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Initial revision.

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curt 2002-04-04 20:50:05 +00:00
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commit 2c00e13157
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src/ATC/ATCutils.cxx
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// Utility functions for the ATC / AI system
#include <math.h>
#include <simgear/math/point3d.hxx>
#include <simgear/constants.h>
#include <plib/sg.h>
// Given two positions, get the HORIZONTAL separation (in meters)
double dclGetHorizontalSeparation(Point3D pos1, Point3D pos2) {
double x; //East-West separation
double y; //North-South separation
double z; //Horizontal separation - z = sqrt(x^2 + y^2)
double lat1 = pos1.lat() * SG_DEGREES_TO_RADIANS;
double lon1 = pos1.lon() * SG_DEGREES_TO_RADIANS;
double lat2 = pos2.lat() * SG_DEGREES_TO_RADIANS;
double lon2 = pos2.lon() * SG_DEGREES_TO_RADIANS;
y = sin(fabs(lat1 - lat2)) * SG_EQUATORIAL_RADIUS_M;
x = sin(fabs(lon1 - lon2)) * SG_EQUATORIAL_RADIUS_M * (cos((lat1 + lat2) / 2.0));
z = sqrt(x*x + y*y);
return(z);
}
// Given a position (lat/lon/elev), heading, vertical angle, and distance, calculate the new position.
// Assumes that the ground is not hit!!! Expects heading and angle in degrees, distance in meters.
Point3D dclUpdatePosition(Point3D pos, double heading, double angle, double distance) {
double lat = pos.lat() * SG_DEGREES_TO_RADIANS;
double lon = pos.lon() * SG_DEGREES_TO_RADIANS;
double elev = pos.elev();
double horiz_dist = distance * cos(angle);
double vert_dist = distance * sin(angle);
double north_dist = horiz_dist * cos(heading);
double east_dist = horiz_dist * sin(heading);
lat += asin(north_dist / SG_EQUATORIAL_RADIUS_M);
lon += asin(east_dist / SG_EQUATORIAL_RADIUS_M) * (1.0 / cos(lat)); // I suppose really we should use the average of the original and new lat but we'll assume that this will be good enough.
elev += vert_dist;
return(Point3D(lon*SG_RADIANS_TO_DEGREES, lat*SG_RADIANS_TO_DEGREES, elev));
}
#if 0
/* Determine location in runway coordinates */
Radius_to_rwy = Sea_level_radius + Runway_altitude;
cos_rwy_hdg = cos(Runway_heading*DEG_TO_RAD);
sin_rwy_hdg = sin(Runway_heading*DEG_TO_RAD);
D_cg_north_of_rwy = Radius_to_rwy*(Latitude - Runway_latitude);
D_cg_east_of_rwy = Radius_to_rwy*cos(Runway_latitude)
*(Longitude - Runway_longitude);
D_cg_above_rwy = Radius_to_vehicle - Radius_to_rwy;
X_cg_rwy = D_cg_north_of_rwy*cos_rwy_hdg
+ D_cg_east_of_rwy*sin_rwy_hdg;
Y_cg_rwy =-D_cg_north_of_rwy*sin_rwy_hdg
+ D_cg_east_of_rwy*cos_rwy_hdg;
H_cg_rwy = D_cg_above_rwy;
#endif

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src/ATC/ATCutils.hxx Normal file
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// Utility functions for the ATC / AI subsytem declarations
#include <math.h>
#include <simgear/math/point3d.hxx>
// Given two positions, get the HORIZONTAL separation
double dclGetHorizontalSeparation(Point3D pos1, Point3D pos2);
// Given a position (lat/lon/elev), heading, vertical angle, and distance, calculate the new position.
// Assumes that the ground is not hit!!! Expects heading and angle in degrees, distance in meters.
Point3D dclUpdatePosition(Point3D pos, double heading, double angle, double distance);