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Expose aircraft-relative offset to Nasal.

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This allows easily computing offsets in aircraft-relative coordinates,
and converting to global cartesian (ECEF) reference frame.
This commit is contained in:
James Turner 2017-02-02 17:54:18 +01:00
parent 9c3697e16d
commit d13a672698
1 changed files with 38 additions and 14 deletions
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52
src/Scripting/NasalPositioned.cxx
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@ -1010,29 +1010,52 @@ static naRef f_get_cart_ground_intersection(naContext c, naRef me, int argc, naR
naRuntimeError(c, "geod_hash get_cart_ground_intersection(position: hash{x,y,z}, direction:hash{x,y,z}) expects argument(1) to be hash of direction containing x,y,z");
SGVec3d nearestHit;
if (!globals->get_scenery()->get_cart_ground_intersection(pos, dir, nearestHit))
return naNil();
double xyz[3];
xyz[0] = nearestHit[0];
xyz[1] = nearestHit[1];
xyz[2] = nearestHit[2];
double lat_rad, lon_rad, alt_m;
sgCartToGeod(xyz, &lat_rad, &lon_rad, &alt_m);
double lat_deg = lat_rad * SG_RADIANS_TO_DEGREES;
double lon_deg = lon_rad * SG_RADIANS_TO_DEGREES;
const SGGeod geodHit = SGGeod::fromCart(nearestHit);
// build a hash for returned intersection
naRef intersection_h = naNewHash(c);
hashset(c, intersection_h, "lat", naNum(lat_deg));
hashset(c, intersection_h, "lon", naNum(lon_deg));
hashset(c, intersection_h, "elevation", naNum(alt_m));
hashset(c, intersection_h, "lat", naNum(geodHit.getLatitudeDeg()));
hashset(c, intersection_h, "lon", naNum(geodHit.getLongitudeDeg()));
hashset(c, intersection_h, "elevation", naNum(geodHit.getElevationM()));
return intersection_h;
}
// convert from aircraft reference frame to global (ECEF) cartesian
static naRef f_aircraftToCart(naContext c, naRef me, int argc, naRef* args)
{
if (argc != 1)
naRuntimeError(c, "hash{x,y,z} aircraftToCart(position: hash{x,y,z}) expects one argument");
SGVec3d offset;
if (!vec3dFromHash(args[0], offset))
naRuntimeError(c, "aircraftToCart expects argument(0) to be a hash containing x,y,z");
double heading, pitch, roll;
globals->get_aircraft_orientation(heading, pitch, roll);
// Transform that one to the horizontal local coordinate system.
SGQuatd hlTrans = SGQuatd::fromLonLat(globals->get_aircraft_position());
// post-rotate the orientation of the aircraft wrt the horizontal local frame
hlTrans *= SGQuatd::fromYawPitchRollDeg(heading, pitch, roll);
// The offset converted to the usual body fixed coordinate system
// rotated to the earth fiexed coordinates axis
offset = hlTrans.backTransform(offset);
SGVec3d v = globals->get_aircraft_position_cart() + offset;
// build a hash for returned location
naRef pos_h = naNewHash(c);
hashset(c, pos_h, "x", naNum(v.x()));
hashset(c, pos_h, "y", naNum(v.y()));
hashset(c, pos_h, "z", naNum(v.z()));
return pos_h;
}
// For given geodetic point return array with elevation, and a material data
// hash, or nil if there's no information available (tile not loaded). If
// information about the material isn't available, then nil is returned instead
@ -2563,6 +2586,7 @@ static struct { const char* name; naCFunction func; } funcs[] = {
{ "geodtocart", f_geodtocart },
{ "geodinfo", f_geodinfo },
{ "get_cart_ground_intersection", f_get_cart_ground_intersection },
{ "aircraftToCart", f_aircraftToCart },
{ "airportinfo", f_airportinfo },
{ "findAirportsWithinRange", f_findAirportsWithinRange },
{ "findAirportsByICAO", f_findAirportsByICAO },