PCL1.8.1 分割 - Plane model

通过平面进行分割，代码中随机生成z=1平面上的点，修改三个点的z！=1，使用平面分割保留z=1上的点。

http://www.pointclouds.org/documentation/tutorials/planar_segmentation.php#planar-segmentation

#include <iostream>
#include <pcl/ModelCoefficients.h>
#include <pcl/io/pcd_io.h>
#include <pcl/point_types.h>
#include <pcl/sample_consensus/method_types.h>
#include <pcl/sample_consensus/model_types.h>
#include <pcl/segmentation/sac_segmentation.h>

int main (int argc, char** argv)
{
  pcl::PointCloud<pcl::PointXYZ>::Ptr cloud(new pcl::PointCloud<pcl::PointXYZ>);

  // Fill in the cloud data
  cloud->width  = 15;
  cloud->height = 1;
  cloud->points.resize (cloud->width * cloud->height);

  // 随机产生z=1的平面点
  for (std::size_t i = 0; i < cloud->points.size (); ++i)
  {
    cloud->points[i].x = 1024 * rand () / (RAND_MAX + 1.0f);
    cloud->points[i].y = 1024 * rand () / (RAND_MAX + 1.0f);
    cloud->points[i].z = 1.0;
  }

  // 设置其中三个点不在z=1平面上
  cloud->points[0].z = 2.0;
  cloud->points[3].z = -2.0;
  cloud->points[6].z = 4.0;

  //创建平面模型 ax+by+cz+d=0
  pcl::ModelCoefficients::Ptr coefficients (new pcl::ModelCoefficients);
  pcl::PointIndices::Ptr inliers (new pcl::PointIndices);
  // Create the segmentation object
  pcl::SACSegmentation<pcl::PointXYZ> seg;
  // Optional
  seg.setOptimizeCoefficients (true);
  // Mandatory
  seg.setModelType (pcl::SACMODEL_PLANE);
  seg.setMethodType (pcl::SAC_RANSAC);
  seg.setDistanceThreshold (0.01);

  seg.setInputCloud (cloud);
  seg.segment (*inliers, *coefficients);

  if (inliers->indices.size () == 0)
  {
    PCL_ERROR ("Could not estimate a planar model for the given dataset.");
    return (-1);
  }

  //[0]:a  [1]:b  [2]:c  [3]:d
  std::cerr << "Model coefficients: " << coefficients->values[0] << " "
                                      << coefficients->values[1] << " "
                                      << coefficients->values[2] << " "
                                      << coefficients->values[3] << std::endl;

  std::cerr << "Model inliers: " << inliers->indices.size () << std::endl;
  for (std::size_t i = 0; i < inliers->indices.size (); ++i)
    std::cerr << inliers->indices[i] << "    " << cloud->points[inliers->indices[i]].x << " "
                                               << cloud->points[inliers->indices[i]].y << " "
                                               << cloud->points[inliers->indices[i]].z << std::endl;

  return (0);
}