void SkyPoint::findEcliptic( const dms *Obliquity, dms &EcLong, dms &EcLat ) {
double sinRA, cosRA, sinOb, cosOb, sinDec, cosDec, tanDec;
ra().SinCos( sinRA, cosRA );
dec().SinCos( sinDec, cosDec );
Obliquity->SinCos( sinOb, cosOb );
tanDec = sinDec/cosDec; // FIXME: -jbb div by zero?
double y = sinRA*cosOb + tanDec*sinOb;
double ELongRad = atan2( y, cosRA );
EcLong.setRadians( ELongRad );
EcLong.reduce();
EcLat.setRadians( asin( sinDec*cosOb - cosDec*sinOb*sinRA ) );
}
void SkyPoint::setFromEcliptic( const dms *Obliquity, const dms& EcLong, const dms& EcLat ) {
double sinLong, cosLong, sinLat, cosLat, sinObliq, cosObliq;
EcLong.SinCos( sinLong, cosLong );
EcLat.SinCos( sinLat, cosLat );
Obliquity->SinCos( sinObliq, cosObliq );
double sinDec = sinLat*cosObliq + cosLat*sinObliq*sinLong;
double y = sinLong*cosObliq - (sinLat/cosLat)*sinObliq;
double RARad = atan2( y, cosLong );
RA.setRadians( RARad );
RA.reduce();
Dec.setRadians( asin(sinDec) );
}
QString KSUtils::toDirectionString( dms angle ) {
// TODO: Instead of doing it this way, it would be nicer to
// compute the string to arbitrary precision. Although that will
// not be easy to localize. (Consider, for instance, Indian
// languages that have special names for the intercardinal points)
// -- asimha
static const char *directions[] = {
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "N"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "NNE"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "NE"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "ENE"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "E"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "ESE"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "SE"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "SSE"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "S"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "SSW"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "SW"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "WSW"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "W"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "WNW"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "NW"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "NNW"),
I18N_NOOP2( "Abbreviated cardinal / intercardinal etc. direction", "N"),
};
int index = (int)( (angle.Degrees() + 11.25) / 22.5); // A number between 0 and 16 (inclusive), 16 meaning the same thing as zero.
return i18nc( "Abbreviated cardinal / intercardinal etc. direction", directions[ index ] );
}
void SkyPoint::Equatorial1950ToGalactic(dms &galLong, dms &galLat) {
double a = 192.25;
double sinb, cosb, sina_RA, cosa_RA, sinDEC, cosDEC, tanDEC;
dms c(303.0);
dms b(27.4);
tanDEC = tan( Dec.radians() );
b.SinCos(sinb,cosb);
dms( a - RA.Degrees() ).SinCos(sina_RA,cosa_RA);
Dec.SinCos(sinDEC,cosDEC);
galLong.setRadians( c.radians() - atan2( sina_RA, cosa_RA*sinb-tanDEC*cosb) );
galLong = galLong.reduce();
galLat.setRadians( asin(sinDEC*sinb+cosDEC*cosb*cosa_RA) );
}
bool SkyPoint::checkBendLight() {
// First see if we are close enough to the sun to bother about the
// gravitational lensing effect. We correct for the effect at
// least till b = 10 solar radii, where the effect is only about
// 0.06". Assuming min. sun-earth distance is 200 solar radii.
static const dms maxAngle( 1.75 * ( 30.0 / 200.0) / dms::DegToRad );
if( !m_Sun )
m_Sun = (KSSun*) KStarsData::Instance()->skyComposite()->findByName( "Sun" );
// TODO: This can be optimized further. We only need a ballpark estimate of the distance to the sun to start with.
return ( fabs( angularDistanceTo( static_cast<const SkyPoint *>(m_Sun) ).Degrees() ) <= maxAngle.Degrees() ); // NOTE: dynamic_cast is slow and not important here.
}
QTime KStarsDateTime::GSTtoUT( dms GST ) const {
dms gst0 = GSTat0hUT();
//dt is the number of sidereal hours since UT 0h.
double dt = GST.Hours() - gst0.Hours();
while ( dt < 0.0 ) dt += 24.0;
while ( dt >= 24.0 ) dt -= 24.0;
//convert to solar time. dt is now the number of hours since 0h UT.
dt /= SIDEREALSECOND;
int hr = int( dt );
int mn = int( 60.0*( dt - double( hr ) ) );
int sc = int( 60.0*( 60.0*( dt - double( hr ) ) - double( mn ) ) );
int ms = int( 1000.0*( 60.0*( 60.0*( dt - double(hr) ) - double(mn) ) - double(sc) ) );
return( QTime( hr, mn, sc, ms ) );
}
QString KSUtils::getDSSURL( const dms &ra, const dms &dec, float width, float height, const QString & type) {
const QString URLprefix( "http://archive.stsci.edu/cgi-bin/dss_search?v=poss2ukstu_blue" );
QString URLsuffix = QString( "&e=J2000&f=%1&c=none&fov=NONE" ).arg(type);
const double dss_default_size = Options::defaultDSSImageSize();
char decsgn = ( dec.Degrees() < 0.0 ) ? '-' : '+';
int dd = abs( dec.degree() );
int dm = abs( dec.arcmin() );
int ds = abs( dec.arcsec() );
// Infinite and NaN sizes are replaced by the default size
if( !qIsFinite( height ) )
height = dss_default_size;
if( !qIsFinite( width ) )
width = dss_default_size;
// Negative / zero sizes are replaced by the default size
if( height <= 0.0 )
height = dss_default_size;
if( width <= 0.0 )
width = dss_default_size;
// DSS accepts images that are no larger than 75 arcminutes
if( height > 75.0 )
height = 75.0;
if( width > 75.0 )
width = 75.0;
QString RAString, DecString, SizeString;
DecString = DecString.sprintf( "&d=%c%02d+%02d+%02d", decsgn, dd, dm, ds );
RAString = RAString.sprintf( "&r=%02d+%02d+%02d", ra.hour(), ra.minute(), ra.second() );
SizeString = SizeString.sprintf( "&h=%02.1f&w=%02.1f", height, width );
return ( URLprefix + RAString + DecString + SizeString + URLsuffix );
}
void dmsBox::showInHours (dms d)
{
double seconds = d.second() + d.msecond()/1000.;
setDMS( QString().sprintf( "%02d %02d %05.2f", d.hour(), d.minute(), seconds ) );
}
void dmsBox::showInDegrees (dms d)
{
double seconds = d.arcsec() + d.marcsec()/1000.;
setDMS( QString().sprintf( "%02d %02d %05.2f", d.degree(), d.arcmin(), seconds ) );
}
/// Can be constructed with an EAST dms-class
inline explicit longitude(const dms<east, T>& v)
: detail::graticule<T>(v.as_value())
{}
/// Can be constructed with a SOUTH dms-class
inline explicit latitude(const dms<south,T>& v)
: detail::graticule<T>(v.as_value())
{}
/// Can be constructed with a WEST dms-class
inline explicit longitude(dms<west, T> const& v)
: detail::graticule<T>(v.as_value())
{}
/// Can be constructed with a NORTH dms-class
inline explicit latitude(dms<north,T> const& v)
: detail::graticule<T>(v.as_value())
{}
