struct OrbElements theSun,
struct fgTIME t, int idx)
{
- struct CelestialCoord
- result;
+ struct CelestialCoord result;
- struct SunPos
- SolarPosition;
+ fgSUNPOS SolarPosition;
- double
- eccAnom, r, v, ecl, actTime, R, s, ir, Nr, B, FV, ring_magn,
+ double eccAnom, r, v, ecl, actTime, R, s, ir, Nr, B, FV, ring_magn,
xv, yv, xh, yh, zh, xg, yg, zg, xe, ye, ze;
- actTime = fgCalcActTime(t);
- /* calculate the angle between ecliptic and equatorial coordinate system */
- /* ecl = DEG_TO_RAD * (23.4393 - 3.563E-7 * actTime); */
- ecl = 0.409093 - 6.2186E-9 * actTime;
+ actTime = fgCalcActTime(t);
+ /*calculate the angle between ecliptic and equatorial coordinate system */
+ ecl = DEG_TO_RAD * (23.4393 - 3.563E-7 * actTime);
/* calculate the eccentric anomaly */
- eccAnom = fgCalcEccAnom(planet.M, planet.e);
+ eccAnom = fgCalcEccAnom(planet.M, planet.e);
/* calculate the planets distance (r) and true anomaly (v) */
xv = planet.a * (cos(eccAnom) - planet.e);
yv = planet.a * (sqrt(1.0 - planet.e*planet.e) * sin(eccAnom));
v = atan2(yv, xv);
r = sqrt ( xv*xv + yv*yv);
-
+
/* calculate the planets position in 3-dimensional space */
- xh = r * ( cos(planet.N) * cos(v+planet.w) - sin(planet.N) * sin(v+planet.w) * cos(planet.i));
- yh = r * ( sin(planet.N) * cos(v+planet.w) + cos(planet.N) * sin(v+planet.w) * cos(planet.i));
+ xh = r * (cos (planet.N) * cos (v + planet.w) -
+ sin (planet.N) * sin (v + planet.w) * cos (planet.i));
+ yh = r * (sin (planet.N) * cos (v + planet.w) +
+ cos (planet.N) * sin (v + planet.w) * cos (planet.i));
zh = r * ( sin(v+planet.w) * sin(planet.i));
/* calculate the ecliptic longitude and latitude */
- /*
- lonecl = atan2(yh, xh);
- latecl = atan2(zh, sqrt ( xh*xh + yh*yh));
- */
- /* calculate the solar position */
-
- SolarPosition = fgCalcSunPos(theSun);
- xg = xh + SolarPosition.xs;
- yg = yh + SolarPosition.ys;
+ xg = xh + solarPosition.xs;
+ yg = yh + solarPosition.ys;
zg = zh;
xe = xg;
result.RightAscension = atan2(ye,xe);
result.Declination = atan2(ze, sqrt(xe*xe + ye*ye));
-
/* Let's calculate the brightness of the planet */
R = sqrt ( xg*xg + yg*yg + zg*zg);
ir = 0.4897394;
Nr = 2.9585076 + 6.6672E-7*actTime;
- B = asin ( sin (result.Declination) * cos(ir) - cos(result.Declination) * sin (ir) * sin (result.RightAscension - Nr));
+ B = asin (sin (result.Declination) * cos (ir) -
+ cos (result.Declination) * sin (ir) *
+ sin (result.RightAscension - Nr));
ring_magn = -2.6 * sin (fabs(B)) + 1.2 * pow(sin(B),2);
result.magnitude = -9.0 + 5*log10( r*R ) + 0.044 * FV + ring_magn;
break;
fgPrintf( FG_ASTRO, FG_ALERT, "index %d out of range !!!!\n", idx);
}
fgPrintf( FG_ASTRO, FG_DEBUG,
- " Planet found at %f (ra), %f (dec)\n",
+ " Planet found at %f (ra), %f (dec)\n",
result.RightAscension, result.Declination);
fgPrintf( FG_ASTRO, FG_DEBUG,
" Geocentric dist %f\n"
void fgPlanetsInit( void )
{
+ struct fgLIGHT *l;
int i;
struct CelestialCoord pltPos;
double magnitude;
+ l = &cur_light_params;
/* if the display list was already built during a previous init,
- recycle it */
+ then recycle it */
- if (planets)
+ if (planets) {
xglDeleteLists(planets, 1);
+ }
planets = xglGenLists(1);
xglNewList( planets, GL_COMPILE );
pltPos = fgCalculatePlanet(pltOrbElements[i],
pltOrbElements[0], cur_time_params, i);
- /* give the planets a temporary color, for testing purposes */
- /* xglColor3f( 1.0, 0.0, 0.0); */
- /* scale magnitudes to (0.0 - 1.0) */
-
magnitude = (0.0 - pltPos.magnitude) / 5.0 + 1.0;
/* scale magnitudes again so they look ok */
if ( magnitude > 1.0 ) { magnitude = 1.0; }
if ( magnitude < 0.0 ) { magnitude = 0.0; }
-
- xglColor3f(magnitude, magnitude, magnitude);
- /* xglColor3f(1.0, 1.0,1.0); */
-
- xglVertex3f( 50000.0 * cos(pltPos.RightAscension) *
- cos(pltPos.Declination),
- 50000.0 * sin(pltPos.RightAscension) *
- cos(pltPos.Declination),
- 50000.0 * sin(pltPos.Declination) );
+ /* Add planets to the display list, based on sun_angle and current
+ magnitude It's pretty experimental... */
+
+ if ((double) (l->sun_angle - FG_PI_2) >
+ ((magnitude - 1.0) * -20 * DEG_TO_RAD))
+ {
+ xglColor3f (magnitude, magnitude, magnitude);
+ printf ("Sun Angle to Horizon (in Rads) = %f\n",
+ (double) (l->sun_angle - FG_PI_2));
+ printf ("Transformed Magnitude is :%f %f\n",
+ magnitude, (magnitude - 1.0) * -20 * DEG_TO_RAD);
+
+ xglVertex3f (50000.0 * cos (pltPos.RightAscension) *
+ cos (pltPos.Declination),
+ 50000.0 * sin (pltPos.RightAscension) *
+ cos (pltPos.Declination),
+ 50000.0 * sin (pltPos.Declination));
+ }
}
xglEnd();
xglEndList();
/* $Log$
-/* Revision 1.5 1998/02/03 23:20:12 curt
-/* Lots of little tweaks to fix various consistency problems discovered by
-/* Solaris' CC. Fixed a bug in fg_debug.c with how the fgPrintf() wrapper
-/* passed arguments along to the real printf(). Also incorporated HUD changes
-/* by Michele America.
+/* Revision 1.7 1998/02/23 19:07:55 curt
+/* Incorporated Durk's Astro/ tweaks. Includes unifying the sun position
+/* calculation code between sun display, and other FG sections that use this
+/* for things like lighting.
/*
+ * Revision 1.6 1998/02/12 21:59:36 curt
+ * Incorporated code changes contributed by Charlie Hotchkiss
+ * <chotchkiss@namg.us.anritsu.com>
+ *
+ * Revision 1.5 1998/02/03 23:20:12 curt
+ * Lots of little tweaks to fix various consistency problems discovered by
+ * Solaris' CC. Fixed a bug in fg_debug.c with how the fgPrintf() wrapper
+ * passed arguments along to the real printf(). Also incorporated HUD changes
+ * by Michele America.
+ *
* Revision 1.4 1998/02/02 20:53:23 curt
* To version 0.29
*