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#include <liblas/liblas.hpp>
#include <iomanip>
#include <iostream>
#include <sstream>
#include <cmath>
#include <pcl/point_cloud.h>
#include <pcl/io/pcd_io.h>
#include <pcl/point_types.h>
#include <pcl/visualization/pcl_visualizer.h>

//  实现Unshort转为Unchar类型
//int Unshort2Unchar(uint16_t &green, uint8_t &g)
//{
// unsigned short * word;
// word = &green;
// int size = WideCharToMultiByte(CP_ACP, 0, LPCWSTR(word), -1, NULL, 0, NULL, FALSE);
// char *AsciiBuff=new char[size];
// WideCharToMultiByte(CP_ACP, 0, LPCWSTR(word), -1, AsciiBuff, size, NULL, FALSE);
// g = *AsciiBuff;
//
// delete[] AsciiBuff;
// AsciiBuff = NULL;
// return 0;
//}

void writePointCloudFromLas(const char* strInputLasName, const char* strOutPutPointCloudName)
{
 //打开las文件
 std::ifstream ifs;
 ifs.open(strInputLasName, std::ios::in | std::ios::binary);
 if (!ifs.is_open())
 {
  std::cout << “无法打开.las” << std::endl;
  return;
 }
 liblas::ReaderFactory readerFactory;
 liblas::Reader reader = readerFactory.CreateWithStream(ifs);
 //写点云
 pcl::PointCloud<pcl::PointXYZRGBA>::Ptr cloudOutput(new pcl::PointCloud<pcl::PointXYZRGBA>());
 cloudOutput->clear();
 while (reader.ReadNextPoint())
 {
  double x = reader.GetPoint().GetX();
  double y = reader.GetPoint().GetY();
  double z = reader.GetPoint().GetZ();
  uint16_t red = reader.GetPoint().GetColor()[0];
  uint16_t green = reader.GetPoint().GetColor()[1];
  uint16_t blue = reader.GetPoint().GetColor()[2];
  
  /*****颜色说明
  *   uint16_t  范围为0-256*256 ；
  *   pcl 中 R  G  B利用的unsigned char  0-256； 
  *   因此这里将uint16_t 除以256  得到  三位数的0-256的值 
  *   从而进行rgba 值32位 的位运算。
  *
  ******/

  pcl::PointXYZRGBA thePt;  //int rgba = 255<<24 | ((int)r) << 16 | ((int)g) << 8 | ((int)b);
  thePt.x = x; thePt.y = y; thePt.z = z;
  thePt.rgba = (uint32_t)255 << 24 | (uint32_t)(red / 256) << 16 | (uint32_t)(green / 256) << 8 | (uint32_t)(blue / 256);
      //uint32_t rgb = *reinterpret_cast<int*>(&thePt.rgb);  //reinterpret_cast 强制转换
  cloudOutput->push_back(thePt);
 }

 boost::shared_ptr<pcl::visualization::PCLVisualizer> viewer(new pcl::visualization::PCLVisualizer(“3D Viewer”));
 viewer->setBackgroundColor(0, 0, 0); //设置背景
 viewer->addPointCloud(cloudOutput,”cloudssd”);

 while (!viewer->wasStopped()){
  viewer->spinOnce();
 }
 //pcl::io::savePCDFileASCII(strOutPutPointCloudName, cloudOutput);
 //cloudOutput.clear();
}

//读入点云，写.las

void writeLasFromPointCloud3(const char* strInputPointCloudName, const char* strOutLasName)
{
 std::ofstream ofs(strOutLasName, ios::out | ios::binary);
 if (!ofs.is_open())
 {
  std::cout << “err  to  open  file  las…..” << std::endl;
  return;
 }
 liblas::Header header;
 header.SetVersionMajor(1);
 header.SetVersionMinor(2);
 header.SetDataFormatId(liblas::PointFormatName::ePointFormat3);
 header.SetScale(0.001, 0.001, 0.001);

 pcl::PointCloud<pcl::PointXYZRGBA>::Ptr cloud(new pcl::PointCloud<pcl::PointXYZRGBA>);
 pcl::io::loadPCDFile(strInputPointCloudName, *cloud);
 std::cout << “总数:” << cloud->points.size() << std::endl;
 //写liblas,
 liblas::Writer writer(ofs, header);
 liblas::Point point(&header);

 for (size_t i = 0; i < cloud->points.size(); i++)
 {
  double x = cloud->points[i].x;
  double y = cloud->points[i].y;
  double z = cloud->points[i].z;
  point.SetCoordinates(x, y, z);

  uint32_t red = (uint32_t)cloud->points[i].r;
  uint32_t green = (uint32_t)cloud->points[i].g;
  uint32_t blue = (uint32_t)cloud->points[i].b;
  liblas::Color pointColor(red, green, blue);
  point.SetColor(pointColor);
  writer.WritePoint(point);
  //std::cout << x << “,” << y << “,” << z << std::endl;
 }
 double minPt[3] = { 9999999, 9999999, 9999999 };
 double maxPt[3] = { 0, 0, 0 };
 header.SetPointRecordsCount(cloud->points.size());
 header.SetPointRecordsByReturnCount(0, cloud->points.size());
 header.SetMax(maxPt[0], maxPt[1], maxPt[2]);
 header.SetMin(minPt[0], minPt[1], minPt[2]);
 writer.SetHeader(header);
}

int main()
{
 //char strInputLasName[] = “qq.las”;//”Scan_az001.las”;
 //char strOutPutPointCloudName[]=”qqqq.pcd”;
 //writePointCloudFromLas(strInputLasName, strOutPutPointCloudName);

 //std::string strInputPointCloudName = “eewge”;
 //std::string strOutLasName = “eewge”;
 //writeLasFromPointCloud(strInputPointCloudName.c_str(), strOutLasName.c_str());
 char strInputPointCloudName[] = “qq.pcd”;
 char strOutLasName[] = “qq.las”;
 writeLasFromPointCloud3(strInputPointCloudName, strOutLasName);

 return 0;
}