/****************************************************************************
 *
 *   Copyright (C) 2013 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
 * 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
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 ****************************************************************************/

/**
 * @file Rangefinder driver interface.
 */

#ifndef _DRV_PX4FLOW_H
#define _DRV_PX4FLOW_H

#include <stdint.h>
#include <sys/ioctl.h>

#include "drv_sensor.h"
#include "drv_orb_dev.h"

#define PX4FLOW_DEVICE_PATH	"/dev/px4flow"

/**
 * @addtogroup topics
 * @{
 */

/**
 * Optical flow in NED body frame in SI units.
 *
 * @see http://en.wikipedia.org/wiki/International_System_of_Units
 *
 * @warning If possible the usage of the raw flow and performing rotation-compensation
 *		using the autopilot angular rate estimate is recommended.
 */
struct px4flow_report {

	uint64_t timestamp;		/**< in microseconds since system start          */

	int16_t flow_raw_x;		/**< flow in pixels in X direction, not rotation-compensated */
	int16_t flow_raw_y;		/**< flow in pixels in Y direction, not rotation-compensated */
	float flow_comp_x_m;		/**< speed over ground in meters per second, rotation-compensated */
	float flow_comp_y_m;		/**< speed over ground in meters per second, rotation-compensated */
	float ground_distance_m;	/**< Altitude / distance to ground in meters */
	uint8_t	quality;		/**< Quality of the measurement, 0: bad quality, 255: maximum quality */
	uint8_t sensor_id;		/**< id of the sensor emitting the flow value */

};

/**
 * @}
 */

/*
 * ObjDev tag for px4flow data.
 */
ORB_DECLARE(optical_flow);

/*
 * ioctl() definitions
 *
 * px4flow drivers also implement the generic sensor driver
 * interfaces from drv_sensor.h
 */

#define _PX4FLOWIOCBASE			(0x7700)
#define __PX4FLOWIOC(_n)		(_IOC(_PX4FLOWIOCBASE, _n))


#endif /* _DRV_PX4FLOW_H */