Merge pull request #893 from PX4/geo

GEO lib projection changes / updates

src/lib/geo/geo.c

 /****************************************************************************
  *
- *   Copyright (C) 2012, 2014 PX4 Development Team. All rights reserved.
+ *   Copyright (c) 2012-2014 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
@@ -49,39 +49,124 @@
 #include <stdio.h>
 #include <math.h>
 #include <stdbool.h>
+#include <string.h>
+#include <float.h>
+
+#include <systemlib/err.h>
+#include <drivers/drv_hrt.h>
 
 /*
  * Azimuthal Equidistant Projection
  * formulas according to: http://mathworld.wolfram.com/AzimuthalEquidistantProjection.html
  */
 
-__EXPORT void map_projection_init(struct map_projection_reference_s *ref, double lat_0, double lon_0) //lat_0, lon_0 are expected to be in correct format: -> 47.1234567 and not 471234567
+static struct map_projection_reference_s mp_ref = {0.0, 0.0, 0.0, 0.0, false, 0};
+static struct globallocal_converter_reference_s gl_ref = {0.0f, false};
+
+__EXPORT bool map_projection_global_initialized()
+{
+	return map_projection_initialized(&mp_ref);
+}
+
+__EXPORT bool map_projection_initialized(const struct map_projection_reference_s *ref)
+{
+	return ref->init_done;
+}
+
+__EXPORT uint64_t map_projection_global_timestamp()
+{
+	return map_projection_timestamp(&mp_ref);
+}
+
+__EXPORT uint64_t map_projection_timestamp(const struct map_projection_reference_s *ref)
 {
-	ref->lat = lat_0 / 180.0 * M_PI;
-	ref->lon = lon_0 / 180.0 * M_PI;
+	return ref->timestamp;
+}
 
-	ref->sin_lat = sin(ref->lat);
-	ref->cos_lat = cos(ref->lat);
+__EXPORT int map_projection_global_init(double lat_0, double lon_0, uint64_t timestamp) //lat_0, lon_0 are expected to be in correct format: -> 47.1234567 and not 471234567
+{
+	if (strcmp("commander", getprogname()) == 0) {
+		return map_projection_init_timestamped(&mp_ref, lat_0, lon_0, timestamp);
+	} else {
+		return -1;
+	}
 }
 
-__EXPORT void map_projection_project(struct map_projection_reference_s *ref, double lat, double lon, float *x, float *y)
+__EXPORT int map_projection_init_timestamped(struct map_projection_reference_s *ref, double lat_0, double lon_0, uint64_t timestamp) //lat_0, lon_0 are expected to be in correct format: -> 47.1234567 and not 471234567
 {
-	double lat_rad = lat / 180.0 * M_PI;
-	double lon_rad = lon / 180.0 * M_PI;
+
+	ref->lat_rad = lat_0 * M_DEG_TO_RAD;
+	ref->lon_rad = lon_0 * M_DEG_TO_RAD;
+	ref->sin_lat = sin(ref->lat_rad);
+	ref->cos_lat = cos(ref->lat_rad);
+
+	ref->timestamp = timestamp;
+	ref->init_done = true;
+
+	return 0;
+}
+
+__EXPORT int map_projection_init(struct map_projection_reference_s *ref, double lat_0, double lon_0) //lat_0, lon_0 are expected to be in correct format: -> 47.1234567 and not 471234567
+{
+	return map_projection_init_timestamped(ref, lat_0, lon_0, hrt_absolute_time());
+}
+
+__EXPORT int map_projection_global_reference(double *ref_lat_rad, double *ref_lon_rad)
+{
+	return map_projection_reference(&mp_ref, ref_lat_rad, ref_lon_rad);
+}
+
+__EXPORT int map_projection_reference(const struct map_projection_reference_s *ref, double *ref_lat_rad, double *ref_lon_rad)
+{
+	if (!map_projection_initialized(ref)) {
+		return -1;
+	}
+
+	*ref_lat_rad = ref->lat_rad;
+	*ref_lon_rad = ref->lon_rad;
+
+	return 0;
+}
+
+__EXPORT int map_projection_global_project(double lat, double lon, float *x, float *y)
+{
+	return map_projection_project(&mp_ref, lat, lon, x, y);
+
+}
+
+__EXPORT int map_projection_project(const struct map_projection_reference_s *ref, double lat, double lon, float *x, float *y)
+{
+	if (!map_projection_initialized(ref)) {
+		return -1;
+	}
+
+	double lat_rad = lat * M_DEG_TO_RAD;
+	double lon_rad = lon * M_DEG_TO_RAD;
 
 	double sin_lat = sin(lat_rad);
 	double cos_lat = cos(lat_rad);
-	double cos_d_lon = cos(lon_rad - ref->lon);
+	double cos_d_lon = cos(lon_rad - ref->lon_rad);
 
 	double c = acos(ref->sin_lat * sin_lat + ref->cos_lat * cos_lat * cos_d_lon);
-	double k = (c == 0.0) ? 1.0 : (c / sin(c));
+	double k = (fabs(c) < DBL_EPSILON) ? 1.0 : (c / sin(c));
 
 	*x = k * (ref->cos_lat * sin_lat - ref->sin_lat * cos_lat * cos_d_lon) * CONSTANTS_RADIUS_OF_EARTH;
-	*y = k * cos_lat * sin(lon_rad - ref->lon) * CONSTANTS_RADIUS_OF_EARTH;
+	*y = k * cos_lat * sin(lon_rad - ref->lon_rad) * CONSTANTS_RADIUS_OF_EARTH;
+
+	return 0;
+}
+
+__EXPORT int map_projection_global_reproject(float x, float y, double *lat, double *lon)
+{
+	return map_projection_reproject(&mp_ref, x, y, lat, lon);
 }
 
-__EXPORT void map_projection_reproject(struct map_projection_reference_s *ref, float x, float y, double *lat, double *lon)
+__EXPORT int map_projection_reproject(const struct map_projection_reference_s *ref, float x, float y, double *lat, double *lon)
 {
+	if (!map_projection_initialized(ref)) {
+		return -1;
+	}
+
 	double x_rad = x / CONSTANTS_RADIUS_OF_EARTH;
 	double y_rad = y / CONSTANTS_RADIUS_OF_EARTH;
 	double c = sqrtf(x_rad * x_rad + y_rad * y_rad);
@@ -91,19 +176,101 @@ __EXPORT void map_projection_reproject(struct map_projection_reference_s *ref, f
 	double lat_rad;
 	double lon_rad;
 
-	if (c != 0.0) {
+	if (fabs(c) > DBL_EPSILON) {
 		lat_rad = asin(cos_c * ref->sin_lat + (x_rad * sin_c * ref->cos_lat) / c);
-		lon_rad = (ref->lon + atan2(y_rad * sin_c, c * ref->cos_lat * cos_c - x_rad * ref->sin_lat * sin_c));
+		lon_rad = (ref->lon_rad + atan2(y_rad * sin_c, c * ref->cos_lat * cos_c - x_rad * ref->sin_lat * sin_c));
 
 	} else {
-		lat_rad = ref->lat;
-		lon_rad = ref->lon;
+		lat_rad = ref->lat_rad;
+		lon_rad = ref->lon_rad;
 	}
 
 	*lat = lat_rad * 180.0 / M_PI;
 	*lon = lon_rad * 180.0 / M_PI;
+
+	return 0;
+}
+
+__EXPORT int map_projection_global_getref(double *lat_0, double *lon_0)
+{
+	if (!map_projection_global_initialized()) {
+		return -1;
+	}
+
+	if (lat_0 != NULL) {
+		*lat_0 = M_RAD_TO_DEG * mp_ref.lat_rad;
+	}
+
+	if (lon_0 != NULL) {
+		*lon_0 = M_RAD_TO_DEG * mp_ref.lon_rad;
+	}
+
+	return 0;
+
+}
+__EXPORT int globallocalconverter_init(double lat_0, double lon_0, float alt_0, uint64_t timestamp)
+{
+	if (strcmp("commander", getprogname()) == 0) {
+		gl_ref.alt = alt_0;
+		if (!map_projection_global_init(lat_0, lon_0, timestamp))
+		{
+			gl_ref.init_done = true;
+			return 0;
+		} else {
+			gl_ref.init_done = false;
+			return -1;
+		}
+	} else {
+		return -1;
+	}
+}
+
+__EXPORT bool globallocalconverter_initialized()
+{
+	return gl_ref.init_done && map_projection_global_initialized();
 }
 
+__EXPORT int globallocalconverter_tolocal(double lat, double lon, float alt, float *x, float *y, float *z)
+{
+	if (!map_projection_global_initialized()) {
+		return -1;
+	}
+
+	map_projection_global_project(lat, lon, x, y);
+	*z = gl_ref.alt - alt;
+
+	return 0;
+}
+
+__EXPORT int globallocalconverter_toglobal(float x, float y, float z,  double *lat, double *lon, float *alt)
+{
+	if (!map_projection_global_initialized()) {
+		return -1;
+	}
+
+	map_projection_global_reproject(x, y, lat, lon);
+	*alt = gl_ref.alt - z;
+
+	return 0;
+}
+
+__EXPORT int globallocalconverter_getref(double *lat_0, double *lon_0, float *alt_0)
+{
+	if (!map_projection_global_initialized()) {
+		return -1;
+	}
+
+	if (map_projection_global_getref(lat_0, lon_0))
+	{
+		return -1;
+	}
+
+	if (alt_0 != NULL) {
+		*alt_0 = gl_ref.alt;
+	}
+
+	return 0;
+}
 
 __EXPORT float get_distance_to_next_waypoint(double lat_now, double lon_now, double lat_next, double lon_next)
 {

src/lib/geo/geo.h

@@ -69,39 +69,162 @@ struct crosstrack_error_s {
 
 /* lat/lon are in radians */
 struct map_projection_reference_s {
-	double lat;
-	double lon;
+	double lat_rad;
+	double lon_rad;
 	double sin_lat;
 	double cos_lat;
+	bool init_done;
+	uint64_t timestamp;
 };
 
+struct globallocal_converter_reference_s {
+	float alt;
+	bool init_done;
+};
+
+/**
+ * Checks if global projection was initialized
+ * @return true if map was initialized before, false else
+ */
+__EXPORT bool map_projection_global_initialized(void);
+
+/**
+ * Checks if projection given as argument was initialized
+ * @return true if map was initialized before, false else
+ */
+__EXPORT bool map_projection_initialized(const struct map_projection_reference_s *ref);
+
+/**
+ * Get the timestamp of the global map projection
+ * @return the timestamp of the map_projection
+ */
+__EXPORT uint64_t map_projection_global_timestamp(void);
+
+/**
+ * Get the timestamp of the map projection given by the argument
+ * @return the timestamp of the map_projection
+ */
+__EXPORT uint64_t map_projection_timestamp(const struct map_projection_reference_s *ref);
+
+/**
+ * Writes the reference values of the global projection to ref_lat and ref_lon
+ * @return 0 if map_projection_init was called before, -1 else
+ */
+__EXPORT int map_projection_global_reference(double *ref_lat_rad, double *ref_lon_rad);
+
 /**
- * Initializes the map transformation.
+ * Writes the reference values of the projection given by the argument to ref_lat and ref_lon
+ * @return 0 if map_projection_init was called before, -1 else
+ */
+__EXPORT int map_projection_reference(const struct map_projection_reference_s *ref, double *ref_lat_rad, double *ref_lon_rad);
+
+/**
+ * Initializes the global 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 int map_projection_global_init(double lat_0, double lon_0, uint64_t timestamp);
+
+/**
+ * Initializes the map transformation given by the argument.
+ *
+ * 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 int map_projection_init_timestamped(struct map_projection_reference_s *ref,
+		double lat_0, double lon_0, uint64_t timestamp);
+
+/**
+ * Initializes the map transformation given by the argument and sets the timestamp to now.
  *
- * Initializes the transformation between the geographic coordinate system and the azimuthal equidistant plane
+ * 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(struct map_projection_reference_s *ref, double lat_0, double lon_0);
+__EXPORT int map_projection_init(struct map_projection_reference_s *ref, double lat_0, double lon_0);
 
 /**
- * Transforms a point in the geographic coordinate system to the local azimuthal equidistant plane
+ * Transforms a point in the geographic coordinate system to the local
+ * azimuthal equidistant plane using the global projection
  * @param x north
  * @param y east
  * @param lat in degrees (47.1234567°, not 471234567°)
  * @param lon in degrees (8.1234567°, not 81234567°)
+ * @return 0 if map_projection_init was called before, -1 else
  */
-__EXPORT void map_projection_project(struct map_projection_reference_s *ref, double lat, double lon, float *x, float *y);
+__EXPORT int map_projection_global_project(double lat, double lon, float *x, float *y);
+
+
+ /* Transforms a point in the geographic coordinate system to the local
+  * azimuthal equidistant plane using the projection given by the argument
+ * @param x north
+ * @param y east
+ * @param lat in degrees (47.1234567°, not 471234567°)
+ * @param lon in degrees (8.1234567°, not 81234567°)
+ * @return 0 if map_projection_init was called before, -1 else
+ */
+__EXPORT int map_projection_project(const struct map_projection_reference_s *ref, double lat, double lon, float *x, float *y);
+
+/**
+ * Transforms a point in the local azimuthal equidistant plane to the
+ * geographic coordinate system using the global projection
+ *
+ * @param x north
+ * @param y east
+ * @param lat in degrees (47.1234567°, not 471234567°)
+ * @param lon in degrees (8.1234567°, not 81234567°)
+ * @return 0 if map_projection_init was called before, -1 else
+ */
+__EXPORT int map_projection_global_reproject(float x, float y, double *lat, double *lon);
 
 /**
- * Transforms a point in the local azimuthal equidistant plane to the geographic coordinate system
+ * Transforms a point in the local azimuthal equidistant plane to the
+ * geographic coordinate system using the projection given by the argument
  *
  * @param x north
  * @param y east
  * @param lat in degrees (47.1234567°, not 471234567°)
  * @param lon in degrees (8.1234567°, not 81234567°)
+ * @return 0 if map_projection_init was called before, -1 else
+ */
+__EXPORT int map_projection_reproject(const struct map_projection_reference_s *ref, float x, float y, double *lat, double *lon);
+
+/**
+ * Get reference position of the global map projection
+ */
+__EXPORT int map_projection_global_getref(double *lat_0, double *lon_0);
+
+/**
+ * Initialize the global mapping between global position (spherical) and local position (NED).
+ */
+__EXPORT int globallocalconverter_init(double lat_0, double lon_0, float alt_0, uint64_t timestamp);
+
+/**
+ * Checks if globallocalconverter was initialized
+ * @return true if map was initialized before, false else
+ */
+__EXPORT bool globallocalconverter_initialized(void);
+
+/**
+ * Convert from global position coordinates to local position coordinates using the global reference
+ */
+__EXPORT int globallocalconverter_tolocal(double lat, double lon, float alt, float *x, float *y, float *z);
+
+/**
+ * Convert from local position coordinates to global position coordinates using the global reference
+ */
+__EXPORT int globallocalconverter_toglobal(float x, float y, float z,  double *lat, double *lon, float *alt);
+
+/**
+ * Get reference position of the global to local converter
  */
-__EXPORT void map_projection_reproject(struct map_projection_reference_s *ref, float x, float y, double *lat, double *lon);
+__EXPORT int globallocalconverter_getref(double *lat_0, double *lon_0, float *alt_0);
 
 /**
  * Returns the distance to the next waypoint in meters.

src/modules/commander/commander.cpp

@@ -59,6 +59,7 @@
 #include <string.h>
 #include <math.h>
 #include <poll.h>
+#include <float.h>
 
 #include <uORB/uORB.h>
 #include <uORB/topics/sensor_combined.h>
@@ -92,6 +93,7 @@
 #include <systemlib/err.h>
 #include <systemlib/cpuload.h>
 #include <systemlib/rc_check.h>
+#include <geo/geo.h>
 #include <systemlib/state_table.h>
 #include <dataman/dataman.h>
 
@@ -875,6 +877,8 @@ int commander_thread_main(int argc, char *argv[])
 	int gps_sub = orb_subscribe(ORB_ID(vehicle_gps_position));
 	struct vehicle_gps_position_s gps_position;
 	memset(&gps_position, 0, sizeof(gps_position));
+	gps_position.eph = FLT_MAX;
+	gps_position.epv = FLT_MAX;
 
 	/* Subscribe to sensor topic */
 	int sensor_sub = orb_subscribe(ORB_ID(sensor_combined));
@@ -1335,6 +1339,16 @@ int commander_thread_main(int argc, char *argv[])
 			orb_copy(ORB_ID(vehicle_gps_position), gps_sub, &gps_position);
 		}
 
+		/* Initialize map projection if gps is valid */
+		if (!map_projection_global_initialized()
+				&& (gps_position.eph < eph_threshold)
+				&& (gps_position.epv < epv_threshold)
+				&& hrt_elapsed_time((hrt_abstime*)&gps_position.timestamp_position) < 1e6) {
+			/* set reference for global coordinates <--> local coordiantes conversion and map_projection */
+			globallocalconverter_init((double)gps_position.lat * 1.0e-7, (double)gps_position.lon * 1.0e-7, (float)gps_position.alt * 1.0e-3f, hrt_absolute_time());
+		}
+
+		/* start mission result check */
 		orb_check(mission_result_sub, &updated);
 
 		if (updated) {