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/**
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 * The code in this package was developed using the structure of Willow
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 * Garage's turtlesim package.  It was modified by the CMU Robotics Club
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 * to be used as a simulator for the Colony Scout robot.
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 *
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 * All redistribution of this code is limited to the terms of Willow Garage's
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 * licensing terms, as well as under permission from the CMU Robotics Club.
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 * 
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 * Copyright (c) 2011 Colony Project
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 * 
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 * Permission is hereby granted, free of charge, to any person
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 * obtaining a copy of this software and associated documentation
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 * files (the "Software"), to deal in the Software without
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 * restriction, including without limitation the rights to use,
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 * copy, modify, merge, publish, distribute, sublicense, and/or sell
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 * copies of the Software, and to permit persons to whom the
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 * Software is furnished to do so, subject to the following
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 * conditions:
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 * 
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 * The above copyright notice and this permission notice shall be
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 * included in all copies or substantial portions of the Software.
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 * 
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 * Copyright (c) 2009, Willow Garage, Inc.
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 * All rights reserved.
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 * 
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions are met:
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 * 
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 *    Redistributions of source code must retain the above copyright
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 *       notice, this list of conditions and the following disclaimer.
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 *    Redistributions in binary form must reproduce the above copyright
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 *       notice, this list of conditions and the following disclaimer in the
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 *       documentation and/or other materials provided with the distribution.
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 *    Neither the name of the Willow Garage, Inc. nor the names of its
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 *       contributors may be used to endorse or promote products derived from
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 *       this software without specific prior written permission.
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 * 
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 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
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 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
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 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
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 * OTHER DEALINGS IN THE SOFTWARE.
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 */
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#include "scout.h"
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#include <wx/wx.h>
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#define DEFAULT_PEN_R 0xb3
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#define DEFAULT_PEN_G 0xb8
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#define DEFAULT_PEN_B 0xff
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using namespace std;
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namespace scoutsim
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{
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    Scout::Scout(const ros::NodeHandle& nh,
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                 const wxImage& scout_image,
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                 const Vector2& pos,
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                 wxBitmap *path_bitmap,
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                 float orient)
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        : path_bitmap(path_bitmap)
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          , sonar_on(sonar_on)
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          , node (nh)
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          , scout_image(scout_image)
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          , pos(pos)
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          , orient(orient)
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          , motor_fl_speed(0)
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          , motor_fr_speed(0)
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          , motor_bl_speed(0)
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          , motor_br_speed(0)
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          , fl_ticks(0)
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          , fr_ticks(0)
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          , bl_ticks(0)
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          , br_ticks(0)
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          , pen_on(true)
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          , pen(wxColour(DEFAULT_PEN_R, DEFAULT_PEN_G, DEFAULT_PEN_B))
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    {
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        pen.SetWidth(3);
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        scout = wxBitmap(scout_image);
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        motors_sub = node.subscribe("set_motors", 1, &Scout::setMotors, this);
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        pose_pub = node.advertise<Pose>("pose", 1);
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        color_pub = node.advertise<Color>("color_sensor", 1);
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        sonar_pub = node.advertise<sonar::sonar_distance>("sonar_distance", 1);
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        set_pen_srv = node.advertiseService("set_pen",
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                                            &Scout::setPenCallback,
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                                            this);
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        query_encoders_srv =
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            node.advertiseService("query_encoders",
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                                  &Scout::query_encoders_callback,
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                                  this);
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        query_linesensor_srv =
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            node.advertiseService("query_linesensor",
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                                  &Scout::query_linesensor_callback,
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                                  this);
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        for (unsigned int i = 0; i < NUM_LINESENSORS; i++)
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        {
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            linesensor_readings.push_back(0);
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        }
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        // Initialize sonar
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        sonar_position = 0;
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        sonar_stop_l = 0;
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        sonar_stop_r = 23;
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        sonar_direction = 1;
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        sonar_tick_time = ros::Duration(scoutsim::SONAR_HALF_SPIN_TIME / 24.0);
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    }
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    /**
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     * A callback function that sets velocity based on a set_motors
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     * request.
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     * @todo Use "callback" in all callback function names? Or remove?
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     */
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    void Scout::setMotors(const motors::set_motors::ConstPtr& msg)
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    {
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        last_command_time = ros::WallTime::now();
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        if(msg->fl_set)
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        {
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            motor_fl_speed = msg->fl_speed;
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        }
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        if(msg->fr_set)
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        {
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            motor_fr_speed = msg->fr_speed;
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        }
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        if(msg->bl_set)
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        {
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            motor_bl_speed = msg->bl_speed;
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        }
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        if(msg->br_set)
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        {
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            motor_br_speed = msg->br_speed;
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        }
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    }
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    bool Scout::setPenCallback(scoutsim::SetPen::Request& req,
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                               scoutsim::SetPen::Response&)
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    {
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        pen_on = !req.off;
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        if (req.off)
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        {
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            return true;
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        }
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        wxPen pen(wxColour(req.r, req.g, req.b));
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        if (req.width != 0)
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        {
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            pen.SetWidth(req.width);
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        }
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        pen = pen;
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        return true;
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    }
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    bool Scout::query_encoders_callback(encoders::query_encoders::Request&,
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                                        encoders::query_encoders::Response& res)
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    {
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        res.fl_distance = fl_ticks;
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        res.fr_distance = fr_ticks;
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        res.bl_distance = bl_ticks;
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        res.br_distance = br_ticks;
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        return true;
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    }
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    bool Scout::query_linesensor_callback(linesensor::query_linesensor::Request&,
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                                          linesensor::query_linesensor::Response& res)
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    {
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        res.readings = linesensor_readings;
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        return true;
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    }
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    // Scale to linesensor value
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    unsigned int Scout::rgb_to_grey(unsigned char r,
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                                    unsigned char g,
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                                    unsigned char b)
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    {
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        // Should be 0 to 255
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        unsigned int grey = ((unsigned int) r + (unsigned int) g + (unsigned int) b) / 3;
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        /// @todo Convert to the proper range
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        return 255 - grey;
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    }
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    unsigned int Scout::trace_sonar(const wxImage& walls_image, int x, int y,
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                                    double robot_theta, int sonar_pos,
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                                    wxMemoryDC& sonar_dc, bool sonar_on)
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    {
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        double angle = robot_theta + (PI * ((float) sonar_pos) / 24.0) - PI / 2;
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        unsigned int d = 0;
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        unsigned int reading = 0;
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        int d_x = 0;
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        int d_y = 0;
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        do
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        {
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            d_x = x + (int) floor(d * cos(angle));
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            d_y = y + (int) floor(d * sin(angle));
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            // Out of image boundary
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            if (d_x < 0 || d_x >= walls_image.GetWidth() ||
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                d_y < 0 || d_y >= walls_image.GetHeight())
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            {
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                return d;
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            }
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            // Max range
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            if (d > scoutsim::SONAR_MAX_RANGE)
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            {
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                return d;
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            }
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            // Get the sonar reading at the current position of the sonar
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            unsigned char r = walls_image.GetRed(d_x, d_y);
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            unsigned char g = walls_image.GetGreen(d_x, d_y);
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            unsigned char b = walls_image.GetBlue(d_x, d_y);
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            reading = rgb_to_grey(r, g, b);
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            d++;
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        }
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        /// @todo Consider using different cutoffs for different features
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        while (reading < 128); /// @todo Get rid of hardcoded stuff like this
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        if(sonar_on)
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        {       
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            if(isFront)
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            {
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                // draw a circle at the wall_x, wall_y where reading > 128
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                sonar_dc.SelectObject(*path_bitmap);
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                sonar_dc.SetBrush(*wxRED_BRUSH); //old value
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                sonar_dc.DrawCircle(wxPoint(old_front_dx,old_front_dy), 2);
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                old_front_dx = d_x;
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                old_front_dy = d_y;
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            }
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            else
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            {
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                // draw a circle at the wall_x, wall_y where reading > 128
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                sonar_dc.SelectObject(*path_bitmap);
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                sonar_dc.SetBrush(*wxRED_BRUSH); //old value
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                sonar_dc.DrawCircle(wxPoint(old_back_dx,old_back_dy), 2);
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                old_back_dx = d_x;
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                old_back_dy = d_y;
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            }
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            sonar_dc.SetBrush(*wxGREEN_BRUSH);  //newest value
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            sonar_dc.DrawCircle( wxPoint(d_x,d_y), 2);
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            if (isFront) //for some reason isFront = (!isFront) is not working
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            {
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                isFront = FALSE;
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            }
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            else
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            {
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                isFront = TRUE;        
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            }
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        }
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        return d;
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    }
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    // x and y is current position of the sonar
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    void Scout::update_sonar(const wxImage& walls_image, int x, int y,
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                             double robot_theta,wxMemoryDC& sonar_dc, bool sonar_on)
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    {
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        // Only rotate the sonar at the correct rate.
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        if (ros::Time::now() - last_sonar_time < sonar_tick_time)
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        {
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            return;
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        }
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        last_sonar_time = ros::Time::now();
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        unsigned int d_front = trace_sonar(walls_image, x, y, robot_theta,
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                                           sonar_position,sonar_dc, sonar_on);
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        unsigned int d_back = trace_sonar(walls_image, x, y, robot_theta,
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                                          sonar_position + 24,sonar_dc, sonar_on);
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        // Publish
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        sonar::sonar_distance msg;
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        msg.pos = sonar_position;
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        msg.distance0 = d_front;
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        msg.distance1 = d_back;
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        sonar_pub.publish(msg);
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        // Update the sonar rotation
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        if (sonar_position + sonar_direction <= sonar_stop_r &&
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            sonar_position + sonar_direction >= sonar_stop_l)
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        {
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            sonar_position = sonar_position + sonar_direction;
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        }
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        else
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        {
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            sonar_direction = -sonar_direction;
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        }
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    }
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    void Scout::update_linesensor(const wxImage& lines_image, int x, int y,
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                                  double robot_theta)
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    {
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        linesensor_readings.clear();
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        double spacing = scout_image.GetWidth() / (NUM_LINESENSORS - 1);
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        for (int s = 0; s < NUM_LINESENSORS; s++)
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        {
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            double offset = -(scout_image.GetWidth() / 2) + s * spacing;
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            int sensor_x = (int) (x - LNSNSR_D * cos(robot_theta) -
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                                  offset * sin(robot_theta));
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            int sensor_y = (int) (y + LNSNSR_D * sin(robot_theta) -
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                                  offset * cos(robot_theta));
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            unsigned char r = lines_image.GetRed(sensor_x, sensor_y);
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            unsigned char g = lines_image.GetGreen(sensor_x, sensor_y);
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            unsigned char b = lines_image.GetBlue(sensor_x, sensor_y);
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            unsigned int reading = rgb_to_grey(r, g, b);
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            linesensor_readings.push_back(reading);
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        }
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    }
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    /// Sends back the position of this scout so scoutsim can save
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    /// the world state
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    geometry_msgs::Pose2D Scout::update(double dt, wxMemoryDC& path_dc,
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                                        wxMemoryDC& sonar_dc,
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                                        bool sonar_on,
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                                        const wxImage& path_image,
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                                        const wxImage& lines_image,
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                                        const wxImage& walls_image,
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                                        wxColour background_color,
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                                        wxColour sonar_color,
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                                        world_state state)
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    {
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        // Assume that the two motors on the same side will be set to
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        // roughly the same speed. Does not account for slip conditions
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        // when they are set to different speeds.
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        float l_speed = (float (motor_fl_speed + motor_bl_speed)) / 2;
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        float r_speed = (float (motor_fr_speed + motor_br_speed)) / 2;
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        // Find linear and angular movement in m
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        float lin_dist = SCOUTSIM_REFRESH_RATE * (l_speed + r_speed) / 2;
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        float ang_dist = SCOUTSIM_REFRESH_RATE * (r_speed - l_speed);
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        Vector2 old_pos = pos;
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        // Update encoders
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        fl_ticks += (unsigned int) (motor_fl_speed * SCOUTSIM_REFRESH_RATE *
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                                    ENCODER_TICKS_PER_METER);
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        fr_ticks += (unsigned int) (motor_fr_speed * SCOUTSIM_REFRESH_RATE *
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                                    ENCODER_TICKS_PER_METER);
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        bl_ticks += (unsigned int) (motor_bl_speed * SCOUTSIM_REFRESH_RATE *
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                                    ENCODER_TICKS_PER_METER);
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        br_ticks += (unsigned int) (motor_br_speed * SCOUTSIM_REFRESH_RATE *
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                                    ENCODER_TICKS_PER_METER);
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        orient = fmod((float) (orient + ang_dist), (float) (2.0 * PI));
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        // Multiply by dt, the time passed (SCOUTSIM_REFRESH_RATE)
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        pos.x += sin(orient + PI/2.0) * lin_dist;
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        pos.y += cos(orient + PI/2.0) * lin_dist;
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        // Clamp to screen size
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        if (pos.x < 0 || pos.x >= state.canvas_width
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                || pos.y < 0 || pos.y >= state.canvas_height)
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        {
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            ROS_WARN("I hit the wall! (Clamping from [x=%f, y=%f])", pos.x, pos.y);
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        }
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        pos.x = min(max(pos.x, 0.0f), state.canvas_width);
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        pos.y = min(max(pos.y, 0.0f), state.canvas_height);
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        int canvas_x = pos.x * PIX_PER_METER;
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        int canvas_y = pos.y * PIX_PER_METER;
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        {
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            wxImage rotated_image =
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                scout_image.Rotate(orient - PI/2.0,
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                                   wxPoint(scout_image.GetWidth() / 2,
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                                           scout_image.GetHeight() / 2),
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                                   false);
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            for (int y = 0; y < rotated_image.GetHeight(); ++y)
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            {
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                for (int x = 0; x < rotated_image.GetWidth(); ++x)
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                {
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                    if (rotated_image.GetRed(x, y) == 255
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                            && rotated_image.GetBlue(x, y) == 255
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                            && rotated_image.GetGreen(x, y) == 255)
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                    {
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                        rotated_image.SetAlpha(x, y, 0);
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                    }
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                }
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            }
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            scout = wxBitmap(rotated_image);
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        }
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        Pose p;
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        p.x = pos.x;
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        p.y = state.canvas_height - pos.y;
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        p.theta = orient;
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        p.linear_velocity = l_speed;
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        p.angular_velocity = r_speed;
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        pose_pub.publish(p);
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        update_linesensor(lines_image, canvas_x, canvas_y, p.theta);
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        update_sonar(walls_image,
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                     canvas_x + scoutsim::SCOUT_SONAR_X,
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                     canvas_y + scoutsim::SCOUT_SONAR_Y,
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                     p.theta,sonar_dc,sonar_on);
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        // Figure out (and publish) the color underneath the scout
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        {
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            //wxSize scout_size = wxSize(scout.GetWidth(), scout.GetHeight());
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            Color color;
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            color.r = path_image.GetRed(canvas_x, canvas_y);
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            color.g = path_image.GetGreen(canvas_x, canvas_y);
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            color.b = path_image.GetBlue(canvas_x, canvas_y);
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            color_pub.publish(color);
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        }
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        ROS_DEBUG("[%s]: pos_x: %f pos_y: %f theta: %f",
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                  node.getNamespace().c_str(), pos.x, pos.y, orient);
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        if (pen_on)
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        {
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            if (pos != old_pos)
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            {
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                path_dc.SelectObject(*path_bitmap);
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                path_dc.SetPen(pen);
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                path_dc.DrawLine(pos.x * PIX_PER_METER, pos.y * PIX_PER_METER,
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                                 old_pos.x * PIX_PER_METER, old_pos.y * PIX_PER_METER);
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            }
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        }
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        geometry_msgs::Pose2D my_pose;
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        my_pose.x = pos.x;
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        my_pose.y = pos.y;
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        my_pose.theta = orient;
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        return my_pose;
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    }
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    void Scout::paint(wxDC& dc)
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    {
456
        wxSize scout_size = wxSize(scout.GetWidth(), scout.GetHeight());
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        dc.DrawBitmap(scout, pos.x * PIX_PER_METER - (scout_size.GetWidth() / 2),
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                      pos.y * PIX_PER_METER - (scout_size.GetHeight() / 2), true);
459
    }
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}