From b5cf8b7323fb3c789c91442387bccb5b4452eea5 Mon Sep 17 00:00:00 2001
From: curt <curt>
Date: Tue, 15 Sep 1998 04:27:49 +0000
Subject: [PATCH] Changes for new astro code.

---
 Time/fg_time.cxx | 11 ++++++++---
 Time/sunpos.cxx  | 30 ++++++++++++++++++++++++++----
 2 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/Time/fg_time.cxx b/Time/fg_time.cxx
index d75517be1..eb321c9b2 100644
--- a/Time/fg_time.cxx
+++ b/Time/fg_time.cxx
@@ -42,9 +42,10 @@
 #  include <sys/time.h>  // for get/setitimer, gettimeofday, struct timeval
 #endif
 
-#include <Astro/orbits.hxx>
-#include <Astro/sun.hxx>
+//#include <Astro/orbits.hxx>
+//#include <Astro/sun.hxx>
 #include <Astro/sky.hxx>
+#include <Astro/solarsystem.hxx>
 #include <Debug/fg_debug.h>
 #include <Flight/flight.h>
 #include <Include/fg_constants.h>
@@ -66,7 +67,8 @@ fgTIME cur_time_params;
 
 // Force an update of the sky and lighting parameters
 static void local_update_sky_and_lighting_params( void ) {
-    fgSunInit();
+    // fgSunInit();
+    SolarSystem::theSolarSystem->rebuild();
     cur_light_params.Update();
     fgSkyColorsInit();
 }
@@ -425,6 +427,9 @@ void fgTimeUpdate(fgFLIGHT *f, fgTIME *t) {
 
 
 // $Log$
+// Revision 1.17  1998/09/15 04:27:49  curt
+// Changes for new astro code.
+//
 // Revision 1.16  1998/08/29 13:11:32  curt
 // Bernie Bright writes:
 //   I've created some new classes to enable pointers-to-functions and
diff --git a/Time/sunpos.cxx b/Time/sunpos.cxx
index 2b746ca78..af40285cd 100644
--- a/Time/sunpos.cxx
+++ b/Time/sunpos.cxx
@@ -43,7 +43,8 @@
 #include <stdio.h>
 #include <time.h>
 
-#include <Astro/orbits.hxx>
+//#include <Astro/orbits.hxx>
+#include <Astro/solarsystem.hxx>
 #include <Include/fg_constants.h>
 #include <Main/views.hxx>
 #include <Math/fg_geodesy.h>
@@ -55,6 +56,7 @@
 #include "fg_time.hxx"
 #include "sunpos.hxx"
 
+extern SolarSystem *solarSystem;
 
 #undef E
 
@@ -255,8 +257,23 @@ void fgSunPosition(time_t ssue, double *lon, double *lat) {
 
     /* lambda = sun_ecliptic_longitude(ssue); */
     /* ecliptic_to_equatorial(lambda, 0.0, &alpha, &delta); */
-    ecliptic_to_equatorial (solarPosition.lonSun, 0.0, &alpha, &delta);
-
+    //ecliptic_to_equatorial (solarPosition.lonSun, 0.0, &alpha, &delta);
+    
+    /* ********************************************************************** 
+     * NOTE: in the next function, each time the sun's position is updated, the
+     * the sun's longitude is returned from solarSystem->sun. Note that the 
+     * sun's position is updated at a much higher frequency than the rate at 
+     * which the solar system's rebuilds occur. This is not a problem, however,
+     * because the fgSunPosition we're talking about here concerns the changing
+     * position of the sun due to the daily rotation of the earth.
+     * The ecliptic longitude, however, represents the position of the sun with
+     * respect to the stars, and completes just one cycle over the course of a 
+     * year. Its therefore pretty safe to update the sun's longitude only once
+     * every ten minutes. (Comment added by Durk Talsma).
+     ************************************************************************/
+
+    ecliptic_to_equatorial( SolarSystem::theSolarSystem->getSun()->getLon(),
+			    0.0, &alpha, &delta );
     tmp = alpha - (FG_2PI/24)*GST(ssue);
     if (tmp < -FG_PI) {
 	do tmp += FG_2PI;
@@ -286,7 +303,9 @@ static void fgSunPositionGST(double gst, double *lon, double *lat) {
 
     /* lambda = sun_ecliptic_longitude(ssue); */
     /* ecliptic_to_equatorial(lambda, 0.0, &alpha, &delta); */
-    ecliptic_to_equatorial (solarPosition.lonSun, 0.0, &alpha, &delta);
+    //ecliptic_to_equatorial (solarPosition.lonSun, 0.0, &alpha, &delta);
+    ecliptic_to_equatorial( SolarSystem::theSolarSystem->getSun()->getLon(),
+			    0.0, &alpha,  &delta );
 
 //    tmp = alpha - (FG_2PI/24)*GST(ssue);
     tmp = alpha - (FG_2PI/24)*gst;	
@@ -404,6 +423,9 @@ void fgUpdateSunPos( void ) {
 
 
 // $Log$
+// Revision 1.12  1998/09/15 04:27:50  curt
+// Changes for new astro code.
+//
 // Revision 1.11  1998/08/12 21:13:22  curt
 // Optimizations by Norman Vine.
 //
-- 
2.39.2