Quadrotor

/* This file is part of RGBDSLAM.

 * 

 * RGBDSLAM is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 * 

 * RGBDSLAM is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 * 

 * You should have received a copy of the GNU General Public License

 * along with RGBDSLAM.  If not, see <http://www.gnu.org/licenses/>.

 */

 /*

 * gicp.cpp

 *

 *  Created on: Jan 23, 2011

 *      Author: engelhar

 */

#include "gicp-fallback.h"

#include <fstream>

#include <sstream>

#include <iostream>

#include <pcl/filters/voxel_grid.h>

using namespace std;

void saveCloud(const char* filename, const PointCloud_RGB& pc, const int max_cnt, const bool color){

    ofstream of;

    of.open(filename);

    assert(of.is_open());

    int write_step = 1;

    if (max_cnt>0 && (int)pc.points.size()>max_cnt)

        write_step = floor(pc.points.size()*1.0/max_cnt);

    int cnt = 0;

    assert(write_step > 0);

    // only write every write_step.th points

    for (unsigned int i=0; i<pc.points.size(); i += write_step)

    {

        Point p = pc.points[i];

        bool invalid = (isnan(p.x) || isnan(p.y) || isnan(p.z));

        if (invalid)

                continue;

        of << p.x << "\t" << p.y << "\t" << p.z;

        if (color) {

                int color = *reinterpret_cast<const int*>(&p.rgb); 

                int r = (0xff0000 & color) >> 16;

                int g = (0x00ff00 & color) >> 8;

                int b = 0x0000ff & color; 

                of << "\t \t" << r << "\t" << g << "\t" << b << "\t" << endl;

        }        

        else

                of << endl;

       // cout << p.x << "\t" << p.y << "\t" << p.z << endl;

        cnt++;

    }

   // ROS_INFO("gicp.cpp:  saved %i pts (of %i) to %s", cnt,(int) pc.points.size(), filename);

   // printf("gicp.cpp:  saved %i pts (of %i) to %s \n", cnt,(int) pc.points.size(), filename);

    of.close();

}

void downSample(const PointCloud_RGB& src, PointCloud_RGB& to){

    pcl::VoxelGrid<Point> down_sampler;

    down_sampler.setLeafSize (0.01, 0.01, 0.01);

    pcl::PCLBase<Point>::PointCloudConstPtr const_cloud_ptr = boost::make_shared<PointCloud_RGB> (src);

    down_sampler.setInputCloud (const_cloud_ptr);

    down_sampler.filter(to);

    ROS_INFO("gicp.cpp: Downsampling from %i to %i", (int) src.points.size(), (int) to.points.size());

}

bool gicpfallback(const PointCloud_RGB& from, const PointCloud_RGB& to, Eigen::Matrix4f& transform){

        // std::clock_t starttime_gicp = std::clock();

    FILE *fp;

    char f1[200];

    char f2[200];

    char line[130];

    char cmd[200];

    sprintf(f1, "pc1.txt");

    sprintf(f2, "pc2.txt");

    // default values for algo work well on this data

    sprintf(cmd, "./gicp/test_gicp %s %s --d_max 0.01  --debug 0",f1,f2); 

    int N = 40000;

    saveCloud(f1,from,N);

    saveCloud(f2,to,N);

    // cout << "time for writing: " << ((std::clock()-starttime_gicp*1.0) / (double)CLOCKS_PER_SEC) << endl;

    // std::clock_t starttime_gicp2 = std::clock();

    /*

     ICP is calculated by external program. It writes some intermediate results

     and the final homography on stdout, which is parsed here.

     Not very beautiful, but works :)

     */

    fp = popen(cmd, "r");

    std::vector<string> lines;

    // collect all output

    while ( fgets( line, sizeof line, fp))

    {

        lines.push_back(line);

        // ROS_INFO("gicp.cpp: %s", line);

    }

    int retval = pclose(fp);

   // cout << "time for binary: " << ((std::clock()-starttime_gicp2*1.0) / (double)CLOCKS_PER_SEC) << endl;

   // std::clock_t starttime_gicp3 = std::clock();

    if(retval != 0){

        ROS_ERROR_ONCE("Non-zero return value from %s: %i. Identity transformation is returned instead of GICP result.\nThis error will be reported only once.", cmd, retval);

        transform = Eigen::Matrix<float, 4, 4>::Identity();

        return false;

    }

    int pos = 0;

    // last lines contain the transformation:

    for (unsigned int i=lines.size()-5; i<lines.size()-1; i++){

        stringstream ss(lines.at(i));

        for (int j=0; j<4; j++)

        {

            ss >> line;

            transform(pos,j) = atof(line);

        }

        // cout << endl;

        pos++;

    }

    // read the number of iterations:

    stringstream ss(lines.at(lines.size()-1));

    ss >> line; // Converged in

    ss >> line;

    ss >> line;

    int iter_cnt;

    iter_cnt = atoi(line);

    return iter_cnt < 200; // check test_gicp for maximal allowed number of iterations

    // ROS_INFO_STREAM("Parsed: Converged in " << iter_cnt << "iterations");

    // ROS_DEBUG_STREAM("Matrix read from ICP process: " << transform);

    // ROS_INFO_STREAM("Paper: time for icp1 (internal): " << ((std::clock()-starttime_gicp*1.0) / (double)CLOCKS_PER_SEC));

}