diff options
Diffstat (limited to 'src/lib/geo/geo.h')
| -rw-r--r-- | src/lib/geo/geo.h | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/src/lib/geo/geo.h b/src/lib/geo/geo.h new file mode 100644 index 000000000..dadec51ec --- /dev/null +++ b/src/lib/geo/geo.h @@ -0,0 +1,129 @@ +/**************************************************************************** + * + * Copyright (C) 2012 PX4 Development Team. All rights reserved. + * Author: Thomas Gubler <thomasgubler@student.ethz.ch> + * Julian Oes <joes@student.ethz.ch> + * Lorenz Meier <lm@inf.ethz.ch> + * + * 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 + * 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. + * + ****************************************************************************/ + +/** + * @file geo.h + * + * Definition of geo / math functions to perform geodesic calculations + * + * @author Thomas Gubler <thomasgubler@student.ethz.ch> + * @author Julian Oes <joes@student.ethz.ch> + * @author Lorenz Meier <lm@inf.ethz.ch> + * Additional functions - @author Doug Weibel <douglas.weibel@colorado.edu> + */ + +#pragma once + +__BEGIN_DECLS + +#include <stdbool.h> + +#define CONSTANTS_ONE_G 9.80665f /* m/s^2 */ +#define CONSTANTS_AIR_DENSITY_SEA_LEVEL_15C 1.225f /* kg/m^3 */ +#define CONSTANTS_AIR_GAS_CONST 287.1f /* J/(kg * K) */ +#define CONSTANTS_ABSOLUTE_NULL_CELSIUS -273.15f /* °C */ +#define CONSTANTS_RADIUS_OF_EARTH 6371000 /* meters (m) */ + +/* compatibility aliases */ +#define RADIUS_OF_EARTH CONSTANTS_RADIUS_OF_EARTH +#define GRAVITY_MSS CONSTANTS_ONE_G + +// XXX remove +struct crosstrack_error_s { + bool past_end; // Flag indicating we are past the end of the line/arc segment + float distance; // Distance in meters to closest point on line/arc + float bearing; // Bearing in radians to closest point on line/arc +} ; + +/** + * Initializes the map transformation. + * + * Initializes the transformation between the geographic coordinate system and the azimuthal equidistant plane + * @param lat in degrees (47.1234567°, not 471234567°) + * @param lon in degrees (8.1234567°, not 81234567°) + */ +__EXPORT void map_projection_init(double lat_0, double lon_0); + +/** + * Transforms a point in the geographic coordinate system to the local azimuthal equidistant plane + * @param x north + * @param y east + * @param lat in degrees (47.1234567°, not 471234567°) + * @param lon in degrees (8.1234567°, not 81234567°) + */ +__EXPORT void map_projection_project(double lat, double lon, float *x, float *y); + +/** + * Transforms a point in the local azimuthal equidistant plane to the geographic coordinate system + * + * @param x north + * @param y east + * @param lat in degrees (47.1234567°, not 471234567°) + * @param lon in degrees (8.1234567°, not 81234567°) + */ +__EXPORT void map_projection_reproject(float x, float y, double *lat, double *lon); + +/** + * Returns the distance to the next waypoint in meters. + * + * @param lat_now current position in degrees (47.1234567°, not 471234567°) + * @param lon_now current position in degrees (8.1234567°, not 81234567°) + * @param lat_next next waypoint position in degrees (47.1234567°, not 471234567°) + * @param lon_next next waypoint position in degrees (8.1234567°, not 81234567°) + */ +__EXPORT float get_distance_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next); + +/** + * Returns the bearing to the next waypoint in radians. + * + * @param lat_now current position in degrees (47.1234567°, not 471234567°) + * @param lon_now current position in degrees (8.1234567°, not 81234567°) + * @param lat_next next waypoint position in degrees (47.1234567°, not 471234567°) + * @param lon_next next waypoint position in degrees (8.1234567°, not 81234567°) + */ +__EXPORT float get_bearing_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next); + +__EXPORT int get_distance_to_line(struct crosstrack_error_s * crosstrack_error, double lat_now, double lon_now, double lat_start, double lon_start, double lat_end, double lon_end); + +__EXPORT int get_distance_to_arc(struct crosstrack_error_s * crosstrack_error, double lat_now, double lon_now, double lat_center, double lon_center, + float radius, float arc_start_bearing, float arc_sweep); + +__EXPORT float _wrap_180(float bearing); +__EXPORT float _wrap_360(float bearing); +__EXPORT float _wrap_pi(float bearing); +__EXPORT float _wrap_2pi(float bearing); + +__END_DECLS |