C++ (Cpp) SkyPoint::ra0 Examples

Example #1

dms SkyObject::riseSetTimeAz( const KStarsDateTime &dt, const GeoLocation *geo, bool riseT ) {
	dms Azimuth;
	double AltRad, AzRad;
	double sindec, cosdec, sinlat, coslat, sinHA, cosHA;
	double sinAlt, cosAlt;

	QTime UT = riseSetTimeUT( dt, geo, riseT );
	KStarsDateTime dt0 = dt;
	dt0.setTime( UT );
	SkyPoint sp = recomputeCoords( dt0, geo );
	const dms *ram = sp.ra0();
	const dms *decm = sp.dec0();

	dms LST = auxRiseSetTimeLST( geo->lat(), ram, decm, riseT );
	dms HourAngle = dms( LST.Degrees() - ram->Degrees() );

	geo->lat()->SinCos( sinlat, coslat );
	dec()->SinCos( sindec, cosdec );
	HourAngle.SinCos( sinHA, cosHA );

	sinAlt = sindec*sinlat + cosdec*coslat*cosHA;
	AltRad = asin( sinAlt );
	cosAlt = cos( AltRad );

	AzRad = acos( ( sindec - sinlat*sinAlt )/( coslat*cosAlt ) );
	if ( sinHA > 0.0 ) AzRad = 2.0*dms::PI - AzRad; // resolve acos() ambiguity
	Azimuth.setRadians( AzRad );

	return Azimuth;
}

Example #2

File: deepstarcomponent.cpp Project: KDE/kstars

bool DeepStarComponent::starsInAperture( QList<StarObject *> &list, const SkyPoint &center, float radius, float maglim )
{

    if( maglim < triggerMag )
        return false;

    // For DeepStarComponents, whether we use ra0() and dec0(), or
    // ra() and dec(), should not matter, because the stars are
    // repeated in all trixels that they will pass through, although
    // the factuality of this statement needs to be verified

    // Ensure that we have deprecessed the (RA, Dec) to (RA0, Dec0)
    Q_ASSERT( center.ra0().Degrees() >= 0.0 );
    Q_ASSERT( center.dec0().Degrees() <= 90.0 );

    m_skyMesh->intersect( center.ra0().Degrees(), center.dec0().Degrees(), radius, (BufNum) OBJ_NEAREST_BUF );

    MeshIterator region( m_skyMesh, OBJ_NEAREST_BUF );

    if( maglim < -28 )
        maglim = m_FaintMagnitude;

    while ( region.hasNext() ) {
        Trixel currentRegion = region.next();
        // FIXME: Build a better way to iterate over all stars.
        // Ideally, StarBlockList should have such a facility.
        StarBlockList *sbl = m_starBlockList[ currentRegion ];
        sbl->fillToMag( maglim );
        for( int i = 0; i < sbl->getBlockCount(); ++i ) {
            StarBlock *block = sbl->block( i );
            for( int j = 0; j < block->getStarCount(); ++j ) {
#ifdef KSTARS_LITE
                StarObject *star = &(block->star( j )->star);
#else
                StarObject *star = block->star( j );
#endif
                if( star->mag() > maglim )
                    break; // Stars are organized by magnitude, so this should work
                if( star->angularDistanceTo( &center ).Degrees() <= radius )
                    list.append( star );
            }
        }
    }

    return true;
}

Example #3

QTime SkyObject::transitTimeUT( const KStarsDateTime &dt, const GeoLocation *geo ) {
	dms LST = geo->GSTtoLST( dt.gst() );

	//dSec is the number of seconds until the object transits.
	dms HourAngle = dms( LST.Degrees() - ra()->Degrees() );
	int dSec = int( -3600.*HourAngle.Hours() );

	//dt0 is the first guess at the transit time.
	KStarsDateTime dt0 = dt.addSecs( dSec );

	//recompute object's position at UT0 and then find
	//transit time of this refined position
	SkyPoint sp = recomputeCoords( dt0, geo );
	const dms *ram = sp.ra0();

	HourAngle = dms ( LST.Degrees() - ram->Degrees() );
	dSec = int( -3600.*HourAngle.Hours() );

	return dt.addSecs( dSec ).time();
}