Method getSunDirection

src/Geoscape/Globe.cpp:1126–1173

* Get position of sun from point on globe * @param lon longitude of position * @param lat latitude of position * @return position of sun */

 * @return position of sun
 */
Cord Globe::getSunDirection(double lon, double lat) const
{
	const double curTime = _game->getSavedGame()->getTime()->getDaylight();
	const double rot = curTime * 2*M_PI;
	double sun;

	if (Options::globeSeasons)
	{
		const int MonthDays1[] = {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365};
		const int MonthDays2[] = {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366};

		int year=_game->getSavedGame()->getTime()->getYear();
		int month=_game->getSavedGame()->getTime()->getMonth()-1;
		int day=_game->getSavedGame()->getTime()->getDay()-1;

		double tm = (double)(( _game->getSavedGame()->getTime()->getHour() * 60
			+ _game->getSavedGame()->getTime()->getMinute() ) * 60
			+ _game->getSavedGame()->getTime()->getSecond() ) / 86400; //day fraction is also taken into account

		double CurDay;
		if (year%4 == 0 && !(year%100 == 0 && year%400 != 0))
			CurDay = (MonthDays2[month] + day + tm )/366 - 0.219; //spring equinox (start of astronomic year)
		else
			CurDay = (MonthDays1[month] + day + tm )/365 - 0.219;
		if (CurDay<0) CurDay += 1.;

		sun = -0.261 * sin(CurDay*2*M_PI);
	}
	else
		sun = 0;

	Cord sun_direction(cos(rot+lon), sin(rot+lon)*-sin(lat), sin(rot+lon)*cos(lat));

	Cord pole(0, cos(lat), sin(lat));

	if (sun>0)
		 sun_direction *= 1. - sun;
	else
		 sun_direction *= 1. + sun;

	pole *= sun;
	sun_direction += pole;
	double norm = sun_direction.norm();
	//norm should be always greater than 0
	norm = 1./norm;
	sun_direction *= norm;
	return sun_direction;
}


void Globe::drawShadow()