一个 3x3 的矩阵,表示将包容盒沿着 X、Y、Z 轴旋转的角度。这里使用 Eigen 库来进行矩阵计算,如果你没有安装 Eigen 库,可以通过以下命令进行安装:
```
sudo apt-get install libeigen3-dev
```