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Various "inline" code optimizations contributed by Norman Vine.

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This commit is contained in:
curt
1998-08-24 20:04:08 +00:00
parent dacc051a57
commit aef484d5fc
7 changed files with 225 additions and 43 deletions
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Math/polar3d.cxx
+42 -6
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@@ -37,9 +37,12 @@
* to be specified in meters */
fgPoint3d fgPolarToCart3d(fgPoint3d p) {
fgPoint3d pnew;
double tmp;
pnew.x = cos(p.lon) * cos(p.lat) * p.radius;
pnew.y = sin(p.lon) * cos(p.lat) * p.radius;
tmp = cos(p.lat) * p.radius;
pnew.x = cos(p.lon) * tmp;
pnew.y = sin(p.lon) * tmp;
pnew.z = sin(p.lat) * p.radius;
return(pnew);
@@ -61,12 +64,45 @@ fgPoint3d fgCartToPolar3d(fgPoint3d cp) {
}
/* Find the Altitude above the Ellipsoid (WGS84) given the Earth
* Centered Cartesian coordinate vector Distances are specified in
* meters. */
double fgGeodAltFromCart(fgPoint3d cp)
{
double t_lat, x_alpha, mu_alpha;
double lat_geoc, radius;
double result;
lat_geoc = FG_PI_2 - atan2( sqrt(cp.x*cp.x + cp.y*cp.y), cp.z );
radius = sqrt(cp.x*cp.x + cp.y*cp.y + cp.z*cp.z);
if( ( (FG_PI_2 - lat_geoc) < ONE_SECOND ) /* near North pole */
|| ( (FG_PI_2 + lat_geoc) < ONE_SECOND ) ) /* near South pole */
{
result = radius - EQUATORIAL_RADIUS_M*E;
} else {
t_lat = tan(lat_geoc);
x_alpha = E*EQUATORIAL_RADIUS_M/sqrt(t_lat*t_lat + E*E);
mu_alpha = atan2(sqrt(RESQ_M - x_alpha*x_alpha),E*x_alpha);
if (lat_geoc < 0) {
mu_alpha = - mu_alpha;
}
result = (radius - x_alpha/cos(lat_geoc))*cos(mu_alpha - lat_geoc);
}
return(result);
}
/* $Log$
/* Revision 1.1 1998/07/08 14:40:08 curt
/* polar3d.[ch] renamed to polar3d.[ch]xx, vector.[ch] renamed to vector.[ch]xx
/* Updated fg_geodesy comments to reflect that routines expect and produce
/* meters.
/* Revision 1.2 1998/08/24 20:04:11 curt
/* Various "inline" code optimizations contributed by Norman Vine.
/*
* Revision 1.1 1998/07/08 14:40:08 curt
* polar3d.[ch] renamed to polar3d.[ch]xx, vector.[ch] renamed to vector.[ch]xx
* Updated fg_geodesy comments to reflect that routines expect and produce
* meters.
*
* Revision 1.2 1998/05/03 00:45:49 curt
* Commented out a debugging printf.
*