RoboBuggy

/*

 * Copyright (c) 2009, Willow Garage, Inc.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *

 *     * Redistributions of source code must retain the above copyright

 *       notice, this list of conditions and the following disclaimer.

 *     * Redistributions in binary form must reproduce the above copyright

 *       notice, this list of conditions and the following disclaimer in the

 *       documentation and/or other materials provided with the distribution.

 *     * Neither the name of the Willow Garage, Inc. nor the names of its

 *       contributors may be used to endorse or promote products derived from

 *       this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE

 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGE.

 */

#include "buggysim/buggy.h"

#include <QColor>

#include <QRgb>

#define DEFAULT_PEN_R 0xb3

#define DEFAULT_PEN_G 0xb8

#define DEFAULT_PEN_B 0xff

namespace buggysim

{

   Turtle::Turtle(const ros::NodeHandle& nh, const QImage& turtle_image,

                  const QPointF& pos, float orient)

      : nh_(nh)

      , turtle_image_(turtle_image)

      , pos_(pos)

      , orient_(orient)

      , lin_vel_(2.0)

      //, ang_vel_(0.0)

      , turnAngle_(0.0)

      , pen_on_(true)

      , pen_(QColor(DEFAULT_PEN_R, DEFAULT_PEN_G, DEFAULT_PEN_B))

   {

      pen_.setWidth(3);

      angle_sub_ = nh_.subscribe

                   ("command_turnAngle", 1, &Turtle::turnAngleCallback, this);

      pose_pub_ = nh_.advertise<buggymsgs::Pose>("pose", 1);

      //color_pub_ = nh_.advertise<Color>("color_sensor", 1);

      set_pen_srv_ = nh_.advertiseService

                     ("set_pen", &Turtle::setPenCallback, this);

      teleport_relative_srv_ = nh_.advertiseService

                               ("teleport_relative", &Turtle::teleportRelativeCallback, this);

      teleport_absolute_srv_ = nh_.advertiseService

                               ("teleport_absolute", &Turtle::teleportAbsoluteCallback, this);

      meter_ = turtle_image_.height();

      rotateImage();

   }

   void Turtle::turnAngleCallback(const buggymsgs::DirectionConstPtr& dir)

   {

      last_command_time_ = ros::WallTime::now();

      turnAngle_ = dir->turnAngle;

      //lin_vel_ = vel->linear;

      //ang_vel_ = vel->angular;

   }

   bool Turtle::setPenCallback(buggysim::SetPen::Request& req,

                               buggysim::SetPen::Response&)

   {

      pen_on_ = !req.off;

      if (req.off) {

         return true;

      }

      QPen pen(QColor(req.r, req.g, req.b));

      if (req.width != 0) {

         pen.setWidth(req.width);

      }

      pen_ = pen;

      return true;

   }

   bool Turtle::teleportRelativeCallback(buggysim::TeleportRelative::Request& req,

                                         buggysim::TeleportRelative::Response&)

   {

      teleport_requests_.push_back(TeleportRequest(0, 0, req.angular, req.linear,

                                   true));

      return true;

   }

   bool Turtle::teleportAbsoluteCallback(buggysim::TeleportAbsolute::Request& req,

                                         buggysim::TeleportAbsolute::Response&)

   {

      teleport_requests_.push_back(TeleportRequest(req.x, req.y, req.theta, 0,

                                   false));

      return true;

   }

   void Turtle::rotateImage()

   {

      QTransform transform;

      transform.rotate(-orient_ * 180.0 / PI + 90.0);

      turtle_rotated_image_ = turtle_image_.transformed(transform);

   }

   /**

    * TODO: convert this to take just an angle. And include drag.

    *       and include acceleration/joule dump

    */

   bool Turtle::update(double dt, QPainter& path_painter, const QImage& path_image,

                       qreal canvas_width, qreal canvas_height)

   {

      bool modified = false;

      qreal old_orient = orient_;

      // first process any teleportation requests, in order

      V_TeleportRequest::iterator it = teleport_requests_.begin();

      V_TeleportRequest::iterator end = teleport_requests_.end();

      for (; it != end; ++it) {

         const TeleportRequest& req = *it;

         QPointF old_pos = pos_;

         if (req.relative) {

            orient_ += req.theta;

            pos_.rx() += std::sin(orient_ + PI/2.0) * req.linear;

            pos_.ry() += std::cos(orient_ + PI/2.0) * req.linear;

         } else {

            pos_.setX(req.pos.x());

            pos_.setY(std::max(0.0, static_cast<double>(canvas_height - req.pos.y())));

            orient_ = req.theta;

         }

         path_painter.setPen(pen_);

         path_painter.drawLine(pos_ * meter_, old_pos * meter_);

         modified = true;

      }

      teleport_requests_.clear();

      // Stop moving after 1 second since-last command.

      //if (ros::WallTime::now() - last_command_time_ > ros::WallDuration(1.0))

      //{

      //  lin_vel_ = 0.0;

      //  ang_vel_ = 0.0;

      //}

      // Update my position

      QPointF old_pos = pos_;

      /* Convert coordinate systens

      orient_ = std::fmod(orient_ + ang_vel_ * dt, 2*PI);

      pos_.rx() += std::sin(orient_ + PI/2.0) * lin_vel_ * dt;

      pos_.ry() += std::cos(orient_ + PI/2.0) * lin_vel_ * dt;

      */

      // TODO: what direction does orientation start at 0?

      // TODO: orient might have to become negative

      orient_ = std::fmod(orient_ - turnAngle_ * dt, 2*PI);

      // TODO: why add pi/2? is this just because they got the

      //       sin/cos mixed up?

      //pos_.rx() += std::sin(orient_ + PI/2.0) * lin_vel_ * dt;

      //pos_.ry() += std::cos(orient_ + PI/2.0) * lin_vel_ * dt;

      pos_.rx() += std::cos(orient_) * lin_vel_ * dt;

      pos_.ry() += std::sin(orient_) * lin_vel_ * dt;

      // Find linear velocity

      //qreal lin_vel;

      // Find angular velocity

      //qreal ang_vel;

      // Clamp to screen size

      // TODO: change to use another image, to detect walls.

      if (pos_.x() < 0 || pos_.x() > canvas_width ||

            pos_.y() < 0 || pos_.y() > canvas_height) {

         ROS_WARN("Oh no! I hit the wall! (Clamping from [x=%f, y=%f])", pos_.x(),

                  pos_.y());

      }

      pos_.setX(std::min(std::max(static_cast<double>(pos_.x()), 0.0),

                         static_cast<double>(canvas_width)));

      pos_.setY(std::min(std::max(static_cast<double>(pos_.y()), 0.0),

                         static_cast<double>(canvas_height)));

      // Publish pose of the turtle

      buggymsgs::Pose p;

      p.x = pos_.x();

      p.y = canvas_height - pos_.y();

      p.angle = orient_;

      p.linear_velocity = lin_vel_;

      //p.angular_velocity = ang_vel;

      pose_pub_.publish(p);

      // Figure out (and publish) the color underneath the turtle

      /*{

        Color color;

        QRgb pixel = path_image.pixel((pos_ * meter_).toPoint());

        color.r = qRed(pixel);

        color.g = qGreen(pixel);

        color.b = qBlue(pixel);

        color_pub_.publish(color);

        }*/

      ROS_DEBUG("[%s]: pos_x: %f pos_y: %f theta: %f", nh_.getNamespace().c_str(),

                pos_.x(), pos_.y(), orient_);

      if (orient_ != old_orient) {

         rotateImage();

         modified = true;

      }

      if (pos_ != old_pos) {

         if (pen_on_) {

            path_painter.setPen(pen_);

            path_painter.drawLine(pos_ * meter_, old_pos * meter_);

         }

         modified = true;

      }

      return modified;

   }

   void Turtle::paint(QPainter& painter)

   {

      QPointF p = pos_ * meter_;

      p.rx() -= 0.5 * turtle_rotated_image_.width();

      p.ry() -= 0.5 * turtle_rotated_image_.height();

      painter.drawImage(p, turtle_rotated_image_);

   }

}