text: /***************************************************************************
   *
   *   Copyright (c) 2013-2014 PX4 Development Team. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. 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.
   * 3. Neither the name PX4 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
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   * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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   ****************************************************************************/
  /**
   * @file navigator_rtl.h
   * Helper class for RTL
   *
   * @author Julian Oes <julian@oes.ch>
   * @author Anton Babushkin <anton.babushkin@me.com>
   */
  
  #ifndef NAVIGATOR_RTL_H
  #define NAVIGATOR_RTL_H
  
  #include <controllib/blocks.hpp>
  #include <controllib/block/BlockParam.hpp>
  
  #include <navigator/navigation.h>
  #include <uORB/topics/home_position.h>
  #include <uORB/topics/vehicle_global_position.h>
  
  #include "navigator_mode.h"
  #include "mission_block.h"
  
  class Navigator;
  
  class RTL : public MissionBlock
  {
  public:
  	RTL(Navigator *navigator, const char *name);
  
  	~RTL();
  
  	virtual void on_inactive();
  
  	virtual void on_activation();
  
  	virtual void on_active();
  
  private:
  	/**
  	 * Set the RTL item
  	 */
  	void		set_rtl_item();
  
  	/**
  	 * Move to next RTL item
  	 */
  	void		advance_rtl();
  
  	enum RTLState {
  		RTL_STATE_NONE = 0,
  		RTL_STATE_CLIMB,
  		RTL_STATE_RETURN,
  		RTL_STATE_TRANSITION_TO_MC,
  		RTL_STATE_DESCEND,
  		RTL_STATE_LOITER,
  		RTL_STATE_LAND,
  		RTL_STATE_LANDED,
  	} _rtl_state;
  
  	bool _rtl_start_lock;
  
  	control::BlockParamFloat _param_return_alt;
  	control::BlockParamFloat _param_min_loiter_alt;
  	control::BlockParamFloat _param_descend_alt;
  	control::BlockParamFloat _param_land_delay;
  	control::BlockParamFloat _param_rtl_min_dist;
  };
  
  #endif
  