VoxelGrid滤波器对点云降采样，并使用PCLVisulizer进行显示

#include <iostream>
#include <pcl/io/pcd_io.h>
#include <pcl/point_types.h>
#include <pcl/filters/voxel_grid.h>
#include <pcl/io/io.h>
#include <pcl/visualization/cloud_viewer.h>
#include <boost/thread/thread.hpp>


int user_data;
void
viewerOneOff(pcl::visualization::PCLVisualizer& viewer)
{
viewer.setBackgroundColor(1.0, 0.5, 1.0);
pcl::PointXYZ o;
o.x = 1.0;
o.y = 0;
o.z = 0;
viewer.addSphere(o, 0.25, "sphere", 0);
std::cout << "i only run once" << std::endl;


}


void
viewerPsycho(pcl::visualization::PCLVisualizer& viewer)
{
static unsigned count = 0;
std::stringstream ss;
ss << "Once per viewer loop: " << count++;
viewer.removeShape("text", 0);
viewer.addText(ss.str(), 200, 300, "text", 0);
//FIXME: possible race condition here:
user_data++;
}
int
main(int argc, char** argv)
{


pcl::PointCloud<pcl::PointXYZI>::Ptr cloud(new pcl::PointCloud<pcl::PointXYZI>);
pcl::PointCloud<pcl::PointXYZI>::Ptr cloud_filtered(new pcl::PointCloud<pcl::PointXYZI>);
// 填入点云数据
pcl::io::loadPCDFile("table_scene_lms400.pcd", *cloud);


// 创建滤波器对象
pcl::VoxelGrid<pcl::PointXYZI> sor;
sor.setInputCloud(cloud);
sor.setLeafSize(0.01f, 0.01f, 0.01f);
sor.filter(*cloud_filtered);
std::cerr << "PointCloud after filtering: " << cloud_filtered->width * cloud_filtered->height
<< " data points (" << pcl::getFieldsList(*cloud_filtered) << ").";




pcl::visualization::PCLVisualizer viewer("PCLVisualizer");
viewer.initCameraParameters();


int v1(0);
viewer.createViewPort(0.0, 0.0, 0.5, 1.0, v1);
viewer.setBackgroundColor(1.0, 0.5, 1.0,v1);
viewer.addText("Cloud before voxelgrid filtering", 10, 10,"v1 test", v1);
pcl::visualization::PointCloudColorHandlerGenericField<pcl::PointXYZI> cloud_color(cloud, "intensity");
viewer.addPointCloud<pcl::PointXYZI>(cloud, cloud_color, "cloud", v1);


int v2(0);
viewer.createViewPort(0.5, 0.0, 1.0, 1.0, v2);
viewer.setBackgroundColor(1.0, 0.5, 1.0,v2);
viewer.addText("Cloud after voxelgrid filtering", 10, 10, "v2 test", v2);
pcl::visualization::PointCloudColorHandlerGenericField<pcl::PointXYZI> cloud_afterfilter_color(cloud_filtered, "intensity");
viewer.addPointCloud<pcl::PointXYZI>(cloud_filtered, cloud_afterfilter_color, "cloud_filtered", v2);


viewer.setPointCloudRenderingProperties(pcl::visualization::PCL_VISUALIZER_POINT_SIZE, 3, "cloud");
viewer.setPointCloudRenderingProperties(pcl::visualization::PCL_VISUALIZER_POINT_SIZE, 3, "cloud_filtered");



while (!viewer.wasStopped())
{
//在此处可以添加其他处理
user_data++;
viewer.spinOnce(100);
boost::this_thread::sleep(boost::posix_time::microseconds(100000));
}






return (0);
}