//
// Written by Curtis Olson, started July 2000.
//
-// Copyright (C) 2000 Curtis L. Olson - curt@flightgear.org
+// Copyright (C) 2000 Curtis L. Olson - http://www.flightgear.org/~curt
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
//
// 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.
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
//
// $Id$
# include <config.h>
#endif
+#include <simgear/math/SGMath.hxx>
+#include <simgear/math/vector.hxx>
#include <simgear/misc/sg_path.hxx>
-#include <simgear/magvar/magvar.hxx>
#include <simgear/timing/sg_time.hxx>
-#include <FDM/flight.hxx>
#include <Main/fg_props.hxx>
#include <Main/globals.hxx>
+#include <Main/viewer.hxx>
+#include <Scenery/scenery.hxx>
#include "light.hxx"
-#include "moonpos.hxx"
-#include "sunpos.hxx"
+#include "sunsolver.hxx"
#include "tmp.hxx"
zone.str() );
}
+
+// update the cur_time_params structure with the current sun position
+void fgUpdateSunPos( void ) {
+ FGLight *l = (FGLight *)(globals->get_subsystem("lighting"));
+ SGTime *t = globals->get_time_params();
+ FGViewer *v = globals->get_current_view();
+
+ SG_LOG( SG_EVENT, SG_DEBUG, " Updating Sun position" );
+ SG_LOG( SG_EVENT, SG_DEBUG, " Gst = " << t->getGst() );
+
+ double sun_l;
+ double sun_gd_lat;
+ fgSunPositionGST(t->getGst(), &sun_l, &sun_gd_lat);
+ l->set_sun_lon(sun_l);
+ l->set_sun_lat(sun_gd_lat);
+ l->set_sunpos(SGVec3d::fromGeod(SGGeod::fromRad(sun_l, sun_gd_lat)));
+
+ SG_LOG( SG_EVENT, SG_DEBUG, " t->cur_time = " << t->get_cur_time() );
+ SG_LOG( SG_EVENT, SG_DEBUG,
+ " Sun Geodetic lat = " << sun_gd_lat
+ << " Geodetic lat = " << sun_gd_lat );
+
+ // update the sun light vector
+ l->sun_vec() = SGVec4f(toVec3f(normalize(l->get_sunpos())), 0);
+ l->sun_vec_inv() = - l->sun_vec();
+
+ // calculate the sun's relative angle to local up
+ SGVec3d viewPos = v->get_view_pos();
+ SGQuatd hlOr = SGQuatd::fromLonLat(SGGeod::fromCart(viewPos));
+ SGVec3f nup(toVec3f(hlOr.backTransform(-SGVec3d::e3())));
+
+ SGVec3f nsun(toVec3f(normalize(l->get_sunpos())));
+ // cout << "nup = " << nup[0] << "," << nup[1] << ","
+ // << nup[2] << endl;
+ // cout << "nsun = " << nsun[0] << "," << nsun[1] << ","
+ // << nsun[2] << endl;
+
+ l->set_sun_angle( acos( dot ( nup, nsun ) ) );
+ SG_LOG( SG_EVENT, SG_DEBUG, "sun angle relative to current location = "
+ << l->get_sun_angle() );
+
+ // calculate vector to sun's position on the earth's surface
+ SGVec3d rel_sunpos = l->get_sunpos() - v->get_view_pos();
+ // vector in cartesian coordinates from current position to the
+ // postion on the earth's surface the sun is directly over
+ SGVec3f to_sun = toVec3f(rel_sunpos);
+ // printf( "Vector to sun = %.2f %.2f %.2f\n",
+ // v->to_sun[0], v->to_sun[1], v->to_sun[2]);
+
+ // Given a vector from the view position to the point on the
+ // earth's surface the sun is directly over, map into onto the
+ // local plane representing "horizontal".
+
+ SGVec3f world_up = toVec3f(hlOr.backTransform(-SGVec3d::e3()));
+ SGVec3f view_pos = toVec3f(v->get_view_pos());
+ // surface direction to go to head towards sun
+ SGVec3f surface_to_sun;
+ sgmap_vec_onto_cur_surface_plane( world_up.data(), view_pos.data(),
+ to_sun.data(), surface_to_sun.data() );
+ surface_to_sun = normalize(surface_to_sun);
+ // cout << "(sg) Surface direction to sun is "
+ // << surface_to_sun[0] << ","
+ // << surface_to_sun[1] << ","
+ // << surface_to_sun[2] << endl;
+ // cout << "Should be close to zero = "
+ // << sgScalarProductVec3(nup, surface_to_sun) << endl;
+
+ // calculate the angle between surface_to_sun and
+ // v->get_surface_east(). We do this so we can sort out the
+ // acos() ambiguity. I wish I could think of a more efficient
+ // way. :-(
+ SGVec3f surface_east(toVec3f(hlOr.backTransform(SGVec3d::e2())));
+ float east_dot = dot( surface_to_sun, surface_east );
+ // cout << " East dot product = " << east_dot << endl;
+
+ // calculate the angle between v->surface_to_sun and
+ // v->surface_south. this is how much we have to rotate the sky
+ // for it to align with the sun
+ SGVec3f surface_south(toVec3f(hlOr.backTransform(-SGVec3d::e1())));
+ float dot_ = dot( surface_to_sun, surface_south );
+ // cout << " Dot product = " << dot << endl;
+
+ if (dot_ > 1.0) {
+ SG_LOG( SG_ASTRO, SG_INFO,
+ "Dot product = " << dot_ << " is greater than 1.0" );
+ dot_ = 1.0;
+ }
+ else if (dot_ < -1.0) {
+ SG_LOG( SG_ASTRO, SG_INFO,
+ "Dot product = " << dot_ << " is less than -1.0" );
+ dot_ = -1.0;
+ }
+
+ if ( east_dot >= 0 ) {
+ l->set_sun_rotation( acos(dot_) );
+ } else {
+ l->set_sun_rotation( -acos(dot_) );
+ }
+ // cout << " Sky needs to rotate = " << angle << " rads = "
+ // << angle * SGD_RADIANS_TO_DEGREES << " degrees." << endl;
+}
+