laser.cpp

/*
** laser.cc
** Login : <mandor@ithaqua>
** Started on  Wed Jun  3 00:41:29 2009 mandor
** $Id$
**
** Copyright (C) 2009 mandor
** This program 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 2 of the License, or
** (at your option) any later version.
**
** This program 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 this program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/

#include <iostream>
#include "laser.hpp"

namespace fastsim {
  float Laser :: update(const Posture& pos,
                        const boost::shared_ptr<Map>& m) {
    float x2 = cosf(_angle + pos.theta()) * _range + pos.x() + _gap_dist * cosf(_gap_angle + pos.theta());
    float y2 = sinf(_angle + pos.theta()) * _range + pos.y() + _gap_dist * sinf(_gap_angle + pos.theta());



    // convert to pixel
    int xx1 = m->real_to_pixel(pos.x() + _gap_dist * cosf(_gap_angle + pos.theta()));
    int yy1 = m->real_to_pixel(pos.y() + _gap_dist * sinf(_gap_angle + pos.theta()));
    int xx2 = m->real_to_pixel(x2);
    int yy2 = m->real_to_pixel(y2);

    // check intersection

    _x_pixel = m->real_to_pixel(x2), _y_pixel = m->real_to_pixel(y2);

    bool inter = m->check_inter_pixel(xx1, yy1, xx2, yy2, _x_pixel, _y_pixel);
    _x_pixel = std::min(std::max(0, _x_pixel), (int)m->get_pixel_w());
    _y_pixel = std::min(std::max(0, _y_pixel), (int)m->get_pixel_h())
    ;
    assert(_x_pixel >= 0);
    assert(_y_pixel >= 0);

    // convert back to real
    _x = m->pixel_to_real(_x_pixel);
    _y = m->pixel_to_real(_y_pixel);

    //
    if (!inter)
      _dist = -1;
    else {
      float px = pos.x() + _gap_dist * cosf(_gap_angle + pos.theta()) - _x;
      float py = pos.y() + _gap_dist * sinf(_gap_angle + pos.theta()) - _y;
      _dist = sqrtf(px * px  + py * py);
    }
    return _dist;
  }

}