Add position ground truth. (#5819)

Have confirmed this works with gazebo sitl.

src/modules/simulator/simulator.h

@@ -43,6 +43,7 @@
 #include <uORB/topics/manual_control_setpoint.h>
 #include <uORB/topics/actuator_outputs.h>
 #include <uORB/topics/vehicle_attitude.h>
+#include <uORB/topics/vehicle_global_position.h>
 #include <uORB/topics/vehicle_status.h>
 #include <uORB/topics/battery_status.h>
 #include <drivers/drv_accel.h>
@@ -58,6 +59,7 @@
 #include <uORB/topics/distance_sensor.h>
 #include <v1.0/mavlink_types.h>
 #include <v1.0/common/mavlink.h>
+#include <geo/geo.h>
 namespace simulator
 {
 
@@ -247,10 +249,17 @@ private:
 		,
 		_rc_channels_pub(nullptr),
 		_attitude_pub(nullptr),
+		_gpos_pub(nullptr),
 		_actuator_outputs_sub{},
 		_vehicle_attitude_sub(-1),
 		_manual_sub(-1),
 		_vehicle_status_sub(-1),
+		_hil_local_proj_ref(),
+		_hil_local_proj_inited(false),
+		_hil_ref_lat(0),
+		_hil_ref_lon(0),
+		_hil_ref_alt(0),
+		_hil_ref_timestamp(0),
 		_rc_input{},
 		_actuators{},
 		_attitude{},
@@ -317,6 +326,8 @@ private:
 	// uORB publisher handlers
 	orb_advert_t _rc_channels_pub;
 	orb_advert_t _attitude_pub;
+	orb_advert_t _gpos_pub;
+	orb_advert_t _lpos_pub;
 
 	// uORB subscription handlers
 	int _actuator_outputs_sub[ORB_MULTI_MAX_INSTANCES];
@@ -324,6 +335,14 @@ private:
 	int _manual_sub;
 	int _vehicle_status_sub;
 
+	// hil map_ref data
+	struct map_projection_reference_s _hil_local_proj_ref;
+	bool _hil_local_proj_inited;
+	double _hil_ref_lat;
+	double _hil_ref_lon;
+	float _hil_ref_alt;
+	uint64_t _hil_ref_timestamp;
+
 	// uORB data containers
 	struct rc_input_values _rc_input;
 	struct actuator_outputs_s _actuators[ORB_MULTI_MAX_INSTANCES];