包围体(包容盒)是一个简单的几何空间,里面包含着复杂形状的物体。为物体添加包围体的目的是快速的进行碰撞检测或者进行精确的碰撞检测之前进行过滤(即当包围体碰撞,才进行精确碰撞检测和处理)。包围体类型包括球体、轴对齐包围盒(AABB)、有向包围盒(OBB)、8-DOP以及凸壳(CONVEX HULL)。
常见包容盒( Bounding Volumes)分类:
如上图所示,,越靠右,包容效果好、越紧密。但是检测速度更慢,也更消耗内存资源。
#include
#include
#include
#include
#include
#include
using namespace std::chrono_literals;
int main(int argc, char** argv)
{
pcl::PointCloud::Ptr cloud(new pcl::PointCloud);
// 从文件读取点云图
pcl::PCDReader reader;
reader.read("G:/vsdata/PCLlearn/PCDdata/bun0.pcd", *cloud);
// 创建惯性矩估算对象,设置输入点云,并进行计算
pcl::MomentOfInertiaEstimation feature_extractor;
feature_extractor.setInputCloud(cloud);
feature_extractor.compute();
std::vector moment_of_inertia;
std::vector eccentricity;
pcl::PointXYZ min_point_AABB;
pcl::PointXYZ max_point_AABB;
pcl::PointXYZ min_point_OBB;
pcl::PointXYZ max_point_OBB;
pcl::PointXYZ position_OBB;
Eigen::Matrix3f rotational_matrix_OBB;
float major_value, middle_value, minor_value;
Eigen::Vector3f major_vector, middle_vector, minor_vector;
Eigen::Vector3f mass_center;
// 获取惯性矩
feature_extractor.getMomentOfInertia(moment_of_inertia);
// 获取离心率
feature_extractor.getEccentricity(eccentricity);
// 获取AABB盒子
feature_extractor.getAABB(min_point_AABB, max_point_AABB);
// 获取OBB盒子
feature_extractor.getOBB(min_point_OBB, max_point_OBB, position_OBB, rotational_matrix_OBB);
feature_extractor.getEigenValues(major_value, middle_value, minor_value);
// 获取主轴major_vector,中轴middle_vector,辅助轴minor_vector
feature_extractor.getEigenVectors(major_vector, middle_vector, minor_vector);
// 获取质心
feature_extractor.getMassCenter(mass_center);
pcl::visualization::PCLVisualizer::Ptr viewer(new pcl::visualization::PCLVisualizer("3D Viewer"));
viewer->setBackgroundColor(0, 0, 0);
viewer->addCoordinateSystem(1.0);
viewer->initCameraParameters();
viewer->addPointCloud(cloud, "sample cloud");
// 添加AABB包容盒
viewer->addCube(min_point_AABB.x, max_point_AABB.x, min_point_AABB.y, max_point_AABB.y, min_point_AABB.z, max_point_AABB.z, 1.0, 1.0, 0.0, "AABB");
viewer->setShapeRenderingProperties(pcl::visualization::PCL_VISUALIZER_REPRESENTATION, pcl::visualization::PCL_VISUALIZER_REPRESENTATION_WIREFRAME, "AABB");
// 添加OBB包容盒
Eigen::Vector3f position(position_OBB.x, position_OBB.y, position_OBB.z);
Eigen::Quaternionf quat(rotational_matrix_OBB);
// position:中心位置
// quat:旋转矩阵
// max_point_OBB.x - min_point_OBB.x 宽度
// max_point_OBB.y - min_point_OBB.y 高度
// max_point_OBB.z - min_point_OBB.z 深度
viewer->addCube(position, quat, max_point_OBB.x - min_point_OBB.x, max_point_OBB.y - min_point_OBB.y, max_point_OBB.z - min_point_OBB.z, "OBB");
viewer->setShapeRenderingProperties(pcl::visualization::PCL_VISUALIZER_REPRESENTATION, pcl::visualization::PCL_VISUALIZER_REPRESENTATION_WIREFRAME, "OBB");
pcl::PointXYZ center(mass_center(0), mass_center(1), mass_center(2));
pcl::PointXYZ x_axis(major_vector(0) + mass_center(0), major_vector(1) + mass_center(1), major_vector(2) + mass_center(2));
pcl::PointXYZ y_axis(middle_vector(0) + mass_center(0), middle_vector(1) + mass_center(1), middle_vector(2) + mass_center(2));
pcl::PointXYZ z_axis(minor_vector(0) + mass_center(0), minor_vector(1) + mass_center(1), minor_vector(2) + mass_center(2));
viewer->addLine(center, x_axis, 1.0f, 0.0f, 0.0f, "major eigen vector");
viewer->addLine(center, y_axis, 0.0f, 1.0f, 0.0f, "middle eigen vector");
viewer->addLine(center, z_axis, 0.0f, 0.0f, 1.0f, "minor eigen vector");
while (!viewer->wasStopped())
{
viewer->spinOnce(10);
std::this_thread::sleep_for(10ms);
}
return (0);
}
实现效果