From: curt <curt>
Date: Thu, 2 Mar 2000 12:51:30 +0000 (+0000)
Subject: Working on separating out ephemeris code from the actual rendering code
X-Git-Url: https://git.mxchange.org/?a=commitdiff_plain;h=a8db14196ace7a27aa09cda0b4f428ec40103202;p=simgear.git

Working on separating out ephemeris code from the actual rendering code
which I am trying to ssg-ify at the same time.
---

diff --git a/simgear/ephemeris/Makefile.am b/simgear/ephemeris/Makefile.am
index 849aa22c..3c67a015 100644
--- a/simgear/ephemeris/Makefile.am
+++ b/simgear/ephemeris/Makefile.am
@@ -2,6 +2,7 @@ noinst_LIBRARIES = libAstro.a
 
 libAstro_a_SOURCES = \
 	celestialBody.cxx celestialBody.hxx \
+	ephemeris.cxx ephemeris.hxx \
 	jupiter.cxx jupiter.hxx \
 	mars.cxx mars.hxx \
 	mercury.cxx mercury.hxx \
diff --git a/simgear/ephemeris/celestialBody.hxx b/simgear/ephemeris/celestialBody.hxx
index 410ca01a..59611ef4 100644
--- a/simgear/ephemeris/celestialBody.hxx
+++ b/simgear/ephemeris/celestialBody.hxx
@@ -39,8 +39,8 @@ class Star;
 
 class CelestialBody
 {
-protected:              // make the data protected, in order to give the inherited
-                        // classes direct access to the data
+protected:              // make the data protected, in order to give the
+                        //  inherited classes direct access to the data
   double NFirst;       	/* longitude of the ascending node first part */
   double NSec;		/* longitude of the ascending node second part */
   double iFirst;       	/* inclination to the ecliptic first part */
@@ -72,8 +72,17 @@ public:
 		double af, double as,
 		double ef, double es,
 		double Mf, double Ms, FGTime *t);
+  CelestialBody(double Nf, double Ns,
+		double If, double Is,
+		double wf, double ws,
+		double af, double as,
+		double ef, double es,
+		double Mf, double Ms);
   void getPos(double *ra, double *dec);
   void getPos(double *ra, double *dec, double *magnitude);
+  double getRightAscension();
+  double getDeclination();
+  double getMagnitude();
   double getLon();
   double getLat(); 
   void updatePosition(FGTime *t, Star *ourSun);
@@ -115,6 +124,21 @@ inline CelestialBody::CelestialBody(double Nf, double Ns,
   updateOrbElements(t);
 };
 
+inline CelestialBody::CelestialBody(double Nf, double Ns,
+				    double If, double Is,
+				    double wf, double ws,
+				    double af, double as,
+				    double ef, double es,
+				    double Mf, double Ms)
+{
+  NFirst = Nf;     NSec = Ns;
+  iFirst = If;     iSec = Is;
+  wFirst = wf;     wSec = ws;
+  aFirst = af;     aSec = as;
+  eFirst = ef;     eSec = es;
+  MFirst = Mf;     MSec = Ms;
+};
+
 /****************************************************************************
  * inline void CelestialBody::updateOrbElements(FGTime *t)
  * given the current time, this private member calculates the actual 
@@ -171,6 +195,10 @@ inline void CelestialBody::getPos(double* ra, double* dec, double* magn)
   *magn = magnitude;
 }
 
+inline double CelestialBody::getRightAscension() { return rightAscension; }
+inline double CelestialBody::getDeclination() { return declination; }
+inline double CelestialBody::getMagnitude() { return magnitude; }
+
 inline double CelestialBody::getLon()
 {
   return lonEcl;
diff --git a/simgear/ephemeris/skydome.cxx b/simgear/ephemeris/skydome.cxx
deleted file mode 100644
index f71f98bd..00000000
--- a/simgear/ephemeris/skydome.cxx
+++ /dev/null
@@ -1,814 +0,0 @@
-// skydome.cxx -- model sky with an upside down "bowl"
-//
-// Written by Curtis Olson, started December 1997.
-// SSG-ified by Curtis Olson, February 2000.
-//
-// Copyright (C) 1997-2000  Curtis L. Olson  - curt@flightgear.org
-//
-// This program is free software; you can redistribute it and/or
-// modify it under the terms of the GNU General Public License as
-// published by the Free Software Foundation; either version 2 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful, but
-// WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-// General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program; if not, write to the Free Software
-// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-//
-// $Id$
-
-
-#ifdef HAVE_CONFIG_H
-#  include <config.h>
-#endif
-
-#ifdef HAVE_WINDOWS_H
-#  include <windows.h>
-#endif
-
-#include <math.h>
-
-#include <GL/glut.h>
-#include <simgear/xgl/xgl.h>
-
-#include <simgear/constants.h>
-#include <simgear/debug/logstream.hxx>
-#include <simgear/math/fg_random.h>
-
-#include <Aircraft/aircraft.hxx>
-#include <FDM/flight.hxx>
-#include <Main/views.hxx>
-#include <Time/event.hxx>
-#include <Time/fg_time.hxx>
-
-#include "skydome.hxx"
-
-
-#ifdef __MWERKS__
-#  pragma global_optimizer off
-#endif
-
-
-// in meters of course
-#define CENTER_ELEV   25000.0
-
-#define UPPER_RADIUS  50000.0
-#define UPPER_ELEV    20000.0
-
-#define MIDDLE_RADIUS 70000.0
-#define MIDDLE_ELEV    8000.0
-
-#define LOWER_RADIUS  80000.0
-#define LOWER_ELEV        0.0
-
-#define BOTTOM_RADIUS 50000.0
-#define BOTTOM_ELEV   -2000.0
-
-
-// static float inner_vertex[12][3];
-// static float middle_vertex[12][3];
-// static float outer_vertex[12][3];
-// static float bottom_vertex[12][3];
-
-// static GLubyte upper_color[12][4];
-// static GLubyte middle_color[12][4];
-// static GLubyte lower_color[12][4];
-
-
-// Defined the shared sky object here
-FGSkyDome current_sky;
-
-
-// Constructor
-FGSkyDome::FGSkyDome( void ) {
-}
-
-
-// Destructor
-FGSkyDome::~FGSkyDome( void ) {
-}
-
-
-// initialize the sky object and connect it into the scene graph
-bool FGSkyDome::initialize( ssgRoot *root ) {
-    sgVec3 color;
-
-    float theta;
-    int i;
-
-    // set up the state
-    sky_state = new ssgSimpleState();
-    if ( current_options.get_shading() == 1 ) {
-	sky_state->setShadeModel( GL_SMOOTH );
-    } else {
-	sky_state->setShadeModel( GL_FLAT );
-    }
-    sky_state->disable( GL_LIGHTING );
-    sky_state->disable( GL_DEPTH_TEST );
-    sky_state->disable( GL_CULL_FACE );
-    sky_state->disable( GL_TEXTURE );
-    sky_state->enable( GL_COLOR_MATERIAL );
-    sky_state->setColourMaterial( GL_AMBIENT_AND_DIFFUSE );
-
-    // initialize arrays
-    center_disk_vl = new ssgVertexArray( 14 );
-    center_disk_cl = new ssgColourArray( 14 );
-				       
-    upper_ring_vl = new ssgVertexArray( 26 );
-    upper_ring_cl = new ssgColourArray( 26 );
-
-    middle_ring_vl = new ssgVertexArray( 26 );
-    middle_ring_cl = new ssgColourArray( 26 );
-
-    lower_ring_vl = new ssgVertexArray( 26 );
-    lower_ring_cl = new ssgColourArray( 26 );
-
-    // initially seed to all blue
-    sgSetVec3( color, 0.0, 0.0, 1.0 );
-
-    // generate the raw vertex data
-    sgVec3 center_vertex;
-    sgVec3 upper_vertex[12];
-    sgVec3 middle_vertex[12];
-    sgVec3 lower_vertex[12];
-    sgVec3 bottom_vertex[12];
-
-    sgSetVec3( center_vertex, 0.0, 0.0, CENTER_ELEV );
-
-    for ( i = 0; i < 12; i++ ) {
-	theta = (i * 30.0) * DEG_TO_RAD;
-
-	sgSetVec3( upper_vertex[i],
-		   cos(theta) * UPPER_RADIUS,
-		   sin(theta) * UPPER_RADIUS,
-		   UPPER_ELEV );
-	
-	sgSetVec3( middle_vertex[i],
-		   cos((double)theta) * MIDDLE_RADIUS,
-		   sin((double)theta) * MIDDLE_RADIUS,
-		   MIDDLE_ELEV );
-
-	sgSetVec3( lower_vertex[i],
-		   cos((double)theta) * LOWER_RADIUS,
-		   sin((double)theta) * LOWER_RADIUS,
-		   LOWER_ELEV );
-
-	sgSetVec3( bottom_vertex[i],
-		   cos((double)theta) * BOTTOM_RADIUS,
-		   sin((double)theta) * BOTTOM_RADIUS,
-		   BOTTOM_ELEV );
-    }
-
-    // generate the center disk vertex/color arrays
-    center_disk_vl->add( center_vertex );
-    center_disk_cl->add( color );
-    for ( i = 11; i >= 0; i-- ) {
-	center_disk_vl->add( upper_vertex[i] );
-	center_disk_cl->add( color );
-    }
-    center_disk_vl->add( upper_vertex[11] );
-    center_disk_cl->add( color );
-
-    // generate the upper ring
-    for ( i = 0; i < 12; i++ ) {
-	upper_ring_vl->add( middle_vertex[i] );
-	upper_ring_cl->add( color );
-
-	upper_ring_vl->add( upper_vertex[i] );
-	upper_ring_cl->add( color );
-    }
-    upper_ring_vl->add( middle_vertex[0] );
-    upper_ring_cl->add( color );
-
-    upper_ring_vl->add( upper_vertex[0] );
-    upper_ring_cl->add( color );
-
-    // generate middle ring
-    for ( i = 0; i < 12; i++ ) {
-	middle_ring_vl->add( lower_vertex[i] );
-	middle_ring_cl->add( color );
-
-	middle_ring_vl->add( middle_vertex[i] );
-	middle_ring_cl->add( color );
-    }
-    middle_ring_vl->add( lower_vertex[0] );
-    middle_ring_cl->add( color );
-
-    middle_ring_vl->add( middle_vertex[0] );
-    middle_ring_cl->add( color );
-
-    // generate lower ring
-    for ( i = 0; i < 12; i++ ) {
-	lower_ring_vl->add( bottom_vertex[i] );
-	lower_ring_cl->add( color );
-
-	lower_ring_vl->add( lower_vertex[i] );
-	lower_ring_cl->add( color );
-    }
-    lower_ring_vl->add( bottom_vertex[0] );
-    lower_ring_cl->add( color );
-
-    lower_ring_vl->add( lower_vertex[0] );
-    lower_ring_cl->add( color );
-
-    // force a repaint of the sky colors with ugly defaults
-    sgVec3 fog_color;
-    sgSetVec3( fog_color, 1.0, 1.0, 1.0 );
-    repaint( color, fog_color, 0.0 );
-
-    // build the ssg scene graph sub tree for the sky and connected
-    // into the provide scene graph branch
-    sky_selector = new ssgSelector;
-    sky_transform = new ssgTransform;
-
-    ssgVtxTable *center_disk, *upper_ring, *middle_ring, *lower_ring;
-
-    center_disk = new ssgVtxTable( GL_TRIANGLE_FAN, 
-				   center_disk_vl, NULL, NULL, center_disk_cl );
-
-    upper_ring = new ssgVtxTable( GL_TRIANGLE_STRIP, 
-				  upper_ring_vl, NULL, NULL, upper_ring_cl );
-
-    middle_ring = new ssgVtxTable( GL_TRIANGLE_STRIP, 
-				   middle_ring_vl, NULL, NULL, middle_ring_cl );
-
-    lower_ring = new ssgVtxTable( GL_TRIANGLE_STRIP, 
-				  lower_ring_vl, NULL, NULL, lower_ring_cl );
-
-    center_disk->setState( sky_state );
-    upper_ring->setState( sky_state );
-    middle_ring->setState( sky_state );
-    lower_ring->setState( sky_state );
-
-    sky_transform->addKid( center_disk );
-    sky_transform->addKid( upper_ring );
-    sky_transform->addKid( middle_ring );
-    sky_transform->addKid( lower_ring );
-
-    sky_selector->addKid( sky_transform );
-    sky_selector->clrTraversalMaskBits( SSGTRAV_HOT );
-
-    root->addKid( sky_selector );
-
-    return true;
-}
-
-
-// repaint the sky colors based on current value of sun_angle, sky,
-// and fog colors.  This updates the color arrays for ssgVtxTable.
-// sun angle in degrees relative to verticle
-// 0 degrees = high noon
-// 90 degrees = sun rise/set
-// 180 degrees = darkest midnight
-bool FGSkyDome::repaint( sgVec3 sky_color, sgVec3 fog_color, double sun_angle ) {
-    double diff;
-    sgVec3 outer_param, outer_amt, outer_diff;
-    sgVec3 middle_param, middle_amt, middle_diff;
-    int i, j;
-
-    // Check for sunrise/sunset condition
-    if ( (sun_angle > 80.0) && (sun_angle < 100.0) ) {
-	// 0.0 - 0.4
-	sgSetVec3( outer_param,
-		   (10.0 - fabs(90.0 - sun_angle)) / 20.0,
-		   (10.0 - fabs(90.0 - sun_angle)) / 40.0,
-		   -(10.0 - fabs(90.0 - sun_angle)) / 30.0 );
-
-	sgSetVec3( middle_param,
-		   (10.0 - fabs(90.0 - sun_angle)) / 40.0,
-		   (10.0 - fabs(90.0 - sun_angle)) / 80.0,
-		   0.0 );
-
-	sgScaleVec3( outer_diff, outer_param, 1.0 / 6.0 );
-
-	sgScaleVec3( middle_diff, middle_param, 1.0 / 6.0 );
-    } else {
-	sgSetVec3( outer_param, 0.0, 0.0, 0.0 );
-	sgSetVec3( middle_param, 0.0, 0.0, 0.0 );
-
-	sgSetVec3( outer_diff, 0.0, 0.0, 0.0 );
-	sgSetVec3( middle_diff, 0.0, 0.0, 0.0 );
-    }
-    // printf("  outer_red_param = %.2f  outer_red_diff = %.2f\n", 
-    //        outer_red_param, outer_red_diff);
-
-    // calculate transition colors between sky and fog
-    sgCopyVec3( outer_amt, outer_param );
-    sgCopyVec3( middle_amt, middle_param );
-
-    //
-    // First, recalulate the basic colors
-    //
-
-    sgVec3 upper_color[12];
-    sgVec3 middle_color[12];
-    sgVec3 lower_color[12];
-    sgVec3 bottom_color[12];
-
-    for ( i = 0; i < 6; i++ ) {
-	for ( j = 0; j < 3; j++ ) {
-	    diff = sky_color[j] - fog_color[j];
-
-	    // printf("sky = %.2f  fog = %.2f  diff = %.2f\n", 
-	    //        l->sky_color[j], l->fog_color[j], diff);
-
-	    upper_color[i][j] = sky_color[j] - diff * 0.3;
-	    middle_color[i][j] = sky_color[j] - diff * 0.9 + middle_amt[j];
-	    lower_color[i][j] = fog_color[j] + outer_amt[j];
-
-	    if ( upper_color[i][j] > 1.0 ) { upper_color[i][j] = 1.0; }
-	    if ( upper_color[i][j] < 0.1 ) { upper_color[i][j] = 0.1; }
-	    if ( middle_color[i][j] > 1.0 ) { middle_color[i][j] = 1.0; }
-	    if ( middle_color[i][j] < 0.1 ) { middle_color[i][j] = 0.1; }
-	    if ( lower_color[i][j] > 1.0 ) { lower_color[i][j] = 1.0; }
-	    if ( lower_color[i][j] < 0.1 ) { lower_color[i][j] = 0.1; }
-	}
-	// upper_color[i][3] = middle_color[i][3] = lower_color[i][3] = 
-	//                     (GLubyte)(sky_color[3] * 1.0);
-
-	for ( j = 0; j < 3; j++ ) {
-	    outer_amt[j] -= outer_diff[j];
-	    middle_amt[j] -= middle_diff[j];
-	}
-
-	/*
-	printf("upper_color[%d] = %.2f %.2f %.2f %.2f\n", i, upper_color[i][0],
-	       upper_color[i][1], upper_color[i][2], upper_color[i][3]);
-	printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i, 
-	       middle_color[i][0], middle_color[i][1], middle_color[i][2], 
-	       middle_color[i][3]);
-	printf("lower_color[%d] = %.2f %.2f %.2f %.2f\n", i, 
-	       lower_color[i][0], lower_color[i][1], lower_color[i][2], 
-	       lower_color[i][3]);
-	*/
-    }
-
-    sgSetVec3( outer_amt, 0.0, 0.0, 0.0 );
-    sgSetVec3( middle_amt, 0.0, 0.0, 0.0 );
-
-    for ( i = 6; i < 12; i++ ) {
-	for ( j = 0; j < 3; j++ ) {
-	    diff = sky_color[j] - fog_color[j];
-
-	    // printf("sky = %.2f  fog = %.2f  diff = %.2f\n", 
-	    //        sky_color[j], fog_color[j], diff);
-
-	    upper_color[i][j] = sky_color[j] - diff * 0.3;
-	    middle_color[i][j] = sky_color[j] - diff * 0.9 + middle_amt[j];
-	    lower_color[i][j] = fog_color[j] + outer_amt[j];
-
-	    if ( upper_color[i][j] > 1.0 ) { upper_color[i][j] = 1.0; }
-	    if ( upper_color[i][j] < 0.1 ) { upper_color[i][j] = 0.1; }
-	    if ( middle_color[i][j] > 1.0 ) { middle_color[i][j] = 1.0; }
-	    if ( middle_color[i][j] < 0.1 ) { middle_color[i][j] = 0.1; }
-	    if ( lower_color[i][j] > 1.0 ) { lower_color[i][j] = 1.0; }
-	    if ( lower_color[i][j] < 35 ) { lower_color[i][j] = 35; }
-	}
-	// upper_color[i][3] = middle_color[i][3] = lower_color[i][3] = 
-	//                     (GLubyte)(sky_color[3] * 1.0);
-
-	for ( j = 0; j < 3; j++ ) {
-	    outer_amt[j] += outer_diff[j];
-	    middle_amt[j] += middle_diff[j];
-	}
-
-	/*
-	printf("upper_color[%d] = %.2f %.2f %.2f %.2f\n", i, upper_color[i][0],
-	       upper_color[i][1], upper_color[i][2], upper_color[i][3]);
-	printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i, 
-	       middle_color[i][0], middle_color[i][1], middle_color[i][2], 
-	       middle_color[i][3]);
-	printf("lower_color[%d] = %.2f %.2f %.2f %.2f\n", i, 
-	       lower_color[i][0], lower_color[i][1], lower_color[i][2], 
-	       lower_color[i][3]);
-	*/
-    }
-
-    for ( i = 0; i < 12; i++ ) {
-	sgCopyVec3( bottom_color[i], fog_color );
-    }
-
-    //
-    // Second, assign the basic colors to the object color arrays
-    //
-
-    float *slot;
-    int counter;
-
-    // update the center disk color arrays
-    counter = 0;
-    slot = center_disk_cl->get( counter++ );
-    // sgVec3 red;
-    // sgSetVec3( red, 1.0, 0.0, 0.0 );
-    sgCopyVec3( slot, sky_color );
-    for ( i = 11; i >= 0; i-- ) {
-	slot = center_disk_cl->get( counter++ );
-	sgCopyVec3( slot, upper_color[i] );
-    }
-    slot = center_disk_cl->get( counter++ );
-    sgCopyVec3( slot, upper_color[11] );
-
-    // generate the upper ring
-    counter = 0;
-    for ( i = 0; i < 12; i++ ) {
-	slot = upper_ring_cl->get( counter++ );
-	sgCopyVec3( slot, middle_color[i] );
-
-	slot = upper_ring_cl->get( counter++ );
-	sgCopyVec3( slot, upper_color[i] );
-    }
-    slot = upper_ring_cl->get( counter++ );
-    sgCopyVec3( slot, middle_color[0] );
-
-    slot = upper_ring_cl->get( counter++ );
-    sgCopyVec3( slot, upper_color[0] );
-
-    // generate middle ring
-    counter = 0;
-    for ( i = 0; i < 12; i++ ) {
-	slot = middle_ring_cl->get( counter++ );
-	sgCopyVec3( slot, lower_color[i] );
-
-	slot = middle_ring_cl->get( counter++ );
-	sgCopyVec3( slot, middle_color[i] );
-    }
-    slot = middle_ring_cl->get( counter++ );
-    sgCopyVec3( slot, lower_color[0] );
-
-    slot = middle_ring_cl->get( counter++ );
-    sgCopyVec3( slot, middle_color[0] );
-
-    // generate lower ring
-    counter = 0;
-    for ( i = 0; i < 12; i++ ) {
-	slot = lower_ring_cl->get( counter++ );
-	sgCopyVec3( slot, bottom_color[i] );
-
-	slot = lower_ring_cl->get( counter++ );
-	sgCopyVec3( slot, lower_color[i] );
-    }
-    slot = lower_ring_cl->get( counter++ );
-    sgCopyVec3( slot, bottom_color[0] );
-
-    slot = lower_ring_cl->get( counter++ );
-    sgCopyVec3( slot, lower_color[0] );
-
-    return true;
-}
-
-
-// reposition the sky at the specified origin and orientation
-// lon specifies a rotation about the Z axis
-// lat specifies a rotation about the new Y axis
-// spin specifies a rotation about the new Z axis (and orients the
-// sunrise/set effects
-bool FGSkyDome::reposition( sgVec3 p, double lon, double lat, double spin ) {
-    sgMat4 T, LON, LAT, SPIN;
-    sgVec3 axis;
-
-    // Translate to view position
-    // Point3D zero_elev = current_view.get_cur_zero_elev();
-    // xglTranslatef( zero_elev.x(), zero_elev.y(), zero_elev.z() );
-    sgMakeTransMat4( T, p );
-
-    // printf("  Translated to %.2f %.2f %.2f\n", 
-    //        zero_elev.x, zero_elev.y, zero_elev.z );
-
-    // Rotate to proper orientation
-    // printf("  lon = %.2f  lat = %.2f\n", FG_Longitude * RAD_TO_DEG,
-    //        FG_Latitude * RAD_TO_DEG);
-    // xglRotatef( f->get_Longitude() * RAD_TO_DEG, 0.0, 0.0, 1.0 );
-    sgSetVec3( axis, 0.0, 0.0, 1.0 );
-    sgMakeRotMat4( LON, lon * RAD_TO_DEG, axis );
-
-    // xglRotatef( 90.0 - f->get_Latitude() * RAD_TO_DEG, 0.0, 1.0, 0.0 );
-    sgSetVec3( axis, 0.0, 1.0, 0.0 );
-    sgMakeRotMat4( LAT, 90.0 - lat * RAD_TO_DEG, axis );
-
-    // xglRotatef( l->sun_rotation * RAD_TO_DEG, 0.0, 0.0, 1.0 );
-    sgSetVec3( axis, 0.0, 0.0, 1.0 );
-    sgMakeRotMat4( SPIN, spin * RAD_TO_DEG, axis );
-
-    sgMat4 TRANSFORM;
-
-    sgCopyMat4( TRANSFORM, T );
-    sgPreMultMat4( TRANSFORM, LON );
-    sgPreMultMat4( TRANSFORM, LAT );
-    sgPreMultMat4( TRANSFORM, SPIN );
-
-    sgCoord skypos;
-    sgSetCoord( &skypos, TRANSFORM );
-
-    sky_transform->setTransform( &skypos );
-
-    return true;
-}
-
-
-#if 0
-
-// depricated code from here to the end 
-
-
-// Calculate the sky structure vertices
-void fgSkyVerticesInit() {
-    float theta;
-    int i;
-
-    FG_LOG(FG_ASTRO, FG_INFO, "  Generating the sky dome vertices.");
-
-    for ( i = 0; i < 12; i++ ) {
-	theta = (i * 30.0) * DEG_TO_RAD;
-	
-	inner_vertex[i][0] = cos(theta) * UPPER_RADIUS;
-	inner_vertex[i][1] = sin(theta) * UPPER_RADIUS;
-	inner_vertex[i][2] = UPPER_ELEV;
-	
-	// printf("    %.2f %.2f\n", cos(theta) * UPPER_RADIUS, 
-	//        sin(theta) * UPPER_RADIUS);
-
-	middle_vertex[i][0] = cos((double)theta) * MIDDLE_RADIUS;
-	middle_vertex[i][1] = sin((double)theta) * MIDDLE_RADIUS;
-	middle_vertex[i][2] = MIDDLE_ELEV;
-	    
-	outer_vertex[i][0] = cos((double)theta) * LOWER_RADIUS;
-	outer_vertex[i][1] = sin((double)theta) * LOWER_RADIUS;
-	outer_vertex[i][2] = LOWER_ELEV;
-	    
-	bottom_vertex[i][0] = cos((double)theta) * BOTTOM_RADIUS;
-	bottom_vertex[i][1] = sin((double)theta) * BOTTOM_RADIUS;
-	bottom_vertex[i][2] = BOTTOM_ELEV;
-    }
-}
-
-
-// (Re)calculate the sky colors at each vertex
-void fgSkyColorsInit() {
-    fgLIGHT *l;
-    double sun_angle, diff;
-    double outer_param[3], outer_amt[3], outer_diff[3];
-    double middle_param[3], middle_amt[3], middle_diff[3];
-    int i, j;
-
-    l = &cur_light_params;
-
-    FG_LOG( FG_ASTRO, FG_INFO, 
-	    "  Generating the sky colors for each vertex." );
-
-    // setup for the possibility of sunset effects
-    sun_angle = l->sun_angle * RAD_TO_DEG;
-    // fgPrintf( FG_ASTRO, FG_INFO, 
-    //           "  Sun angle in degrees = %.2f\n", sun_angle);
-
-    if ( (sun_angle > 80.0) && (sun_angle < 100.0) ) {
-	// 0.0 - 0.4
-	outer_param[0] = (10.0 - fabs(90.0 - sun_angle)) / 20.0;
-	outer_param[1] = (10.0 - fabs(90.0 - sun_angle)) / 40.0;
-	outer_param[2] = -(10.0 - fabs(90.0 - sun_angle)) / 30.0;
-	// outer_param[2] = 0.0;
-
-	middle_param[0] = (10.0 - fabs(90.0 - sun_angle)) / 40.0;
-	middle_param[1] = (10.0 - fabs(90.0 - sun_angle)) / 80.0;
-	middle_param[2] = 0.0;
-
-	outer_diff[0] = outer_param[0] / 6.0;
-	outer_diff[1] = outer_param[1] / 6.0;
-	outer_diff[2] = outer_param[2] / 6.0;
-
-	middle_diff[0] = middle_param[0] / 6.0;
-	middle_diff[1] = middle_param[1] / 6.0;
-	middle_diff[2] = middle_param[2] / 6.0;
-    } else {
-	outer_param[0] = outer_param[1] = outer_param[2] = 0.0;
-	middle_param[0] = middle_param[1] = middle_param[2] = 0.0;
-
-	outer_diff[0] = outer_diff[1] = outer_diff[2] = 0.0;
-	middle_diff[0] = middle_diff[1] = middle_diff[2] = 0.0;
-    }
-    // printf("  outer_red_param = %.2f  outer_red_diff = %.2f\n", 
-    //        outer_red_param, outer_red_diff);
-
-    // calculate transition colors between sky and fog
-    for ( j = 0; j < 3; j++ ) {
-	outer_amt[j] = outer_param[j];
-	middle_amt[j] = middle_param[j];
-    }
-
-    for ( i = 0; i < 6; i++ ) {
-	for ( j = 0; j < 3; j++ ) {
-	    diff = l->sky_color[j] - l->fog_color[j];
-
-	    // printf("sky = %.2f  fog = %.2f  diff = %.2f\n", 
-	    //        l->sky_color[j], l->fog_color[j], diff);
-
-	    upper_color[i][j] = (GLubyte)((l->sky_color[j] - diff * 0.3) * 255);
-	    middle_color[i][j] = (GLubyte)((l->sky_color[j] - diff * 0.9 
-					   + middle_amt[j]) * 255);
-	    lower_color[i][j] = (GLubyte)((l->fog_color[j] + outer_amt[j]) 
-					  * 255);
-
-	    if ( upper_color[i][j] > 255 ) { upper_color[i][j] = 255; }
-	    if ( upper_color[i][j] < 25 ) { upper_color[i][j] = 25; }
-	    if ( middle_color[i][j] > 255 ) { middle_color[i][j] = 255; }
-	    if ( middle_color[i][j] < 25 ) { middle_color[i][j] = 25; }
-	    if ( lower_color[i][j] > 255 ) { lower_color[i][j] = 255; }
-	    if ( lower_color[i][j] < 25 ) { lower_color[i][j] = 25; }
-	}
-	upper_color[i][3] = middle_color[i][3] = lower_color[i][3] = 
-	    (GLubyte)(l->sky_color[3] * 255);
-
-	for ( j = 0; j < 3; j++ ) {
-	    outer_amt[j] -= outer_diff[j];
-	    middle_amt[j] -= middle_diff[j];
-	}
-
-	/*
-	printf("upper_color[%d] = %.2f %.2f %.2f %.2f\n", i, upper_color[i][0],
-	       upper_color[i][1], upper_color[i][2], upper_color[i][3]);
-	printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i, 
-	       middle_color[i][0], middle_color[i][1], middle_color[i][2], 
-	       middle_color[i][3]);
-	printf("lower_color[%d] = %.2f %.2f %.2f %.2f\n", i, 
-	       lower_color[i][0], lower_color[i][1], lower_color[i][2], 
-	       lower_color[i][3]);
-	*/
-    }
-
-    for ( j = 0; j < 3; j++ ) {
-	outer_amt[j] = 0.0;
-	middle_amt[j] = 0.0;
-    }
-
-    for ( i = 6; i < 12; i++ ) {
-
-	for ( j = 0; j < 3; j++ ) {
-	    diff = l->sky_color[j] - l->fog_color[j];
-
-	    // printf("sky = %.2f  fog = %.2f  diff = %.2f\n", 
-	    //        l->sky_color[j], l->fog_color[j], diff);
-
-	    upper_color[i][j] = (GLubyte)((l->sky_color[j] - diff * 0.3) * 255);
-	    middle_color[i][j] = (GLubyte)((l->sky_color[j] - diff * 0.9 
-					    + middle_amt[j]) * 255);
-	    lower_color[i][j] = (GLubyte)((l->fog_color[j] + outer_amt[j]) 
-					  * 255);
-
-	    if ( upper_color[i][j] > 255 ) { upper_color[i][j] = 255; }
-	    if ( upper_color[i][j] < 25 ) { upper_color[i][j] = 25; }
-	    if ( middle_color[i][j] > 255 ) { middle_color[i][j] = 255; }
-	    if ( middle_color[i][j] < 25 ) { middle_color[i][j] = 25; }
-	    if ( lower_color[i][j] > 255 ) { lower_color[i][j] = 255; }
-	    if ( lower_color[i][j] < 35 ) { lower_color[i][j] = 35; }
-	}
-	upper_color[i][3] = middle_color[i][3] = lower_color[i][3] = 
-	    (GLubyte)(l->sky_color[3] * 255);
-
-	for ( j = 0; j < 3; j++ ) {
-	    outer_amt[j] += outer_diff[j];
-	    middle_amt[j] += middle_diff[j];
-	}
-
-	/*
-	printf("upper_color[%d] = %.2f %.2f %.2f %.2f\n", i, upper_color[i][0],
-	       upper_color[i][1], upper_color[i][2], upper_color[i][3]);
-	printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i, 
-	       middle_color[i][0], middle_color[i][1], middle_color[i][2], 
-	       middle_color[i][3]);
-	printf("lower_color[%d] = %.2f %.2f %.2f %.2f\n", i, 
-	       lower_color[i][0], lower_color[i][1], lower_color[i][2], 
-	       lower_color[i][3]);
-	*/
-    }
-}
-
-
-// Initialize the sky structure and colors
-void fgSkyInit() {
-    FG_LOG( FG_ASTRO, FG_INFO, "Initializing the sky" );
-
-    fgSkyVerticesInit();
-
-    // regester fgSkyColorsInit() as an event to be run periodically
-    global_events.Register( "fgSkyColorsInit()", fgSkyColorsInit, 
-		            fgEVENT::FG_EVENT_READY, 30000);
-}
-
-
-// Draw the Sky
-void fgSkyRender() {
-    FGInterface *f;
-    fgLIGHT *l;
-    GLubyte sky_color[4];
-    GLubyte upper_color[4];
-    GLubyte middle_color[4];
-    GLubyte lower_color[4];
-    double diff;
-    int i;
-
-    f = current_aircraft.fdm_state;
-    l = &cur_light_params;
-
-    // printf("Rendering the sky.\n");
-
-    // calculate the proper colors
-    for ( i = 0; i < 3; i++ ) {
-	diff = l->sky_color[i] - l->adj_fog_color[i];
-
-	// printf("sky = %.2f  fog = %.2f  diff = %.2f\n", 
-	//        l->sky_color[j], l->adj_fog_color[j], diff);
-
-	upper_color[i] = (GLubyte)((l->sky_color[i] - diff * 0.3) * 255);
-	middle_color[i] = (GLubyte)((l->sky_color[i] - diff * 0.9) * 255);
-	lower_color[i] = (GLubyte)(l->adj_fog_color[i] * 255);
-    }
-    upper_color[3] = middle_color[3] = lower_color[3] = 
-	(GLubyte)(l->adj_fog_color[3] * 255);
-
-    xglPushMatrix();
-
-    // Translate to view position
-    Point3D zero_elev = current_view.get_cur_zero_elev();
-    xglTranslatef( zero_elev.x(), zero_elev.y(), zero_elev.z() );
-    // printf("  Translated to %.2f %.2f %.2f\n", 
-    //        zero_elev.x, zero_elev.y, zero_elev.z );
-
-    // Rotate to proper orientation
-    // printf("  lon = %.2f  lat = %.2f\n", FG_Longitude * RAD_TO_DEG,
-    //        FG_Latitude * RAD_TO_DEG);
-    xglRotatef( f->get_Longitude() * RAD_TO_DEG, 0.0, 0.0, 1.0 );
-    xglRotatef( 90.0 - f->get_Latitude() * RAD_TO_DEG, 0.0, 1.0, 0.0 );
-    xglRotatef( l->sun_rotation * RAD_TO_DEG, 0.0, 0.0, 1.0 );
-
-    // Draw inner/center section of sky*/
-    xglBegin( GL_TRIANGLE_FAN );
-    for ( i = 0; i < 4; i++ ) {
-	sky_color[i] = (GLubyte)(l->sky_color[i] * 255);
-    }
-    xglColor4fv(l->sky_color);
-    xglVertex3f(0.0, 0.0, CENTER_ELEV);
-    for ( i = 11; i >= 0; i-- ) {
-	xglColor4ubv( upper_color );
-	xglVertex3fv( inner_vertex[i] );
-    }
-    xglColor4ubv( upper_color );
-    xglVertex3fv( inner_vertex[11] );
-    xglEnd();
-
-    // Draw the middle ring
-    xglBegin( GL_TRIANGLE_STRIP );
-    for ( i = 0; i < 12; i++ ) {
-	xglColor4ubv( middle_color );
-	// printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i, 
-	//        middle_color[i][0], middle_color[i][1], middle_color[i][2], 
-	//        middle_color[i][3]);
-	// xglColor4f(1.0, 0.0, 0.0, 1.0);
-	xglVertex3fv( middle_vertex[i] );
-	xglColor4ubv( upper_color );
-	// printf("upper_color[%d] = %.2f %.2f %.2f %.2f\n", i, 
-	//        upper_color[i][0], upper_color[i][1], upper_color[i][2], 
-	//        upper_color[i][3]);
-	// xglColor4f(0.0, 0.0, 1.0, 1.0);
-	xglVertex3fv( inner_vertex[i] );
-    }
-    xglColor4ubv( middle_color );
-    // xglColor4f(1.0, 0.0, 0.0, 1.0);
-    xglVertex3fv( middle_vertex[0] );
-    xglColor4ubv( upper_color );
-    // xglColor4f(0.0, 0.0, 1.0, 1.0);
-    xglVertex3fv( inner_vertex[0] );
-    xglEnd();
-
-    // Draw the outer ring
-    xglBegin( GL_TRIANGLE_STRIP );
-    for ( i = 0; i < 12; i++ ) {
-	xglColor4ubv( lower_color );
-	xglVertex3fv( outer_vertex[i] );
-	xglColor4ubv( middle_color );
-	xglVertex3fv( middle_vertex[i] );
-    }
-    xglColor4ubv( lower_color );
-    xglVertex3fv( outer_vertex[0] );
-    xglColor4ubv( middle_color );
-    xglVertex3fv( middle_vertex[0] );
-    xglEnd();
-
-    // Draw the bottom skirt
-    xglBegin( GL_TRIANGLE_STRIP );
-    xglColor4ubv( lower_color );
-    for ( i = 0; i < 12; i++ ) {
-	xglVertex3fv( bottom_vertex[i] );
-	xglVertex3fv( outer_vertex[i] );
-    }
-    xglVertex3fv( bottom_vertex[0] );
-    xglVertex3fv( outer_vertex[0] );
-    xglEnd();
-
-    xglPopMatrix();
-}
-
-
-#endif
diff --git a/simgear/ephemeris/skydome.hxx b/simgear/ephemeris/skydome.hxx
deleted file mode 100644
index 7d9b159f..00000000
--- a/simgear/ephemeris/skydome.hxx
+++ /dev/null
@@ -1,109 +0,0 @@
-// skydome.hxx -- model sky with an upside down "bowl"
-//
-// Written by Curtis Olson, started December 1997.
-// SSG-ified by Curtis Olson, February 2000.
-//
-// Copyright (C) 1997-2000  Curtis L. Olson  - curt@flightgear.org
-//
-// This program is free software; you can redistribute it and/or
-// modify it under the terms of the GNU General Public License as
-// published by the Free Software Foundation; either version 2 of the
-// License, or (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful, but
-// WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-// General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program; if not, write to the Free Software
-// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-//
-// $Id$
-
-
-#ifndef _SKYDOME_HXX
-#define _SKYDOME_HXX
-
-
-#ifndef __cplusplus                                                          
-# error This library requires C++
-#endif                                   
-
-
-#include <plib/ssg.h>		// plib include
-
-
-class FGSkyDome {
-
-    ssgSelector *sky_selector;
-    ssgTransform *sky_transform;
-    ssgSimpleState *sky_state;
-
-    ssgVertexArray *center_disk_vl;
-    ssgColourArray *center_disk_cl;
-
-    ssgVertexArray *upper_ring_vl;
-    ssgColourArray *upper_ring_cl;
-
-    ssgVertexArray *middle_ring_vl;
-    ssgColourArray *middle_ring_cl;
-
-    ssgVertexArray *lower_ring_vl;
-    ssgColourArray *lower_ring_cl;
-
-public:
-
-    // Constructor
-    FGSkyDome( void );
-
-    // Destructor
-    ~FGSkyDome( void );
-
-    // initialize the sky object and connect it into the scene graph
-    // as a kid to to the specified root
-    bool initialize( ssgRoot *branch );
-
-    // repaint the sky colors based on current value of sun_angle,
-    // sky, and fog colors.  This updates the color arrays for
-    // ssgVtxTable.
-    // sun angle in degrees relative to verticle
-    // 0 degrees = high noon
-    // 90 degrees = sun rise/set
-    // 180 degrees = darkest midnight
-    bool repaint( sgVec3 sky_color, sgVec3 fog_color, double sun_angle );
-
-    // reposition the sky at the specified origin and orientation
-    // lon specifies a rotation about the Z axis
-    // lat specifies a rotation about the new Y axis
-    // spin specifies a rotation about the new Z axis (and orients the
-    // sunrise/set effects
-    bool reposition( sgVec3 p, double lon, double lat, double spin );
-
-    // enable the sky in the scene graph (default)
-    void enable() { sky_selector->select( 1 ); }
-
-    // disable the sky in the scene graph.  The leaf node is still
-    // there, how ever it won't be traversed on the cullandrender
-    // phase.
-    void disable() { sky_selector->select( 0 ); }
-
-};
-
-
-extern FGSkyDome current_sky;
-
-
-// (Re)generate the display list
-// void fgSkyInit();
-
-// (Re)calculate the sky colors at each vertex
-// void fgSkyColorsInit();
-
-// Draw the Sky
-// void fgSkyRender();
-
-
-#endif // _SKYDOM_HXX
-
-
diff --git a/simgear/ephemeris/solarsystem.cxx b/simgear/ephemeris/solarsystem.cxx
index c2bb1e74..75c5f007 100644
--- a/simgear/ephemeris/solarsystem.cxx
+++ b/simgear/ephemeris/solarsystem.cxx
@@ -141,7 +141,7 @@ void SolarSystem::rebuild()
 
     earthsMoon->newImage();
     // Step 2b:  Add the sun
-    ourSun->newImage();
+    // ourSun->newImage();
     // Step 2c: Add the planets
     xglBegin(GL_POINTS);
     mercury->getPos(&ra, &dec, &magnitude);addPlanetToList(ra, dec, magnitude);
diff --git a/simgear/ephemeris/star.cxx b/simgear/ephemeris/star.cxx
index 01f8c0d6..c036521a 100644
--- a/simgear/ephemeris/star.cxx
+++ b/simgear/ephemeris/star.cxx
@@ -45,56 +45,38 @@
  * problems on sun systems 
  ************************************************************************/
 Star::Star(FGTime *t) :
-  CelestialBody (0.000000,  0.0000000000,
-		 0.0000,    0.00000,
-		 282.9404,  4.7093500E-5,	
-		 1.0000000, 0.000000,	
-		 0.016709,  -1.151E-9,
-		 356.0470,  0.98560025850, t)
+    CelestialBody (0.000000,  0.0000000000,
+		   0.0000,    0.00000,
+		   282.9404,  4.7093500E-5,	
+		   1.0000000, 0.000000,	
+		   0.016709,  -1.151E-9,
+		   356.0470,  0.98560025850, t)
 {
-    
-  FG_LOG( FG_GENERAL, FG_INFO, "Initializing Sun Texture");
-#ifdef GL_VERSION_1_1
-  xglGenTextures(1, &sun_texid);
-  xglBindTexture(GL_TEXTURE_2D, sun_texid);
-#elif GL_EXT_texture_object
-  xglGenTexturesEXT(1, &sun_texid);
-  xglBindTextureEXT(GL_TEXTURE_2D, sun_texid);
-#else
-#  error port me
-#endif
+    distance = 0.0;
+}
 
-  glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
-  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
-  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-  setTexture();
-  glTexImage2D( GL_TEXTURE_2D,
-		0,
-		GL_RGBA,
-		256, 256,
-		0,
-		GL_RGBA, GL_UNSIGNED_BYTE,
-		sun_texbuf);
-     
-  SunObject = gluNewQuadric();
-  if(SunObject == NULL)
-    {
-      printf("gluNewQuadric(SunObject) failed  !\n");
-      exit(0);
-    }
-  
-  //SunList = 0;
-  distance = 0.0;
+Star::Star() :
+    CelestialBody (0.000000,  0.0000000000,
+		   0.0000,    0.00000,
+		   282.9404,  4.7093500E-5,	
+		   1.0000000, 0.000000,	
+		   0.016709,  -1.151E-9,
+		   356.0470,  0.98560025850)
+{
+    distance = 0.0;
 }
 
 Star::~Star()
 {
+#if 0
   //delete SunObject;
   delete [] sun_texbuf;
+#endif
 }
 
 
 
+#if 0
 static int texWidth = 256;	/* 64x64 is plenty */
 
 void Star::setTexture()
@@ -142,6 +124,9 @@ void Star::setTexture()
   //	    GL_UNSIGNED_BYTE, textureBuf);
   //free(textureBuf);
 }
+#endif
+
+
 /*************************************************************************
  * void Jupiter::updatePosition(FGTime *t, Star *ourSun)
  * 
@@ -184,7 +169,9 @@ void Star::updatePosition(FGTime *t)
   rightAscension = atan2 (ye, xe);
   declination = atan2 (ze, sqrt (xe*xe + ye*ye));
 }
-  
+
+
+#if 0  
 void Star::newImage(void)
 {
   /*static float stars[3];
@@ -268,3 +255,4 @@ void Star::newImage(void)
     glDisable(GL_BLEND);	// BLEND DISABLED  
   }
 }
+#endif
diff --git a/simgear/ephemeris/star.hxx b/simgear/ephemeris/star.hxx
index 6eb7a4c9..1a46c650 100644
--- a/simgear/ephemeris/star.hxx
+++ b/simgear/ephemeris/star.hxx
@@ -30,29 +30,30 @@
 
 class Star : public CelestialBody
 {
+
 private:
-  //double longitude;  // the sun's true longitude - this is depreciated by
-                       // CelestialBody::lonEcl 
-  double xs, ys;     // the sun's rectangular geocentric coordinates
-  double distance;   // the sun's distance to the earth
-   GLUquadricObj *SunObject;
-  GLuint sun_texid;
-  GLubyte *sun_texbuf;
-
-  void setTexture();
+
+    double xs, ys;     // the sun's rectangular geocentric coordinates
+    double distance;   // the sun's distance to the earth
+    // GLUquadricObj *SunObject;
+    // GLuint sun_texid;
+    // GLubyte *sun_texbuf;
+    // void setTexture();
+
 public:
-  Star (FGTime *t);
-  ~Star();
-  void updatePosition(FGTime *t);
-  double getM();
-  double getw();
-  //double getLon();
-  double getxs();
-  double getys();
-  double getDistance();
-  void newImage();
-};
 
+    Star (FGTime *t);
+    Star ();
+    ~Star();
+    void updatePosition(FGTime *t);
+    double getM();
+    double getw();
+    //double getLon();
+    double getxs();
+    double getys();
+    double getDistance();
+    // void newImage();
+};
 
 
 inline double Star::getM()
diff --git a/simgear/sky/skydome.cxx b/simgear/sky/skydome.cxx
index a5aa97f4..48d62bfe 100644
--- a/simgear/sky/skydome.cxx
+++ b/simgear/sky/skydome.cxx
@@ -79,10 +79,6 @@
 // static GLubyte lower_color[12][4];
 
 
-// Defined the shared sky object here
-FGSkyDome current_sky;
-
-
 // Constructor
 FGSkyDome::FGSkyDome( void ) {
 }
diff --git a/simgear/sky/skydome.hxx b/simgear/sky/skydome.hxx
index 1ec80441..7cb7249d 100644
--- a/simgear/sky/skydome.hxx
+++ b/simgear/sky/skydome.hxx
@@ -96,9 +96,6 @@ public:
 };
 
 
-extern FGSkyDome current_sky;
-
-
 // (Re)generate the display list
 // void fgSkyInit();
 
diff --git a/simgear/sky/skysun.cxx b/simgear/sky/skysun.cxx
index 583593f7..2fd98352 100644
--- a/simgear/sky/skysun.cxx
+++ b/simgear/sky/skysun.cxx
@@ -24,18 +24,11 @@
 // $Id$
 
 
-// #ifdef __BORLANDC__
-// #  define exception c_exception
-// #endif
-// #include <math.h>
-
-// #include <simgear/debug/logstream.hxx>
-
-// #include <Time/sunpos.hxx>
-// #include <Time/light.hxx>
-// #include <Main/options.hxx>
+#include <plib/ssg.h>
 
+#include <simgear/constants.h>
 
+#include "sphere.hxx"
 #include "skysun.hxx"
 
 
@@ -51,151 +44,115 @@ FGSkySun::~FGSkySun( void ) {
 
 // initialize the sun object and connect it into our scene graph root
 bool FGSkySun::initialize() {
-    sgVec3 color;
-
-    float theta;
-    int i;
 
     // create the scene graph for the dome
     skysun = new ssgRoot;
     skysun->setName( "Sky Sun" );
 
     // set up the state
-    sun_state = new ssgSimpleState();
-    sun_state->setShadeModel( GL_SMOOTH );
-    sun_state->disable( GL_LIGHTING );
-    sun_state->disable( GL_DEPTH_TEST );
-    sun_state->disable( GL_CULL_FACE );
-    sun_state->disable( GL_TEXTURE_2D );
-    sun_state->disable( GL_COLOR_MATERIAL );
-    sun_state->setColourMaterial( GL_AMBIENT_AND_DIFFUSE );
-
-    // initially seed to all white
-    sgSetVec3( color, 1.0, 1.0, 1.0 );
-
-    // generate the raw vertex data
-    sgVec3 center_vertex;
-    sgVec3 upper_vertex[12];
-    sgVec3 middle_vertex[12];
-    sgVec3 lower_vertex[12];
-    sgVec3 bottom_vertex[12];
-
-    sgSetVec3( center_vertex, 0.0, 0.0, CENTER_ELEV );
-
-    for ( i = 0; i < 12; i++ ) {
-	theta = (i * 30.0) * DEG_TO_RAD;
-
-	sgSetVec3( upper_vertex[i],
-		   cos(theta) * UPPER_RADIUS,
-		   sin(theta) * UPPER_RADIUS,
-		   UPPER_ELEV );
-	
-	sgSetVec3( middle_vertex[i],
-		   cos((double)theta) * MIDDLE_RADIUS,
-		   sin((double)theta) * MIDDLE_RADIUS,
-		   MIDDLE_ELEV );
-
-	sgSetVec3( lower_vertex[i],
-		   cos((double)theta) * LOWER_RADIUS,
-		   sin((double)theta) * LOWER_RADIUS,
-		   LOWER_ELEV );
-
-	sgSetVec3( bottom_vertex[i],
-		   cos((double)theta) * BOTTOM_RADIUS,
-		   sin((double)theta) * BOTTOM_RADIUS,
-		   BOTTOM_ELEV );
-    }
+    orb_state = new ssgSimpleState();
+    orb_state->setShadeModel( GL_SMOOTH );
+    orb_state->disable( GL_LIGHTING );
+    orb_state->disable( GL_DEPTH_TEST );
+    orb_state->disable( GL_CULL_FACE );
+    orb_state->disable( GL_TEXTURE_2D );
+    orb_state->disable( GL_COLOR_MATERIAL );
+    orb_state->setMaterial( GL_AMBIENT_AND_DIFFUSE, 1.0, 1.0, 1.0, 1.0 );
 
-    // generate the center disk vertex/color arrays
-    center_disk_vl->add( center_vertex );
-    center_disk_cl->add( color );
-    for ( i = 11; i >= 0; i-- ) {
-	center_disk_vl->add( upper_vertex[i] );
-	center_disk_cl->add( color );
-    }
-    center_disk_vl->add( upper_vertex[11] );
-    center_disk_cl->add( color );
+    ssgBranch *orb = ssgMakeSphere( orb_state, 550.0, 10, 10 );
 
-    // generate the upper ring
-    for ( i = 0; i < 12; i++ ) {
-	upper_ring_vl->add( middle_vertex[i] );
-	upper_ring_cl->add( color );
+    // force a repaint of the sun colors with arbitrary defaults
+    repaint( 0.0 );
 
-	upper_ring_vl->add( upper_vertex[i] );
-	upper_ring_cl->add( color );
-    }
-    upper_ring_vl->add( middle_vertex[0] );
-    upper_ring_cl->add( color );
+    // build the ssg scene graph sub tree for the sky and connected
+    // into the provide scene graph branch
+    sun_selector = new ssgSelector;
+    sun_transform = new ssgTransform;
 
-    upper_ring_vl->add( upper_vertex[0] );
-    upper_ring_cl->add( color );
+    // orb->setState( orb_state );
 
-    // generate middle ring
-    for ( i = 0; i < 12; i++ ) {
-	middle_ring_vl->add( lower_vertex[i] );
-	middle_ring_cl->add( color );
+    sun_transform->addKid( orb );
 
-	middle_ring_vl->add( middle_vertex[i] );
-	middle_ring_cl->add( color );
-    }
-    middle_ring_vl->add( lower_vertex[0] );
-    middle_ring_cl->add( color );
+    sun_selector->addKid( sun_transform );
+    sun_selector->clrTraversalMaskBits( SSGTRAV_HOT );
 
-    middle_ring_vl->add( middle_vertex[0] );
-    middle_ring_cl->add( color );
+    skysun->addKid( sun_selector );
 
-    // generate lower ring
-    for ( i = 0; i < 12; i++ ) {
-	lower_ring_vl->add( bottom_vertex[i] );
-	lower_ring_cl->add( color );
+    return true;
+}
 
-	lower_ring_vl->add( lower_vertex[i] );
-	lower_ring_cl->add( color );
+
+// repaint the sun colors based on current value of sun_angle in
+// degrees relative to verticle
+// 0 degrees = high noon
+// 90 degrees = sun rise/set
+// 180 degrees = darkest midnight
+bool FGSkySun::repaint( double sun_angle ) {
+    if ( sun_angle * RAD_TO_DEG < 100 ) {
+	// else sun is well below horizon (so no point in repainting it)
+    
+	// x_10 = sun_angle^10
+	double x_10 = sun_angle * sun_angle * sun_angle * sun_angle * sun_angle
+	    * sun_angle * sun_angle * sun_angle * sun_angle * sun_angle;
+
+	float ambient = (float)(0.4 * pow (1.1, - x_10 / 30.0));
+	if (ambient < 0.3) { ambient = 0.3; }
+	if (ambient > 1.0) { ambient = 1.0; }
+
+	sgVec3 color;
+	sgSetVec3( color,
+		   (ambient * 6.0)  - 1.0, // minimum value = 0.8
+		   (ambient * 11.0) - 3.0, // minimum value = 0.3
+		   (ambient * 12.0) - 3.6  // minimum value = 0.0
+		   );
+    
+	if (color[0] > 1.0) color[0] = 1.0;
+	if (color[1] > 1.0) color[1] = 1.0;
+	if (color[2] > 1.0) color[2] = 1.0;
+
+	orb_state->setMaterial( GL_AMBIENT_AND_DIFFUSE, 
+				color[0], color[1], color[2], 1.0 );
     }
-    lower_ring_vl->add( bottom_vertex[0] );
-    lower_ring_cl->add( color );
 
-    lower_ring_vl->add( lower_vertex[0] );
-    lower_ring_cl->add( color );
+    return true;
+}
 
-    // force a repaint of the sky colors with ugly defaults
-    sgVec3 fog_color;
-    sgSetVec3( fog_color, 1.0, 1.0, 1.0 );
-    repaint( color, fog_color, 0.0 );
 
-    // build the ssg scene graph sub tree for the sky and connected
-    // into the provide scene graph branch
-    dome_selector = new ssgSelector;
-    dome_transform = new ssgTransform;
+// reposition the sun at the specified right ascension and declination
+bool FGSkySun::reposition( double rightAscension, double declination ) {
+    sgMat4 T, RA, DEC;
+    sgVec3 axis;
+    sgVec3 v;
 
-    ssgVtxTable *center_disk, *upper_ring, *middle_ring, *lower_ring;
+    // xglRotatef(((RAD_TO_DEG * rightAscension)- 90.0), 0.0, 0.0, 1.0);
+    sgSetVec3( axis, 0.0, 0.0, 1.0 );
+    sgMakeRotMat4( RA, (rightAscension * RAD_TO_DEG) - 90.0, axis );
 
-    center_disk = new ssgVtxTable( GL_TRIANGLE_FAN, 
-				   center_disk_vl, NULL, NULL, center_disk_cl );
+    // xglRotatef((RAD_TO_DEG * declination), 1.0, 0.0, 0.0);
+    sgSetVec3( axis, 1.0, 0.0, 0.0 );
+    sgMakeRotMat4( DEC, declination * RAD_TO_DEG, axis );
 
-    upper_ring = new ssgVtxTable( GL_TRIANGLE_STRIP, 
-				  upper_ring_vl, NULL, NULL, upper_ring_cl );
+    // xglTranslatef(0,60000,0);
+    sgSetVec3( v, 0.0, 60000.0, 0.0 );
+    sgMakeTransMat4( T, v );
 
-    middle_ring = new ssgVtxTable( GL_TRIANGLE_STRIP, 
-				   middle_ring_vl, NULL, NULL, middle_ring_cl );
+    sgMat4 TRANSFORM;
+    sgCopyMat4( TRANSFORM, RA );
+    sgPreMultMat4( TRANSFORM, DEC );
+    sgPreMultMat4( TRANSFORM, T );
 
-    lower_ring = new ssgVtxTable( GL_TRIANGLE_STRIP, 
-				  lower_ring_vl, NULL, NULL, lower_ring_cl );
+    sgCoord skypos;
+    sgSetCoord( &skypos, TRANSFORM );
 
-    center_disk->setState( dome_state );
-    upper_ring->setState( dome_state );
-    middle_ring->setState( dome_state );
-    lower_ring->setState( dome_state );
+    sun_transform->setTransform( &skypos );
 
-    dome_transform->addKid( center_disk );
-    dome_transform->addKid( upper_ring );
-    dome_transform->addKid( middle_ring );
-    dome_transform->addKid( lower_ring );
+    return true;
+}
 
-    dome_selector->addKid( dome_transform );
-    dome_selector->clrTraversalMaskBits( SSGTRAV_HOT );
 
-    dome->addKid( dome_selector );
+// Draw the sun
+bool FGSkySun::draw() {
+    ssgCullAndDraw( skysun );
 
     return true;
 }
diff --git a/simgear/sky/skysun.hxx b/simgear/sky/skysun.hxx
index 16d29472..59fa1c50 100644
--- a/simgear/sky/skysun.hxx
+++ b/simgear/sky/skysun.hxx
@@ -38,7 +38,7 @@ class FGSkySun {
 
     ssgSelector *sun_selector;
     ssgTransform *sun_transform;
-    ssgSimpleState *sun_state;
+    ssgSimpleState *orb_state;
     ssgSimpleState *halo_state;
 
 public:
@@ -58,7 +58,7 @@ public:
     // 0 degrees = high noon
     // 90 degrees = sun rise/set
     // 180 degrees = darkest midnight
-    bool repaint( sgVec3 sky_color, sgVec3 fog_color, double sun_angle );
+    bool repaint( double sun_angle );
 
     // reposition the sun at the specified right ascension and
     // declination
diff --git a/simgear/sky/sphere.cxx b/simgear/sky/sphere.cxx
index 285c38f0..c7eabd0f 100644
--- a/simgear/sky/sphere.cxx
+++ b/simgear/sky/sphere.cxx
@@ -26,7 +26,8 @@
 
 
 // return a sphere object as an ssgBranch
-ssgBranch *ssgMakeSphere( double radius, int slices, int stacks ) {
+ssgBranch *ssgMakeSphere( ssgSimpleState *state, double radius, int slices,
+			  int stacks ) {
     float rho, drho, theta, dtheta;
     float x, y, z;
     float s, t, ds, dt;
@@ -96,6 +97,7 @@ ssgBranch *ssgMakeSphere( double radius, int slices, int stacks ) {
 
 	ssgLeaf *slice = 
 	    new ssgVtxTable ( GL_TRIANGLE_STRIP, vl, nl, tl, NULL );
+	slice->setState( state );
 
 	sphere->addKid( slice );
 
diff --git a/simgear/sky/sphere.hxx b/simgear/sky/sphere.hxx
index a5a66a8a..5d64b101 100644
--- a/simgear/sky/sphere.hxx
+++ b/simgear/sky/sphere.hxx
@@ -25,5 +25,9 @@
 #include <plib/ssg.h>
 
 
-// return a sphere object as an ssgBranch
-ssgBranch *ssgMakeSphere( double radius, int slices, int stacks );
+// return a sphere object as an ssgBranch (and connect in the
+// specified ssgSimpleState
+ssgBranch *ssgMakeSphere( ssgSimpleState *state, double radius, int slices,
+			  int stacks );
+
+